<PAGE>   1


                                                          Exhibit 12


                                                        [MEDUSA LOGO]


                                U.S. $45,000,000

                              AMENDED AND RESTATED
                           REVOLVING CREDIT AGREEMENT

                          Dated as of January 27, 1993
                         and amended and restated as of
                                December 15, 1995


                                      Among


                               MEDUSA CORPORATION

                                   as Borrower


                                       and

                             THE BANKS NAMED HEREIN

                                    as Banks

                                       and

                              SOCIETY NATIONAL BANK

                                    as Agent









<PAGE>   2





                                U.S. $45,000,000





                              AMENDED AND RESTATED
                           REVOLVING CREDIT AGREEMENT

                          Dated as of January 27, 1993
                         and amended and restated as of
                                December 15, 1995


                                      Among


                               MEDUSA CORPORATION

                                   as Borrower


                                       and

                             THE BANKS NAMED HEREIN

                                    as Banks

                                       and

                              SOCIETY NATIONAL BANK

                                    as Agent













<PAGE>   3



<TABLE>
<CAPTION>

                                                 TABLE OF CONTENTS

                                                                                                               Page

<S>                                                                                                            <C>
ARTICLE I
DEFINITIONS AND ACCOUNTING TERMS................................................................................  1
        SECTION 1.01.      Certain Defined Terms................................................................  1
        SECTION 1.02.      Computation of Time Periods.......................................................... 10
        SECTION 1.03.      Accounting Terms..................................................................... 10

ARTICLE II
AMOUNTS AND TERMS OF THE ADVANCES............................................................................... 11
        SECTION 2.01.      The Advances......................................................................... 11
        SECTION 2.02.      Making the Advances.................................................................. 11
        SECTION 2.03.      Commitment Fee....................................................................... 12
        SECTION 2.04.      Reduction of the Commitments......................................................... 12
        SECTION 2.05.      Repayment............................................................................ 12
        SECTION 2.06.      Interest............................................................................. 12
        SECTION 2.07.      Additional Interest on Eurodollar Rate Advances...................................... 13
        SECTION 2.08.      Interest Rate Determination and Protection........................................... 13
        SECTION 2.09.      Voluntary Conversion of Advances..................................................... 14
        SECTION 2.10.      Prepayments.......................................................................... 14
        SECTION 2.11.      Increased Costs...................................................................... 14
        SECTION 2.12.      Illegality........................................................................... 15
        SECTION 2.13.      Payments and Computations............................................................ 15
        SECTION 2.14.      Sharing of Payments, etc............................................................. 15

ARTICLE III
CONDITIONS OF LENDING........................................................................................... 16
        SECTION 3.01.      Conditions Precedent at Restatement Effective Date................................... 16
        SECTION 3.02.      Conditions Precedent to Each Borrowing............................................... 16

ARTICLE IV
REPRESENTATIONS AND WARRANTIES.................................................................................. 17
        SECTION 4.01.      Representations and Warranties of the Borrower....................................... 17

ARTICLE V
COVENANTS OF THE BORROWER....................................................................................... 20
        SECTION 5.01.      Financial Statements; Information.................................................... 20
        SECTION 5.02.      Inspection of Properties and Books................................................... 23
        SECTION 5.03.      Corporate Existence; Payment of Taxes; Maintenance of Properties;
                             Insurance; Compliance with Laws, etc............................................... 23
        SECTION 5.04.      Books and Accounting................................................................. 24
        SECTION 5.05.      Nature of Business................................................................... 24
        SECTION 5.06.      Transactions with Affiliates......................................................... 24
        SECTION 5.07.      Subsidiary Stock and Debt; Subsidiary Dividends...................................... 25
        SECTION 5.08.      Consolidation, Merger, Sale of Assets, etc........................................... 25
        SECTION 5.09.      Sale-Leaseback Transactions.......................................................... 26
        SECTION 5.10.      Maintenance of Consolidated Tangible Net Worth....................................... 26
        SECTION 5.11.      Current Debt......................................................................... 27
        SECTION 5.12.      Liens................................................................................ 27
</TABLE>

                                                         i

<PAGE>   4
<TABLE>
<S>                                                                                                            <C>
                                                                                                               Page
        SECTION 5.13.      Current Ratio........................................................................ 28
        SECTION 5.14.      Ratio of Consolidated Liabilities to Consolidated Tangible Net Worth................. 28
        SECTION 5.15.      Interest Coverage Ratio.............................................................. 28
        SECTION 5.16.      Certain Subsidiaries to Guarantee Advances........................................... 28
        SECTION 5.17.      Investments, Acquisitions, etc....................................................... 29

ARTICLE VI
EVENTS OF DEFAULT............................................................................................... 29
        SECTION 6.01.      Events of Default.................................................................... 29

ARTICLE VII
THE AGENT....................................................................................................... 31
        SECTION 7.01.      Authorization and Action............................................................. 31
        SECTION 7.02.      Agent's Reliance, etc................................................................ 31
        SECTION 7.03.      Society and Affiliates............................................................... 32
        SECTION 7.04.      Bank Credit Decision................................................................. 32
        SECTION 7.05.      Indemnification...................................................................... 32
        SECTION 7.06.      Successor Agent...................................................................... 32

ARTICLE VIII
MISCELLANEOUS................................................................................................... 33
        SECTION 8.01.      Amendments, etc...................................................................... 33
        SECTION 8.02.      Notices, etc......................................................................... 33
        SECTION 8.03.      No Waiver; Remedies.................................................................. 33
        SECTION 8.04.      Costs, Expenses and Taxes............................................................ 33
        SECTION 8.05.      Right of Set-off..................................................................... 34
        SECTION 8.06.      Binding Effect....................................................................... 34
        SECTION 8.07.      Assignments and Participations....................................................... 34
        SECTION 8.08.      Governing Law........................................................................ 36
        SECTION 8.09.      Execution in Counterparts............................................................ 36
        SECTION 8.10.      Indemnification...................................................................... 36
        SECTION 8.11.      No Margin Stock Collateral........................................................... 36
        SECTION 8.12.      Jury Trial Waiver.................................................................... 36





Schedule I   - List of Applicable Lending Offices
Schedule II  - Certain ERISA Disclosures
Schedule III - Outstanding Debt

Exhibit A   -  Form of Promissory Note
Exhibit B   -  Notice of Borrowing
Exhibit C   -  Form of Opinion of Counsel for the Borrower 
Exhibit D   -  Form of Assignment and Acceptance 
Exhibit E   -  Form of Guaranty by Subsidiary

</TABLE>

                                                        ii

<PAGE>   5







                              AMENDED AND RESTATED
                           REVOLVING CREDIT AGREEMENT

                          Dated as of January 27, 1993
                         and amended and restated as of
                                December 15, 1995


         MEDUSA CORPORATION, an Ohio corporation (the "BORROWER"), the banks
(the "BANKS") listed on the signature pages hereof, and SOCIETY NATIONAL BANK, a
national banking association ("SOCIETY"), as agent (the "AGENT") for the Banks
hereunder, hereby amend and restate in its entirety the Revolving Credit
Agreement, dated as of January 27, 1993, as amended by amendments dated as of
November 1, 1993, May 1, 1994 and December 23, 1994 (as so amended and in effect
prior to the Restatement Effective Date (herein defined), the "ORIGINAL
AGREEMENT"), and agree as follows:

                                    ARTICLE I

                        DEFINITIONS AND ACCOUNTING TERMS

         SECTION 1.01. CERTAIN DEFINED TERMS. As used in this Agreement, the
following terms shall have the following meanings (such meanings to be equally
applicable to both the singular and plural forms of the terms defined):

         "ADJUSTED BASE RATE" means, for any period, a fluctuating interest rate
per annum as shall be in effect from time to time which rate per annum shall at
all times be equal to the higher of:

                  (i) the rate of interest announced publicly by Society in
         Cleveland, Ohio, from time to time, as Society's base rate; or

                  (ii) 1-1/2% per annum above the Federal Funds Rate.

         "ADJUSTED BASE RATE ADVANCE" means an Advance which bears interest as
provided in section 2.06(a).

         "ADVANCE" means an advance by a Bank to the Borrower pursuant to
Article II, and refers to an Adjusted Base Rate Advance or a Eurodollar Rate
Advance (each of which shall be a "TYPE" of Advance).

         "AFFILIATE" means with respect to any designated Person, any other
Person (i) directly or indirectly controlling or controlled by or under direct
or indirect common control with such designated Person, (ii) which other Person
beneficially owns or holds 5% or more of the shares of any class of Voting Stock
of such designated Person, or (iii) 5% or more of any class of the Voting Stock
of which is beneficially owned or held by such designated Person. For purposes
of this definition, "CONTROL" (including, with correlative meanings, the terms
"CONTROLLED BY" and "UNDER COMMON CONTROL WITH"), as used with respect to any
Person, shall mean the possession, directly or indirectly, of the power to
direct or cause the direction of the management and policies of such Person,
whether through the ownership of Voting Stock or by contract or otherwise.

         "APPLICABLE LENDING OFFICE" means, with respect to each Bank, such
Bank's Domestic Lending Office in the case of an Adjusted Base Rate Advance, and
such Bank's Eurodollar Lending Office in the case of a Eurodollar Rate Advance.





<PAGE>   6



         "ATTRIBUTABLE DEBT" means in respect of any Sale-Leaseback Transaction,
as at any date of determination, the lesser of (i) the fair market value of the
assets the subject of such Sale-Leaseback Transaction or (ii) the present value
(discounted in accordance with GAAP at the rate of interest implicit in the
terms of the applicable lease) of the obligation of the lessee for net rental
payments during the remaining term of such Sale-Leaseback Transaction (including
any period for which such lease has been extended or may, at the option of the
lessor, be extended). As used in this definition, "net rental payments" under
any lease for any period means the sum of such rental and other payments
required to be paid in such period by the lessee thereunder, but excluding,
however, any amount required to be paid by such lessee (whether or not
designated as rent or additional rent) on account of maintenance and repairs,
insurance, taxes, assessments, water rates or similar charges required to be
paid by such lessee thereunder or any amounts required to be paid by such lessee
thereunder contingent upon the amount of sales, maintenance and repairs,
insurance, taxes, assessments, water rates or similar charges.

         "BOARD OF DIRECTORS" means the Board of Directors of the Borrower or a
duly authorized committee of directors or any other officer of the Borrower
pursuant to an express delegation of authority by the Board of Directors, in any
such case lawfully exercising the relevant powers of such Board.

         "BORROWING" means a borrowing consisting of Advances of the same Type
made on the same day by the Banks.

         "BUSINESS DAY" means a day of the year on which banks are not required
or authorized to close in Cleveland, Ohio and, if the applicable Business Day
relates to any Eurodollar Rate Advances, on which dealings are carried on in the
London interbank market.

         "BUSINESS OR CONDITION" means, with respect to any Person, the
business, operations, assets, properties, earnings, reasonably foreseeable
prospects or condition (financial or other) of such Person, PROVIDED that such
term, when used without reference to any particular Person, shall mean the
Business or Condition of the Borrower and its Subsidiaries, taken as a whole.

         "CAPITAL LEASE" means, as applied to any Person, any lease of any
property (whether real, personal or mixed) by such Person as lessee which would,
in accordance with GAAP, be required to be classified and accounted for as a
capital lease on the balance sheet of such Person, other than, in the case of
the Borrower or a Restricted Subsidiary, any such lease under which the Borrower
or a Wholly-owned Restricted Subsidiary is the lessor.

         "CAPITAL LEASE OBLIGATION" means with respect to any Capital Lease, the
amount of the obligation of the lessee thereunder which would, in accordance
with GAAP, appear on a balance sheet of such lessee (or the notes thereto) in
respect of such Capital Lease.

         "CASH EQUIVALENTS" means any of the following, to the extent owned by
any Person free and clear of all Liens and having a maturity of not greater than
90 days from the date of acquisition thereof; (a) readily marketable direct
obligations of the Government of the United States or any agency or
instrumentality thereof or obligations unconditionally guaranteed by the full
faith and credit of the Government of the United States, (b) insured
certificates of deposit of or time deposits with any commercial bank that is a
Bank or is a bank or trust company which is organized under the laws of the
United States or any State thereof, has combined capital and surplus of at least
$500 million, is a member of the Federal Reserve System and which issues (or the
parent of which issues) commercial paper rated as described in clause (c), or
(c) commercial paper in an aggregate amount of no more than $1,000,000 per
issuer outstanding at any time, issued by any corporation organized under the
laws of any State of the United States, rated at least "Prime-1" (or the then
equivalent grade) by Moody's Investors Services, Inc. or "A-1" (or the then
equivalent grade) by Standard & Poor's Corporation.

         "CHANGE IN CONTROL" means and includes any of the following:

                  (i) any Person or related group of Persons determined in
         accordance with section 13(d) of the Securities Exchange Act of 1934,
         in one or more transactions, together with its or their Affiliates or




                                        2

<PAGE>   7



         Associates, is or becomes the beneficial owner, directly or indirectly,
         through a purchase, merger or other acquisition transaction or
         otherwise, of a majority of the outstanding Voting Stock of the
         Borrower;

                  (ii) a majority of the Board of Directors of the Borrower (or
         similar governing body, in the event the Borrower is not a corporation)
         are not Continuing Directors; or

                  (iii) the shareholders of the Borrower adopt a plan of
         liquidation with respect to the Borrower or the Borrower sells,
         transfers, leases or otherwise disposes of, in one transaction or a
         series of related transactions, all or substantially all of its assets.

For purposes of this definition, (a) an "Affiliate" of, or a Person "affiliated"
with, any Person, means any Person directly or indirectly controlling or
controlled by, or under the direct or indirect common control with, such Person;
(b) an "Associate" of, or a Person "associated" with, any Person, means (i) any
trust or other estate in which such Person has a substantial beneficial interest
or as to which such Person serves as a trustee or in a similar fiduciary
capacity and (ii) any relative or spouse of such Person, or any relative of such
spouse, who has the same home as such Person; (c) the term "beneficial owner"
shall be determined in accordance with Rule 13d-3 and Rule 13d-5 of the
Commission under the Securities Exchange Act of 1934 as in effect on the date
hereof; and (d) "Continuing Director" means at any date a member of the Board of
Directors (or similar governing body, in the event the Borrower is not a
corporation) of the Borrower who (i) was a member of the Board of Directors of
the Borrower on the date hereof or (ii) was nominated for election or elected to
the Board of Directors (or similar governing body, in the event the Borrower is
not a corporation) of the Borrower with the affirmative vote of at least a
majority of the directors (or similar Persons) who were Continuing Directors at
the time of such nomination or election (which may be done by approval of the
proxy statement in which such member was named as a nominee for director (or
similar Person) of the Borrower).

         "CODE" means the Internal Revenue Code of 1986, as amended from time to
time.

         "COMMISSION" means the Securities and Exchange Commission and any other
similar or successor agency of the Federal government administering the
Securities Act.

         "COMMITMENT" has the meaning specified in section 2.01.

         "COMPANY GROUP MEMBER" means the Borrower, each Subsidiary of the
Borrower, and each of their respective predecessors and (i) each corporation
that is or was at any time a member of the same controlled group of corporations
(within the meaning of section 414(b) of the Code) as the Borrower or any
Subsidiary of the Borrower or any of their respective predecessors, (ii) each
trade or business, whether or not incorporated, that is or was at any time under
common control (within the meaning of section 414(c) of the Code) with the
Borrower or any Subsidiary of the Borrower or any of their respective
predecessors, and (iii) (solely with respect to any provision of the Code or
ERISA with respect to which a liability incurred by an affiliated service group
member (as defined below could attach to or result in a lien upon the assets of
the Borrower or any Subsidiary) each trade or business, whether or not
incorporated, that is or was at any time a member of the same affiliated service
group (within the meaning of section 414(m) and (o) of the Code) as the Borrower
or any Subsidiary of the Borrower or any of their respective predecessors;
PROVIDED, HOWEVER, that the term "Company Group Member" shall not include any
corporation or trade or business for any period during which the termination of
or withdrawal from any employee pension benefit plan (as defined in section 3(2)
of ERISA) by such corporation or trade or business could not subject the
Borrower or any Subsidiary to any liability under the Code or ERISA.

         "CONSOLIDATED CURRENT ASSETS" means as at any date of determination all
assets of the Borrower and its Restricted Subsidiaries which would, in
accordance with GAAP on a consolidated basis, after eliminating all
inter-company items, be classified as current assets of a company conducting a
business similar to that of the Borrower, after deducting adequate reserves in
each case in which a reserve is proper in accordance with GAAP.





                                        3

<PAGE>   8



         "CONSOLIDATED CURRENT LIABILITIES" means as at any date of
determination all Consolidated Liabilities of the Borrower and its Restricted
Subsidiaries which would, in accordance with GAAP on a consolidated basis, after
eliminating all inter-company items, be classified as current liabilities in
accordance with GAAP.

         "CONSOLIDATED INCOME TAX EXPENSE" means for any period, the aggregate
of all expenses for taxes based on net income and all franchise taxes of the
Borrower and its Restricted Subsidiaries, determined in accordance with GAAP on
a consolidated basis, after eliminating all inter-company items.

         "CONSOLIDATED INTEREST EXPENSE" means for any period the aggregate
amount of interest in respect of Debt of the Borrower and its Restricted
Subsidiaries, determined in accordance with GAAP on a consolidated basis, after
eliminating all inter-company items, including, without limitation, the
amortization of original issue discount on any such Debt and the interest
portion of any deferred payment obligation, calculated in accordance with the
effective interest method of accounting, and the net costs associated with
interest rate protection agreements and all but the principal component of
Rental Obligations, paid, accrued or scheduled to be paid or accrued during such
period. For purposes of this definition, interest on the principal component of
Rental Obligations shall be deemed to accrue at an interest rate reasonably
determined in accordance with GAAP.

         "CONSOLIDATED FUNDS FROM OPERATIONS" means for any period, Consolidated
Net Income for such period PLUS, to the extent deducted in determining the
amount thereof, (i) amortization and depreciation PLUS (ii) other non-cash
charges to income of the Borrower and its Restricted Subsidiaries, PROVIDED,
HOWEVER, that Consolidated Funds from Operations shall not include the income
from any Unrestricted Subsidiary except to the extent such income has actually
been received by the Borrower or any Restricted Subsidiary in the form of cash.

         "CONSOLIDATED LIABILITIES" means as at any date of determination all
obligations of the Borrower and its Restricted Subsidiaries which would, in
accordance with GAAP on a consolidated basis, after eliminating all
inter-company items, be included in determining total liabilities as shown on
the liabilities side of a consolidated balance sheet of the Borrower and its
Restricted Subsidiaries at such date and, in any event, including all Debt of
the Borrower and its Restricted Subsidiaries on a consolidated basis after
eliminating all inter-company items.

         "CONSOLIDATED NET INCOME" means for any period, the net income (or
deficit) of the Borrower and its Restricted Subsidiaries for such period (taken
as a cumulative whole) after deducting, without duplication, all interest
expense, rentals, operating expenses, provisions for all taxes and reserves
(including reserves for deferred income taxes) and all other proper deductions,
all determined in accordance with GAAP on a consolidated basis, after
eliminating all inter-company items; PROVIDED, HOWEVER, that there shall be
excluded from Consolidated Net Income (i) the income (or deficit) of any other
Person accrued prior to the date it becomes a Subsidiary of the Borrower or is
merged into or consolidated with the Borrower or a Subsidiary of the Borrower,
(ii) the income (or deficit) of any Person (other than a Restricted Subsidiary
of the Borrower) in which the Borrower or any of its Restricted Subsidiaries has
an ownership interest, except to the extent that any such income has been
actually received by the Borrower or such Restricted Subsidiary in the form of
cash dividends or similar distributions, and (iii) any item properly classified
as extraordinary in accordance with GAAP.

         "CONSOLIDATED TANGIBLE NET WORTH" means as at any date of
determination, the amount of "Total Shareholders' Equity" of the Borrower as
shown on the most recent balance sheet of the Borrower prepared and delivered to
the Banks pursuant to section 5.01, LESS the net book value of all items of the
following character acquired after December 31, 1992, to the extent, if any,
they are included in consolidated assets of the Borrower and its Subsidiaries or
deducted from consolidated liabilities of the Borrower and its Subsidiaries:
franchises, licenses, permits, patents, patent applications, copyrights,
trademarks, trade names, good will, experimental or organizational expense,
unamortized debt discount and expense, deferred charges, and treasury stock, and
less any amounts of deposits, trusts arrangements or similar arrangements made
by the Borrower and its Restricted Subsidiaries in the amount necessary to pay,
satisfy or redeem any obligation of the Borrower and any Restricted Subsidiary
which would, in accordance with GAAP, be classified on its balance sheet as
debt.





                                        4

<PAGE>   9



         "CONSOLIDATED TOTAL DEBT" means as at any date of determination, the
aggregate principal amount of all Debt of the Borrower and its Restricted
Subsidiaries outstanding on such date, determined in accordance with GAAP on a
consolidated basis after eliminating all inter-company items.

         "CONVERTIBLE SUBORDINATED NOTES" means up to $57,500,000 of the
Borrower's Convertible Subordinated Notes due 2003, issued in an underwritten
public offering, as contemplated by the Registration Statement on Form S-3 filed
by the Borrower with the Securities and Exchange Commission on October 22, 1993,
including any amendments thereto so filed on or before the date such
Registration Statement becomes effective.

         "CURRENT DEBT" means as at any date of determination, all Debt maturing
or payable on demand or within one year from the date of the creation thereof
including any Debt that is by its terms or by the terms of any instrument or
agreement relating thereto directly or indirectly renewable or extendible, at
the option of the debtor, to a date beyond such year, including any outstanding
amounts of any revolving credit facility, but excluding any fixed or contingent
payments maturing or required to be made not more than one year after such date
in respect of the principal and premium, if any, on any Funded Debt. Any Debt
that is extended or renewed shall be deemed to have been created at the date of
such extension or renewal.

         "CONVERT", "CONVERSION" and "CONVERTED" each refers to a conversion of
Advances of one Type into Advances of another Type pursuant to section 2.08 or
2.09.

         "DEBT" means, with respect to any Person (i) all obligations (whether
or not represented by bonds, debentures, notes or other securities) of such
Person for borrowed money (and any notes payable and drafts accepted
representing extensions of credit whether or not representing obligations for
borrowed money), (ii) any obligation of such Person for all or any part of the
purchase price of property or other assets or for the cost of property or other
assets constructed or of improvements, other than accounts payable included in
current liabilities and incurred in respect of property purchased in the
ordinary course of business and not required to be classified on its balance
sheet, in accordance with GAAP, as debt, (iii) any obligation secured by any
Lien on or payable out of the proceeds of production from property owned or held
by such Person whether or not such Person has assumed or become liable for the
payment of such obligation, (iv) any Capital Lease Obligation of such Person,
and (v) any Guaranty by such Person of or with respect to Debt of another
Person, except Debt shall not include any Debt which is extinguished in
accordance with GAAP due to deposits, trust arrangements or similar arrangements
made by such Person in the amount necessary to pay, satisfy or redeem such Debt.

         "DEFAULT" means any condition or event which, with notice or lapse of
time or both, would become an Event of Default.

         "DOMESTIC LENDING OFFICE" means, with respect to any Bank, the office
of such Bank specified as its "Domestic Lending Office" opposite its name on
Schedule I hereto, or such other office of such Bank as such Bank may from time
to time specify to the Borrower and the Agent.

         "ELIGIBLE ASSIGNEE": shall mean (a) a commercial bank organized under
the laws of the United States, or any State thereof, which is a Subsidiary of
any Bank or a Subsidiary of any parent corporation of any Bank; (b) any other
commercial bank organized under the laws of the United States, or any State
thereof, and having total assets in excess of $3,000,000,000 and a combined
capital and surplus of at least $150,000,000; (c) a savings and loan association
or savings bank organized under the laws of the United States, or any State
thereof, and having total assets in excess of $3,000,000,000 and a combined
capital and surplus of at least $150,000,000; (d) a finance company or other
financial institution (whether a corporation, partnership, trust or other
entity) that is engaged in making, purchasing or otherwise investing in
commercial loans in the ordinary course of its business and having total assets
in excess of $500,000,000; and (e) any other person (other than an Affiliate of
the Borrower) approved by the Agent and, if no Event of Default shall have
occurred and be continuing, the Borrower (whose approval will not be
unreasonably withheld or delayed).

         "ENVIRONMENTAL LAW" means any past, present or future Federal, state,
local or foreign statutory or common law, or any regulation, code, plan, order,
decree, judgment, permit, grant, franchise, concession,




                                        5

<PAGE>   10



restriction, agreement or injunction issued, entered, promulgated or approved
thereunder, relating to (i) the environment, human health or safety, including,
without limitation, any law relating to emissions, discharges, releases or
threatened releases of Hazardous Substances into the environment (including,
without limitation, air, surface water, groundwater or land), or (ii) the
manufacture, generation, refining, processing, distribution, use, sale,
treatment, recycling, receipt, storage, disposal, transport, arranging for
transport, or handling of Hazardous Substances.

         "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended from time to time.

         "EUROCURRENCY LIABILITIES" has the meaning assigned to that term in
Regulation D of the Board of Governors of the Federal Reserve System, as in
effect from time to time.

         "EURODOLLAR LENDING OFFICE" means, with respect to any Bank, the office
of such Bank specified as its "Eurodollar Lending Office" opposite its name on
Schedule I hereto (or, if no such office is specified, its Domestic Lending
Office), or such other office of such Bank as such Bank may from time to time
specify to the Borrower and the Agent.

         "EURODOLLAR RATE" means, for any Interest Period for each Eurodollar
Rate Advance comprising part of the same Borrowing, an interest rate per annum
equal to the average (rounded upward to the nearest whole multiple of 1/16 of 1%
per annum, if such average is not such a multiple) of the rate per annum at
which deposits in U.S. dollars are offered to the Agent in or through the London
interbank market at or about 11:00 A.M. (London time) two Business Days before
the first day of such Interest Period in an amount substantially equal to the
Eurodollar Rate Advances comprising part of such Borrowing and for a period
equal to such Interest Period. The Eurodollar Rate for the Interest Period for
each Eurodollar Rate Advance comprising part of the same Borrowing shall be
determined by the Agent on the basis of applicable rates furnished to and
received by the Agent two Business Days before the first day of such Interest
Period, SUBJECT, HOWEVER, to the provisions of section 2.08.

         "EURODOLLAR RATE ADVANCE" means an Advance which bears interest as
provided in section 2.06(b).

         "EURODOLLAR RATE RESERVE PERCENTAGE" of any Bank for the Interest
Period for any Eurodollar Rate Advance means the reserve percentage applicable
during such Interest Period (or if more than one such percentage shall be so
applicable, the daily average of such percentages for those days in such
Interest Period during which any such percentage shall be so applicable) under
regulations issued from time to time by the Board of Governors of the Federal
Reserve System (or any successor) for determining the maximum reserve
requirement (including, without limitation, any emergency, supplemental or other
marginal reserve requirement) for such Bank with respect to liabilities or
assets consisting of or including Eurocurrency Liabilities having a term equal
to such Interest Period.

         "EVENTS OF DEFAULT" has the meaning specified in section 6.01.

         "EXCHANGE ACT" means the Securities Exchange Act of 1934, or any
similar Federal statute, and the rules and regulations of the Commission
thereunder, all as the same may be in effect at the time.

         "FEDERAL FUNDS RATE" means, for any period, a fluctuating interest rate
per annum equal for each day during such period to the weighted average of the
rates on overnight Federal funds transactions with members of the Federal
Reserve System only, arranged by Federal funds brokers. The Federal Funds Rate
shall be determined by the Agent on the basis of reports by Federal funds
brokers to, and published daily by, the Federal Reserve Bank of New York in the
Composite Closing Quotations for U.S. Government Securities. If such publication
is unavailable or the Federal Funds Rate is not set forth therein, the Federal
Funds Rate shall be determined on the basis of any other source reasonably
selected by the Agent. The Federal Funds Rate applicable each day shall be the
Federal Funds Rate reported as applicable to Federal Funds transactions on that
date. In the case of Saturday, Sunday or legal holiday, the Federal Funds Rate
shall be the rate applicable to Federal funds transactions on the immediately
preceding day for which the Federal Funds Rate is reported.





                                        6

<PAGE>   11



         "FUNDED DEBT" means for any Person, all Debt of such Person which in
accordance with GAAP would be classified on a balance sheet of such Person as of
such date as long-term debt, and including in any event all Debt of such Person,
whether secured or unsecured, having a final maturity (or which, pursuant to its
terms, is renewable or extendible at the option of such Person for a period
ending) more than one year after the date of the creation thereof (including any
portion thereof which is on such date included in current liabilities of such
Person), but excluding Current Debt of such Person.

         "GAAP" means generally accepted accounting principles as set forth in
the opinions of the Accounting Principles Board of the American Institute of
Certified Public Accountants and in statements by the Financial Accounting
Standards Board.

         "GOVERNMENTAL BODY" means any Federal, state, municipal or other
governmental department, commission, board, bureau, agency or instrumentality,
domestic or foreign.

         "GUARANTY" means as applied to any Person, any direct or indirect
liability, contingent or otherwise, of such Person with respect to any
indebtedness, lease, dividend or other obligation directly or indirectly
guaranteed, endorsed (otherwise than for collection or deposit in the ordinary
course of business) or discounted or sold with recourse by such Person, or in
respect of which such Person is otherwise directly or indirectly liable,
including, without limitation, any such obligation in effect guaranteed by such
Person by reason of the issuance of a letter of credit, surety or performance
bond, or through any agreement (contingent or otherwise) to purchase, repurchase
or otherwise acquire such obligation or any security therefor, or to provide
funds for the payment or discharge of such obligation (whether in the form of
loans, advances, stock purchases, capital contributions or otherwise), or to
maintain the solvency or any balance sheet or other financial condition of the
obligor of such obligation, or to make payment for any products, materials or
supplies or for any transportation or services regardless of the non-delivery or
non-furnishing thereof, in any such case if the purpose or intent of such
agreement is to provide assurance that such obligation will be paid or
discharged, or that any agreements relating thereto will be complied with, or
that the holders of such obligation will be protected against loss in respect
thereof. The amount of any Guaranty shall be equal to the amount of the
obligation guaranteed.

         "HAZARDOUS SUBSTANCES" means collectively, contaminants; pollutants;
toxic or hazardous chemicals, substances, materials, wastes and constituents;
petroleum products; polychlorinated biphenyls; medical wastes; infectious
wastes; asbestos; paint containing lead; and urea formaldehyde.

         "INTEREST COVERAGE RATIO" means at any date of determination the ratio
of (i) Consolidated Net Income for the twelve months most recently ended, PLUS
Consolidated Interest Expense and Consolidated Income Tax Expense for such
period, to (ii) Consolidated Interest Expense for such period.

         "INTEREST PERIOD" means, for each Eurodollar Rate Advance comprising
part of the same Borrowing, the period commencing on the date of such Advance or
the date of the Conversion of any Advance into such an Advance and ending on the
last day of the period selected by the Borrower pursuant to the provisions below
and, thereafter, each subsequent period commencing on the last day of the
immediately preceding Interest Period and ending on the last day of the period
selected by the Borrower pursuant to the provisions below. The duration of each
such Interest Period shall be 1, 2, 3 or 6 months in the case of a Eurodollar
Rate Advance, in each case as the Borrower may, upon notice received by the
Agent not later than 11:00 A.M. (Cleveland, Ohio time) on the third Business Day
prior to the first day of such Interest Period, select; PROVIDED, HOWEVER, that:

                  (i) the duration of any Interest Period which commences before
         the Termination Date and otherwise ends after the Termination Date
         shall end on the Termination Date;

                  (ii) Interest Periods commencing on the same date for Advances
         comprising part of the same Borrowing shall be of the same duration;
         and

                  (iii) whenever the last day of any Interest Period would
         otherwise occur on a day other than a Business Day, the last day of
         such Interest Period shall be extended to occur on the next succeeding




                                        7

<PAGE>   12



         Business Day, PROVIDED, in the case of any Interest Period for a
         Eurodollar Rate Advance, that if such extension would cause the last
         day of such Interest Period to occur in the next following calendar
         month, the last day of such Interest Period shall occur on the next
         preceding Business Day.

         "LIEN" means as to any Person, any mortgage, lien, pledge, adverse
claim, charge, security interest or other encumbrance in or on, or any interest
or title of any vendor, lessor, lender or other secured party to or of such
Person under any conditional sale or other title retention agreement or Capital
Lease with respect to, any property or asset of such Person, or the signing or
filing of a financing statement which names such Person as debtor, or the
signing of any security agreement authorizing any other party as the secured
party thereunder to file any financing statement which names such Person as
debtor.

         "MAJORITY BANKS" means at any time Banks holding at least 75% of the
then aggregate unpaid principal amount of the Notes held by Banks, or, if no
such principal amount is then outstanding, Banks having at least 75% of the
Commitments.

         "MATERIAL ADVERSE CHANGE"; "MATERIAL ADVERSE EFFECT"; "MATERIALLY
ADVERSE" means, as applied in, on or to any Person, as appropriate, a material
adverse change in such Person's Business or Condition, a material adverse effect
on such Person's Business or Condition and an event which is materially adverse
to such Person's Business or Condition; PROVIDED, that any such term, when used
without reference to any particular Person, shall mean such change in or effect
on or to the Borrower and its Subsidiaries, taken as a whole.

         "MULTIEMPLOYER PLAN" means a Plan defined as such in section 4001(a)(3)
of ERISA to which any Company Group Member is making or incurring an obligation
to make, or has made or incurred an obligation to make contributions.

         "MULTIPLE EMPLOYER PLAN" means a Plan to which any Company Group
member, and at least one employer other than any Company Group Member, is making
or accruing an obligation to make contributions or, in the event that any such
plan has been terminated, has made or accrued an obligation to make
contributions during any of the five plan years preceding the date of
termination of such plan.

         "NOTE" means a promissory note of the Borrower payable to the order of
any Bank, in substantially the form of Exhibit A hereto, evidencing the
aggregate indebtedness of the Borrower to such Bank resulting from the Advances
made by such Bank.

         "OFFICER'S CERTIFICATE" means a certificate executed on behalf of the
Borrower by the Chairman of the Board of Directors (if an officer) or its
President or one of its Vice Presidents or its Chief Financial Officer or its
Treasurer.

         "ORDER" means any order, writ, injunction, decree, judgment, award,
determination, direction or demand.

         "ORIGINAL AGREEMENT" has the meaning specified in the introductory 
paragraph of this Agreement.

         "NOTICE OF BORROWING" has the meaning specified in section 2.02.

         "PBGC" means the Pension Benefit Guaranty Corporation established
pursuant to Subtitle A of Title IV of ERISA and any successor thereof.

         "PERSON" means an individual, partnership, corporation (including a
business trust), joint stock company, trust, unincorporated association, joint
venture or other entity, or a government or any political subdivision or agency
thereof.

         "PLAN" means any employee pension benefit plan (as defined in section
3(2)of ERISA) maintained at any time, or contributed to, by any Company Group
Member.





                                        8

<PAGE>   13



         "PREFERRED STOCK" means as applied to any corporation, shares of such
corporation which are entitled to preference or priority over any other shares
of such corporation in respect of either the payment of dividends or the
distribution of assets upon liquidation.

         "PRIORITY DEBT" means as at any date of determination after the date
hereof, the sum (without duplication) of (A) the aggregate principal amount
outstanding of all Debt of Restricted Subsidiaries (other than Debt of any
Restricted Subsidiary to the Borrower or to another Restricted Subsidiary)
created or otherwise incurred after the date hereof, PLUS (B) the aggregate
principal amount outstanding of all Debt of the Borrower and Restricted
Subsidiaries (other than Debt of any Restricted Subsidiary to the Borrower or to
another Restricted Subsidiary) created or otherwise incurred after the date
hereof and secured by a Lien not otherwise permitted under clauses (a) through
(i) of section 5.12, PLUS (C) the aggregate amount of Attributable Debt of the
Borrower and Restricted Subsidiaries in effect on such date.

         "RENTAL OBLIGATIONS" means for any period, the total amount (whether or
not designated as rentals or additional or supplemental rentals) payable by the
Borrower or any Restricted Subsidiary under any Capital Lease during such period
(in each case exclusive of amounts so payable on account of maintenance,
repairs, insurance, taxes, assessments and other similar charges); if and to the
extent that the amount of any Rental Obligation during any future period is not
definitely determinable under the Capital Lease in question, the amount of such
Rental Obligation shall be estimated in such reasonable manner as the Board of
Directors in good faith may determine.

         "REPORTABLE EVENT" means any of the events set forth in section 4043(b)
of ERISA, or the regulations thereunder, other than those events as to which the
thirty-day notice requirement of such section or such regulations is waived
under subsection .13, .14, .18, .19 or .20 of PBGC Reg. ss. 2615.

         "RESTATEMENT EFFECTIVE DATE" means the date this Agreement becomes
effective as provided in section 8.06.

         "RESTRICTED SUBSIDIARY" means any Subsidiary which is organized under
the laws of, and which at the time in question conducts substantially all of its
business and maintains substantially all of its property and assets within, the
United States of America, or any state thereof, Canada, or any province thereof,
or Mexico, and at least 80% of the Voting Stock of which is at the time owned by
the Borrower or by one or more Wholly-owned Restricted Subsidiaries or by the
Borrower and one or more Wholly-owned Restricted Subsidiaries.

         "SALE-LEASEBACK TRANSACTION" means any arrangement with any Person
providing for the leasing by the Borrower or any Restricted Subsidiary, as
lessee, of any property that, or of any property similar to and used for
substantially the same purposes as any other property that, has been or is to be
sold or otherwise transferred by the Borrower or any Restricted Subsidiary to
such Person (or an Affiliate of such Person) with the intention of entering into
such a lease.

         "SECURITIES ACT" means the Securities Act of 1933, or any similar
Federal statute, and the rules and regulations of the Commission thereunder, all
as the same shall be in effect at the time.

         "SUBSIDIARY" means any Person more than 50% of the Voting Stock of
which is at the time owned by the Borrower or by one or more Wholly-owned
Restricted Subsidiaries or by the Borrower and one or more Wholly- owned
Restricted Subsidiaries.

         "TERMINATION DATE" means December 31, 2000 or the earlier date of
termination in whole of the Commitments pursuant to section 2.04 or 6.01.

         "TERMINATION EVENT" means (i) with respect to any Plan other than a
Multiemployer Plan, the occurrence or expected occurrence of a Reportable Event
or an event described in section 4062(e) of ERISA, (ii) the withdrawal of any
Company Group Member from a Multiple Employer Plan during a plan year in which
it was a "substantial employer," as such term is defined in section 4001(a)(2)
of ERISA, or the incurrence of liability



                                        9

<PAGE>   14


by any Company Group Member under section 4064 of ERISA upon the termination of
a Multiple Employer Plan, (iii) the distribution of a notice of intent to
terminate a Plan or Multiemployer Plan pursuant to section 4041(a)(2) or 4041A
of ERISA or the treatment of a Plan amendment as a termination under section
4041 or 4041A of ERISA, (iv) the institution of proceedings to terminate a Plan
or Multiemployer Plan by the PBGC under section 4042 of ERISA, (v) any other
event or condition which would reasonably be expected to result in the
termination by the PBGC of, or the appointment by the PBGC of a trustee to
administer, any Plan or Multiemployer Plan under section 4042 of ERISA, or (vi)
the complete or partial withdrawal of any Company Group Member from a
Multiemployer Plan.

         "TOTAL CAPITALIZATION" means at any time, the sum of (i) Consolidated
Tangible Net Worth PLUS (ii) Consolidated Total Debt PLUS (iii) the aggregate
amount (without duplication) of deferred income taxes of the Borrower and its
Restricted Subsidiaries at such time.

         "UNFUNDED CURRENT LIABILITY" means, with respect to any Plan, the
amount, if any, by which the present value of the accrued benefits under the
Plan (based on those assumptions used to fund such Plan) as of the close of its
most recent plan year exceeds the then current value of the assets of such Plan
allocable to such benefits.

         "UNRESTRICTED SUBSIDIARY" means any Subsidiary other than a Restricted
Subsidiary.

         "VOTING STOCK" means with respect to (i) any corporation, capital stock
of such corporation the holders of which are ordinarily, in the absence of
contingencies, entitled to elect a majority of the corporate directors (or
persons performing similar functions), and (ii) any other Person (other than a
corporation) any shares, interests, participations or other equivalents (however
designated) representing beneficial interests in such Person or in the capital
or profits of such Person.

         "WHOLLY-OWNED RESTRICTED SUBSIDIARY" means any Restricted Subsidiary,
all of the equity securities (except directors' qualifying shares) of which are
owned by the Borrower or another Wholly-owned Restricted Subsidiary.

         SECTION 1.02. COMPUTATION OF TIME PERIODS. In this Agreement in the
computation of periods of time from a specified date to a later specified date,
the word "from" means "from and including" and the words "to" and "until" each
means "to but excluding".

         SECTION 1.03. ACCOUNTING TERMS. All accounting terms not specifically
defined herein shall be construed in accordance with generally accepted
accounting principles consistent with those applied in the preparation of the
financial statements referred to in section 4.01(d); PROVIDED, HOWEVER, that if
any change in generally accepted accounting principles from those applied in the
preparation of the financial statements referred to in this Agreement (i) is
occasioned by the promulgation of rules, regulations, pronouncements and
opinions by or required by the Financial Accounting Standards Board or the
American Institute of Certified Public Accountants (or successors thereto or
agencies with similar functions), the initial announcement of which change is
made after the date of this Agreement, and (ii) results in a change in the
method of calculation of financial covenants, standards or terms found in this
Agreement, the parties hereto agree to enter into good faith negotiations in
order to amend such provisions so as to reflect such changes with the desired
result that the criteria for evaluating the Borrower's financial condition shall
be the same after such changes as if such changes had not been made; and
PROVIDED, FURTHER, that until such time as the parties hereto agree upon such
amendments, such financial covenants, standards and terms shall be construed and
calculated as though such change had not taken place. When used herein, the term
"financial statement" shall include the notes and schedules thereto.



                                       10
<PAGE>   15


                                   ARTICLE II

                        AMOUNTS AND TERMS OF THE ADVANCES

         SECTION 2.01. THE ADVANCES. Each Bank severally agrees, on the terms
and conditions hereinafter set forth, to make Advances to the Borrower from time
to time on any Business Day during the period from the date hereof until the
Termination Date in an aggregate amount not to exceed at any time outstanding
the amount set opposite such Bank's name on the signature pages hereof, as such
amount may be reduced pursuant to section 2.04 (such Bank's "COMMITMENT"). Each
Borrowing shall be in an aggregate amount not less than $3,000,000 or an
integral multiple of $1,000,000 in excess thereof and shall consist of Advances
of the same Type made on the same day by the Banks ratably according to their
respective Commitments. Within the limits of each Bank's Commitment, the
Borrower may borrow, prepay pursuant to section 2.10 and reborrow as provided in
this section 2.01.

         SECTION 2.02. MAKING THE ADVANCES. (a) Each Borrowing shall be made on
notice, given not later than 11:00 A.M. (Cleveland, Ohio time) on the third
Business Day prior to the date of the proposed Borrowing in the case of
Eurodollar Rate Advances and not later than 11:00 A.M. (Cleveland, Ohio time) on
the Business Day prior to the date of the proposed Borrowing in the case of
Adjusted Base Rate Advances, by the Borrower to the Agent, which shall give to
each Bank prompt notice thereof by telecopier, telex or cable. Each such notice
of a Borrowing (a "NOTICE OF BORROWING") shall be by telecopier, telex or cable,
confirmed immediately in writing, in substantially the form of Exhibit B hereto,
specifying therein the requested (i) date of such Borrowing, (ii) Type of
Advances comprising such Borrowing, (iii) aggregate amount of such Borrowing,
and (iv) in the case of a Borrowing comprised of Eurodollar Rate Advances, the
initial Interest Period for such Advances. Each Bank shall, before 11:00 A.M.
(Cleveland, Ohio time) on the date of such Borrowing, make available for the
account of its Applicable Lending Office to the Agent at its address referred to
in section 8.02, in same day funds, such Bank's ratable portion of such
Borrowing. After the Agent's receipt of such funds and upon fulfillment of the
applicable conditions set forth in Article III, the Agent will make such funds
available to the Borrower at the Agent's aforesaid address.

         (b) Each Notice of Borrowing shall be irrevocable and binding on the
Borrower. In the case of any Borrowing which the related Notice of Borrowing
specifies is to be comprised of Eurodollar Rate Advances, the Borrower shall
indemnify each Bank against any loss, cost or expense incurred by such Bank as a
result of any failure to fulfill on or before the date specified in such Notice
of Borrowing for such Borrowing the applicable conditions set forth in Article
III, including, without limitation, any loss (including loss of anticipated
profits), cost or expense incurred by reason of the liquidation or reemployment
of deposits or other funds acquired by such Bank to fund the Advance to be made
by such Bank as part of such Borrowing when such Advance, as a result of such
failure, is not made on such date.

         (c) Unless the Agent shall have received notice from a Bank prior to
the date of any Borrowing that such Bank will not make available to the Agent
such Bank's ratable portion of such Borrowing, the Agent may assume that such
Bank has made such portion available to the Agent on the date of such Borrowing
in accordance with subsection (a) of this section 2.02 and the Agent may, in
reliance upon such assumption, make available to the Borrower on such date a
corresponding amount. If and to the extent that such Bank shall not have so made
such ratable portion available to the Agent, such Bank and the Borrower
severally agree to repay to the Agent forthwith on demand such corresponding
amount together with interest thereon, for each day from the date such amount is
made available to the Borrower until the date such amount is repaid to the
Agent, at (i) in the case of the Borrower, the interest rate applicable at the
time to Advances comprising such Borrowing and (ii) in the case of such Bank,
the Federal Funds Rate. If such Bank shall repay to the Agent such corresponding
amount, such amount so repaid shall constitute such Bank's Advance as part of
such Borrowing for purposes of this Agreement.

         (d) The failure of any Bank to make the Advance to be made by it as
part of any Borrowing shall not relieve any other Bank of its obligation, if
any, hereunder to make its Advance on the date of such 

                                       11
<PAGE>   16

Borrowing, but no Bank shall be responsible for the failure of any other Bank to
make the Advance to be made by such other Bank on the date of any Borrowing.

         SECTION 2.03. COMMITMENT FEE. The Borrower agrees to pay to the Agent
for the account of each Bank a commitment fee on the average daily unused
portion of such Bank's Commitment from the Restatement Effective Date until the
Termination Date at the rate per annum determined in accordance with the Pricing
Grid contained in section 2.06, based on the ratio of the Borrower's
Consolidated Liabilities to Consolidated Tangible Net Worth as of the end of the
Borrower's fiscal quarter ended most recently prior to such Interest Period as
to which the Borrower shall have delivered to the Agent the financial statements
for such quarter (or the fiscal year ended with such fiscal quarter) referred to
in clause (a) or (b) of section 5.01, together with an Officer's Certificate
setting forth in reasonable detail the amounts of Consolidated Liabilities and
Consolidated Tangible Net Worth and the computation of such ratio, with changes
in such rate per annum being effective on the first of the month following such
delivery to the Agent, payable on the last day of each March, June, September
and December during the term of such Bank's Commitment, commencing on the first
such date after the Restatement Effective Date, and on the Termination Date. If
as of the Restatement Effective Date any commitment fees remain payable under
the Original Agreement for the period ending on the Restatement Effective Date,
the Borrower will pay to the Agent for the account of the Banks party to the
Original Agreement the amount of such commitment fees on the first date a
commitment fee is payable hereunder.

         SECTION 2.04. REDUCTION OF THE COMMITMENTS. The Borrower shall have the
right, upon at least five Business Days' notice to the Agent, to terminate in
whole or reduce ratably in part the unused portions of the respective
Commitments of the Banks, PROVIDED that each partial reduction shall be in the
aggregate amount of $3,000,000 or an integral multiple thereof.

         SECTION 2.05.     REPAYMENT.  The Borrower shall repay the unpaid 
principal amount of each Advance made by each Bank in accordance with the Note 
to the order of such Bank.

         SECTION 2.06. INTEREST. The Borrower shall pay interest on the unpaid
principal amount of each Advance made by each Bank from the date of such Advance
until such principal amount shall be paid in full, at the following rates per
annum:

                  (a) ADJUSTED BASE RATE ADVANCES. During such periods as such
         Advance is an Adjusted Base Rate Advance, a rate per annum equal at all
         times to the Adjusted Base Rate in effect from time to time, payable
         quarterly on the last day of each March, June, September, and December
         during such periods and on the date such Adjusted Base Rate Advance
         shall be Converted or paid in full; PROVIDED that any amount of
         principal which is not paid when due (whether at stated maturity, by
         acceleration or otherwise) shall bear interest, from the date on which
         such amount is due until such amount is paid in full, payable on
         demand, at a rate per annum equal at all times to 1% per annum above
         the Adjusted Base Rate in effect from time to time.

                  (b) EURODOLLAR RATE ADVANCES. During such periods as such
         Advance is a Eurodollar Rate Advance, a rate per annum equal at all
         times during each Interest Period for such Advance to the sum of (i)
         the Eurodollar Rate for such Interest Period for such Advance PLUS (ii)
         the Applicable Increment (as defined below) for such Interest Period,
         payable on the last day of such Interest Period and, if such Interest
         Period has a duration of more than three months, on each day which
         occurs during such Interest Period every three months from the first
         day of such Interest Period; PROVIDED that any amount of principal
         which is not paid when due (whether at stated maturity, by acceleration
         or otherwise) shall bear interest, from the date on which such amount
         is due until such amount is paid in full, payable on demand, at a rate
         per annum equal at all times to the greater of (x) 1% per annum above
         the Adjusted Base Rate in effect from time to time and (y) 2% per annum
         above the rate per annum required to be paid on such Advance
         immediately prior to the date on which such amount became due.

The "APPLICABLE INCREMENT" for any Interest Period commencing after the
Restatement Effective Date shall be equal to percentage rate per annum shown in
the Pricing Grid below in the column entitled Applicable




                                       12

<PAGE>   17

Increment corresponding to the ratio of the Borrower's Consolidated Liabilities
to Consolidated Tangible Net Worth as of the end of the Borrower's fiscal
quarter ended most recently prior to such Interest Period as to which the
Borrower shall have delivered to the Agent the financial statements for such
quarter (or the fiscal year ended with such fiscal quarter) referred to in
clause (a) or (b) of section 5.01, together with an Officer's Certificate
setting forth in reasonable detail the amounts of Consolidated Liabilities and
Consolidated Tangible Net Worth and the computation of such ratio.

                                  PRICING GRID

<TABLE>
<CAPTION>

RATIO OF CONSOLIDATED LIABILITIES
TO CONSOLIDATED TANGIBLE NET
WORTH                                  Applicable Increment  Commitment Fee Rate
<S>                                            <C>                   <C> 
Equal to or less than 1.50 to 1.00             .35%                  .20%
Equal to or less than 2.00 to 1.00             .45%                  .225%
Equal to or less than 2.75 to 1.00             .50%                  .25%
Greater than 2.75 to 1.00                      .75%                  .35%
</TABLE>


         SECTION 2.07. ADDITIONAL INTEREST ON EURODOLLAR RATE ADVANCES. The
Borrower shall pay to each Bank, so long as such Bank shall be required under
regulations of the Board of Governors of the Federal Reserve System to maintain
reserves with respect to liabilities or assets consisting of or including
Eurocurrency Liabilities, additional interest on the unpaid principal amount of
each Advance of such Bank during such periods as such Advance is a Eurodollar
Rate Advance, from the date of such Advance until such principal amount is paid
in full, at an interest rate per annum equal at all times to the remainder
obtained by subtracting (i) the Eurodollar Rate for such Interest Period for
such Eurodollar Rate Advance from (ii) the rate obtained by dividing such
Eurodollar Rate by a percentage equal to 100% minus the Eurodollar Rate Reserve
Percentage of such Bank for such Interest Period, payable on each date on which
interest is payable on such Eurodollar Rate Advance. Such additional interest
shall be determined by such Bank and notified to the Borrower through the Agent.

         SECTION 2.08. INTEREST RATE DETERMINATION AND PROTECTION. (a) The Agent
shall give prompt notice to the Borrower and the Banks of the applicable
interest rate determined by the Agent for purposes of section 2.06(a) or (b).

         (b) If, with respect to any Eurodollar Rate Advances, Banks having at
least 50% of the Commitments notify the Agent that the Eurodollar Rate for any
Interest Period for such Advances will not adequately reflect the cost to such
Banks of making, funding or maintaining their respective Eurodollar Rate
Advances for such Interest Period, the Agent shall forthwith so notify the
Borrower and the Banks, whereupon

                  (i) each Eurodollar Rate Advance will automatically, on the
         last day of the then existing Interest Period therefor, Convert into an
         Adjusted Base Rate Advance, and

                  (ii) the obligation of the Banks to make, or to Convert
         Advances into, Eurodollar Rate Advances shall be suspended until the
         Agent shall notify the Borrower and the Banks that the circumstances
         causing such suspension no longer exist.

                                       13
<PAGE>   18

         (c) If the Borrower shall fail to select the duration of any Interest
Period for any Eurodollar Rate Advances in accordance with the provisions
contained in the definition of "Interest Period" in section 1.01, the Agent will
forthwith so notify the Borrower and the Banks and such Advances will
automatically, on the last day of the then existing Interest Period therefor,
Convert into Adjusted Base Rate Advances.

         (d) On the date on which the aggregate unpaid principal amount of
Advances comprising any Borrowing shall be reduced, by payment or prepayment or
otherwise, to less than $3,000,000, such Advances shall, if they are Advances of
a Type other than Adjusted Base Rate Advances, automatically Convert into
Adjusted Base Rate Advances, and on and after such date the right of the
Borrower to Convert such Advances into Advances of a Type other than Adjusted
Base Rate Advances shall terminate; PROVIDED, HOWEVER, that if and so long as
each such Advance shall be of the same Type and have the same Interest Period as
Advances comprising another Borrowing or other Borrowings, and the aggregate
unpaid principal amount of all such Advances shall equal or exceed $3,000,000,
the Borrower shall have the right to continue all such Advances as, or to
Convert all such Advances into, Advances of such Type having such Interest
Period.

         SECTION 2.09. VOLUNTARY CONVERSION OF ADVANCES. The Borrower may on any
Business Day, upon notice given to the Agent not later than 11:00 A.M.
(Cleveland, Ohio time) on the third Business Day prior to the date of the
proposed Conversion and subject to the provisions of sections 2.08 and 2.12,
Convert all Advances of one Type comprising the same Borrowing into Advances of
another Type; PROVIDED, HOWEVER, that any Conversion of any Eurodollar Rate
Advances into Adjusted Base Rate Advances shall be made on, and only on, the
last day of an Interest Period for such Eurodollar Rate Advances. Each such
notice of a Conversion shall, within the restrictions specified above, specify
(i) the date of such Conversion, (ii) the Advances to be Converted, and (iii) if
such Conversion is into Eurodollar Rate Advances, the duration of the Interest
Period for each such Advance.

         SECTION 2.10. PREPAYMENTS. The Borrower may, upon at least one Business
Day's notice to the Agent stating the proposed date and aggregate principal
amount of the prepayment, and if such notice is given the Borrower shall, prepay
the outstanding principal amounts of the Advances comprising part of the same
Borrowing in whole or ratably in part, together with accrued interest to the
date of such prepayment on the principal amount prepaid; PROVIDED, HOWEVER, that
(x) each partial prepayment shall be in an aggregate principal amount not less
than $3,000,000 and in the event of such prepayment of any Eurodollar Rate
Advance, the Borrower shall be obligated to reimburse the Banks in respect
thereof pursuant to section 8.04(b).

         SECTION 2.11. INCREASED COSTS. (a) If, due to either (i) the
introduction of or any change (other than any change by way of imposition or
increase of reserve requirements, in the case of Eurodollar Rate Advances,
included in the Eurodollar Rate Reserve Percentage) in or in the interpretation
of any law or regulation or (ii) the compliance with any guideline or request
from any central bank or other governmental authority (whether or not having the
force of law), there shall be any increase in the cost to any Bank of agreeing
to make or making, funding or maintaining Eurodollar Rate Advances, then the
Borrower shall from time to time, upon demand by such Bank (with a copy of such
demand to the Agent), pay to the Agent for the account of such Bank additional
amounts sufficient to compensate such Bank for such increased cost. A
certificate as to the amount of such increased cost, submitted to the Borrower
and the Agent by such Bank, shall be conclusive and binding for all purposes,
absent manifest error.

         (b) If any Bank determines that compliance with any law or regulation
or any guideline or request from any central bank or other governmental
authority (whether or not having the force of law) affects or would affect the
amount of capital required or expected to be maintained by such Bank or any
corporation controlling such Bank and that the amount of such capital is
increased by or based upon the existence of such Bank's commitment to lend
hereunder and other commitments of this type, then, upon demand by such Bank
(with a copy of such demand to the Agent), the Borrower shall immediately pay to
the Agent for the account of such Bank, from time to time as specified by such
Bank, additional amounts sufficient to compensate such Bank or such corporation
in the light of such circumstances, to the extent that such Bank reasonably
determines such increase in capital to be allocable to the existence of such
Bank's commitment to lend hereunder. A certificate


                                       14

<PAGE>   19

as to such amounts submitted to the Borrower and the Agent by such Bank shall be
conclusive and binding for all purposes, absent manifest error.

         SECTION 2.12. ILLEGALITY. Notwithstanding any other provision of this
Agreement, if any Bank shall notify the Agent that the introduction of or any
change in or in the interpretation of any law or regulation makes it unlawful,
or any central bank or other governmental authority asserts that it is unlawful,
for any Bank or its Eurodollar Lending Office to perform its obligations
hereunder to make Eurodollar Rate Advances or to fund or maintain Eurodollar
Rate Advances hereunder, (i) the obligation of the Banks to make, or to Convert
Advances into, Eurodollar Rate Advances shall be suspended until the Agent shall
notify the Borrower and the Banks that the circumstances causing such suspension
no longer exist and (ii) the Borrower shall forthwith prepay in full all
Eurodollar Rate Advances of all Banks then outstanding, together with interest
accrued thereon, unless the Borrower, within five Business Days of notice from
the Agent, Converts all Eurodollar Rate Advances of all Banks then outstanding
into Adjusted Base Rate Advances in accordance with section 2.09.

         SECTION 2.13. PAYMENTS AND COMPUTATIONS. (a) The Borrower shall make
each payment hereunder and under the Notes not later than 11:00 A.M. (Cleveland,
Ohio time) on the day when due in U.S. dollars to the Agent at its address
referred to in section 8.02 in same day funds. The Agent will promptly
thereafter cause to be distributed like funds relating to the payment of
principal or interest or commitment fees ratably (other than amounts payable
pursuant to section 2.07 or 2.11) to the Banks for the account of their
respective Applicable Lending Offices, and like funds relating to the payment of
any other amount payable to any Bank to such Bank for the account of its
Applicable Lending Office, in each case to be applied in accordance with the
terms of this Agreement.

         (b) All computations of interest based on the rate referred to in
clause (i) of the definition of Adjusted Base Rate and of commitment fees shall
be made by the Agent on the basis of a year of 365 or 366 days, as the case may
be, and all computations of interest based on the Eurodollar Rate or the Federal
Funds Rate shall be made by the Agent, and all computations of interest pursuant
to section 2.07 shall be made by a Bank, on the basis of a year of 360 days, in
each case for the actual number of days (including the first day but excluding
the last day) occurring in the period for which such interest or commitment fees
are payable. Each determination by the Agent (or, in the case of section 2.07,
by a Bank) of an interest rate hereunder shall be conclusive and binding for all
purposes, absent manifest error.

         (c) Whenever any payment hereunder or under the Notes shall be stated
to be due on a day other than a Business Day, such payment shall be made on the
next succeeding Business Day, and such extension of time shall in such case be
included in the computation of payment of interest or commitment fee, as the
case may be; PROVIDED, HOWEVER, if such extension would cause payment of
interest on or principal of Eurodollar Rate Advances to be made in the next
following calendar month, such payment shall be made on the next preceding
Business Day.

         (d) Unless the Agent shall have received notice from the Borrower prior
to the date on which any payment is due to the Banks hereunder that the Borrower
will not make such payment in full, the Agent may assume that the Borrower has
made such payment in full to the Agent on such date and the Agent may, in
reliance upon such assumption, cause to be distributed to each Bank on such due
date an amount equal to the amount then due such Bank. If and to the extent the
Borrower shall not have so made such payment in full to the Agent, each Bank
shall repay to the Agent forthwith on demand such amount distributed to such
Bank together with interest thereon, for each day from the date such amount is
distributed to such Bank until the date such Bank repays such amount to the
Agent, at the Federal Funds Rate.

         SECTION 2.14. SHARING OF PAYMENTS, ETC. If any Bank shall obtain any
payment (whether voluntary, involuntary, through the exercise of any right of
set-off, or otherwise) on account of the Advances made by it (other than
pursuant to section 2.07 or 2.11) in excess of its ratable share of payments on
account of the Advances obtained by all the Banks, such Bank shall forthwith
purchase from the other Banks such participations in the Advances made by them
as shall be necessary to cause such purchasing Bank to share the excess payment
ratably with each of them, PROVIDED, HOWEVER, that if all or any portion of such
excess payment is thereafter


                                       15

<PAGE>   20

recovered from such purchasing Bank, such purchase from each Bank shall be
rescinded and such Bank shall repay to the purchasing Bank the purchase price to
the extent of such recovery together with an amount equal to such Bank's ratable
share (according to the proportion of (i) the amount of such Bank's required
repayment to (ii) the total amount so recovered from the purchasing Bank) of any
interest or other amount paid or payable by the purchasing Bank in respect of
the total amount so recovered. The Borrower agrees that any Bank so purchasing a
participation from another Bank pursuant to this section 2.14 may, to the
fullest extent permitted by law, exercise all its rights of payment (including
the right of set-off) with respect to such participation as fully as if such
Bank were the direct creditor of the Borrower in the amount of such
participation.


                                   ARTICLE III

                              CONDITIONS OF LENDING

         SECTION 3.01. CONDITIONS PRECEDENT AT RESTATEMENT EFFECTIVE DATE. This
Agreement shall not become effective in accordance with section 8.06 hereof
unless, at and as of the Restatement Effective Date, the Agent shall have
received the following, each dated the Restatement Effective Date or as of a
date not more than five days prior thereto, in form and substance satisfactory
to the Agent and the Majority Banks and (except for the Notes) in sufficient
copies for each Bank:


                  (a) The Notes to the order of the Banks, respectively.

                  (b) Certified copies of the resolutions of the Board of
         Directors of the Borrower approving this Agreement, and of all
         documents evidencing other necessary corporate action and governmental
         approvals, if any, with respect to this Agreement.

                  (c) A certificate of the Secretary or an Assistant Secretary
         of the Borrower certifying the names and true signatures of the
         officers of the Borrower authorized to sign this Agreement, the Notes
         and the other documents to be delivered hereunder.

                  (d) A favorable opinion of John P. Siegfried, General Counsel
         and Secretary of the Borrower, substantially in the form of Exhibit C
         hereto and as to such other matters as any Bank through the Agent may
         reasonably request.

                  (e) Federal Reserve Form U-1 provided for in Regulation U
         issued by the Board of Governors of the Federal Reserve System, the
         statements made in which shall be such as to permit the transactions
         contemplated hereby in accordance with said Regulation U.

         SECTION 3.02. CONDITIONS PRECEDENT TO EACH BORROWING. The obligation of
each Bank to make an Advance on the occasion of each Borrowing shall be subject
to the conditions precedent that on the date of such Borrowing (i) the following
statements shall be true (and each of the giving of the applicable Notice of
Borrowing and the acceptance by the Borrower of the proceeds of such Borrowing
shall constitute a representation and warranty by the Borrower that on the date
of such Borrowing such statements are true):

                  (a) the representations and warranties contained in section
         4.01 of this Agreement are correct on and as of the date of such
         Borrowing, before and after giving effect to such Borrowing and to the
         application of the proceeds therefrom, as though made on and as of such
         date, and

                  (b) no event has occurred and is continuing, or would result
         from such Borrowing or from the application of the proceeds therefrom,
         which constitutes an Event of Default or would constitute an Event of
         Default but for the requirement that notice be given or time elapse or
         both;

and (ii) the Agent shall have received such other approvals, opinions or
documents as any Bank through the Agent may reasonably request.


                                       16

<PAGE>   21

                                   ARTICLE IV

                         REPRESENTATIONS AND WARRANTIES


         SECTION 4.01. REPRESENTATIONS AND WARRANTIES OF THE BORROWER. The
Borrower represents and warrants as follows:

         (a) ORGANIZATION AND AUTHORITY OF THE BORROWER. The Borrower is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Ohio and has all requisite power and authority to own or hold
under lease, to carry on its business as now conducted and proposed to be
conducted, to enter into this Agreement, to issue the Notes and to perform its
obligations under this Agreement and the Notes. The Borrower has, by all
necessary corporate action (all action of shareholders, if any, required
therefor having been duly taken), duly authorized the execution and delivery of
this Agreement and the Notes and the performance of its obligations under this
Agreement.

         (b) SUBSIDIARIES. Each Subsidiary is a corporation duly organized,
validly existing and in good standing under the laws of the jurisdiction of its
incorporation and has all requisite power and authority to own or hold under
lease and to operate the property it purports to own or hold under lease and to
carry on its business as now conducted and as proposed to be conducted. At the
date hereof, each Subsidiary is a Restricted Subsidiary.

         (c) QUALIFICATION. Each of the Borrower and its Subsidiaries is duly
qualified or licensed and in good standing as a foreign corporation duly
authorized to do business in each jurisdiction (other than the jurisdiction of
its incorporation) in which the nature of its activities or the character of the
properties it owns or leases makes such qualification necessary and where
failure so to qualify would, in any case, have a Material Adverse Effect.

         (d) FINANCIAL STATEMENTS. The Borrower has furnished to each Bank
complete and correct copies of (a) its annual report on Form 10-K for the fiscal
year ended December 31, 1994 and (b) its quarterly report on Form 10-Q for the
fiscal quarter ended September 30, 1995. All financial statements included in
the materials described in the preceding sentence, and all related schedules and
notes, have been prepared in accordance with GAAP, in each case applied on a
consistent basis throughout the periods specified (except for changes
specifically noted therein), and present fairly the financial position of the
corporation or corporations to which they relate as at the respective dates
thereof and the results of operations of such corporation or corporations for
the respective periods specified.

         (e) CHANGES, ETC. Since the date of the most recent audited
consolidated balance sheet referred to in section 4.01(d), (i) there has been no
change in the Business or Condition of the Borrower or any Subsidiary from that
reflected in the most recent audited consolidated balance sheet referred to in
section 4.01(d), which change has been, either in any one case or in the
aggregate, Materially Adverse to the Borrower or to the Borrower and its
Subsidiaries taken as a whole, and (ii) neither the business, operations,
properties nor earnings of the Borrower, or of the Borrower and its Subsidiaries
taken as a whole, has been affected as a result of any occurrence or development
(whether or not insured against) to an extent that is Materially Adverse to the
Borrower, or the Borrower and its Subsidiaries taken as a whole.

         (f) TITLE TO PROPERTY. The Borrower and its Subsidiaries have good and
marketable title to their respective real properties and good title to the other
material properties they purport to own, including that reflected in the most
recent audited balance sheet referred to in section 4.01(d) or purported to have
been acquired by the Borrower or any of its Subsidiaries after said date (other
than properties disposed of in the ordinary course of business), subject in the
case of all such property to no Liens other than those permitted by section
5.12. The Borrower and its Subsidiaries enjoy peaceful and undisturbed
possession under all leases of all personal and all real property under which
they operate, and all such leases are valid and subsisting and in


                                       17

<PAGE>   22


full force and effect and neither the Borrower nor any of its Subsidiaries is in
default in any material respect in the performance and observance of its
obligations under any provisions thereof; PROVIDED that (i) any money due or the
value of any property lost as a result of any default under or termination of
such lease or leases shall not exceed $200,000 in the aggregate, and (ii) the
default under or termination of such lease or leases would not, alone or in the
aggregate, have a Material Adverse Effect.

         (g) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the Borrower nor
any Subsidiary is in violation of any term or provision of its corporate charter
or by-laws. Neither the Borrower nor any Subsidiary is in violation of any term
or provision of any agreement, indenture, mortgage or instrument to which it is
a party or by which it or any of its properties may be bound or affected, nor is
it in violation of any existing law, governmental rule or regulation or any
Order of any court, arbitrator or Governmental Body applicable to it (including,
without limitation, any law, rule, regulation or Order relating to environmental
protection, occupational health and safety standards, consumer protection, and
equal employment practice requirements), the consequences of which violation,
either in any one case or in the aggregate, could have a Material Adverse Effect
on the Borrower or on the Borrower and its Subsidiaries taken as a whole.
Neither the execution and delivery of this Agreement and the Notes nor the
consummation of the transactions contemplated hereby nor the performance of the
terms and provisions thereof will result in any breach of, or constitute a
default under, or result in (or require) the creation of any Lien in respect of
any property of the Borrower or any of its Subsidiaries under, any agreement,
indenture, mortgage, instrument, corporate charter or by-law to which the
Borrower or any of its Subsidiaries is a party or by which the Borrower, any of
its Subsidiaries or any of their respective properties may be bound or affected,
or violate any existing law, governmental rule or regulation or any Order of any
court, arbitrator or Governmental Body applicable to the Borrower or any of its
Subsidiaries which could have a Material Adverse Effect on the Borrower or on
the Borrower and its Subsidiaries taken as a whole. Neither the Borrower nor any
Subsidiary is a party to or bound by any instrument or agreement which contains
any restrictions on the incurrence by the Borrower of any Debt other than this
Agreement and the Reimbursement Agreement, dated as of October 1, 1992, between
the Borrower and PNC Bank, National Association.

         (h) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
authorization of, or registration, filing or declaration with, any Governmental
Body is required on the part of the Borrower for the valid execution and
delivery of this Agreement or the consummation of the transactions contemplated
thereby, including the issuance and delivery by the Borrower of the Notes, or
for the fulfillment of, or compliance by the Borrower with, the terms and
provisions of this Agreement and the Notes.

         (i) LITIGATION. There are no actions, suits or proceedings pending or,
to the knowledge of the Borrower, threatened against or affecting the Borrower,
any Subsidiary or any of their respective properties (or any reasonable basis
therefor known to the Borrower) in any court or before any arbitrator of any
kind or before or by any Governmental Body, which questions the validity of this
Agreement or the Notes or any action taken or to be taken pursuant thereto or
which might result, either in any one case or in the aggregate, in an impairment
of the ability of the Borrower to perform its obligations under the Agreement or
the Notes, or, if determined adversely to the Borrower or a Subsidiary, in a
Material Adverse Change in the Business or Condition of the Borrower or of the
Borrower and its Subsidiaries taken as a whole.

         (j) PATENTS, TRADEMARKS, AUTHORIZATIONS, ETC. The Borrower and its
Restricted Subsidiaries own, possess or have the right to use (without any known
conflict with the rights of others) all franchises, patents, trademarks, service
marks, trade names, copyrights, licenses, permits and authorizations which are
necessary to the conduct of their respective businesses as conducted on the date
hereof and as proposed to be conducted the lack of which would have a Material
Adverse Effect.

         (k) TAXES. The Borrower and its Subsidiaries have filed all tax returns
which are required by law to have been filed and have paid all taxes,
assessments, fees and charges of each Governmental Body shown to be due and
payable on such returns to the extent the same have become due and payable and
before they have become delinquent other than (i) those presently payable
without penalty or interest, (ii) those being contested in good faith by
appropriate proceedings with respect to which adequate reserves have been
established in 

                                       18
<PAGE>   23

accordance with GAAP and (iii) those the nonfiling of which would not have a
Material Adverse Effect. The federal income tax returns of the Borrower and its
Subsidiaries have been examined and reported on by the taxing authorities or
closed by applicable statute for all fiscal years through the fiscal year ended
December 31, 1985. In the opinion of the Borrower all tax liabilities are
adequately provided for on the books of the Borrower and its Subsidiaries in
accordance with GAAP.

         (l) COMPLIANCE WITH ERISA. (A) Except as provided in Schedule II to
this Agreement, no Termination Event has occurred, and no event or condition has
occurred or exists with respect to which any Termination Event would reasonably
be expected to occur, and no accumulated funding deficiency (as defined in
section 302 of ERISA and section 412 of the Code), whether or not waived, has
occurred with respect to any Plan. The present value of all accrued benefits
under each Plan other than a Multiemployer Plan (based on those assumptions used
to fund such Plan, which assumptions are reasonable in the aggregate) did not,
as of the most recent valuation date, which for any such Plan was no earlier
than twelve months prior to the date as of which the representation is made,
exceed the then current value of the assets of such Plan allocable to such
benefits.

         (B) Except as provided in Schedule II to this Agreement, no Company
Group Member has incurred, or is reasonably expected to incur, any withdrawal
liability to any Multiemployer Plan. No Company Group Member has received any
notification that any Multiemployer Plan is in reorganization (as defined in
section 4241 of ERISA), is insolvent (as defined in section 4245 of ERISA) or
has been terminated, within the meaning of Title IV of ERISA, and no
Multiemployer Plan is reasonably expected to be in reorganization or insolvent
or to be terminated.

         (C) No Company Group Member has participated in any prohibited
transaction (as defined in section 406 of ERISA or section 4975 of the Code),
which has subjected it or would reasonably be expected to subject it
to any civil penalty or tax imposed by section 502(i) of ERISA or section 4975
of the Code, respectively. No Company Group Member has incurred any liability or
has been subjected to any civil penalty pursuant to section 409 or 502(1) of
ERISA, respectively, and no event or condition has occurred or exists with
respect to which any such liability or civil penalty would reasonably be
expected to occur. No Company Group Member has incurred, or is reasonably
expected to incur, any liability to the PBGC (other than for insurance premiums,
which have been paid when due).

         (D) Full payment has been made on or before the due date thereof of all
amounts which any Company Group Member is or was required under the terms of
each Plan to have paid as contributions to such Plan as of the date hereof.

         (E) No lien imposed under the Code or ERISA on the assets of any
Company Group Member exists or would reasonably be expected to arise on account
of any Plan.

         (F) The present annual cost to the Company Group Members for providing
post-retirement medical, dental or death benefits to their current and former
employees under all welfare benefit plans (as defined in section 3(1) of ERISA)
does not, in the aggregate, exceed $2,500,000. No event or condition exists or
is reasonably expected to arise which would reasonably be expected to result in
a material increase in such annual cost beyond the increase normally expected in
the normal course of business for the industry in which the Borrower does
business. Each such plan to which sections 601-609 of ERISA and section 4980B of
the Code apply has been administered in material compliance with such sections.

         (G) The execution and delivery of this Agreement and the Borrowings
contemplated hereby will not involve any transaction (i) which is subject to the
prohibitions of section 406 of ERISA and with respect to which a civil penalty
pursuant to section 502(i) of ERISA could be imposed, or (ii) in connection with
which a tax could be imposed pursuant to section 4975 of the Code.


                                       19
<PAGE>   24

         (m) VALIDITY OF THIS AGREEMENT, ETC. This Agreement is, and each Note
when delivered hereunder will be, a legal, valid and binding obligation of the
Borrower enforceable against the Borrower in accordance with its respective
terms.

         (n) USE OF PROCEEDS; MARGIN REGULATIONS. The proceeds of the Advances
made hereunder will be used by the Borrower for general corporate purposes,
including (without limitation) repurchases by the Borrower of shares of its
outstanding Common Stock. Notwithstanding the foregoing, no proceeds of any
Advance will be used, directly or indirectly, to acquire any equity security of
a class which is registered pursuant to Section 12 of the Securities Exchange
Act of 1934, or to make any voluntary prepayment of (or to purchase or otherwise
acquire) any of the Convertible Subordinated Notes, except that the Borrower may
use proceeds of Advances hereunder to directly or indirectly finance the
repurchases by the Borrower of up to $10,000,000 (based on the repurchase
prices) of its Common Stock where such usage would not cause the transactions
hereunder to violate any of the provisions of Regulation U of the Board of
Governors of the Federal Reserve System. Neither the Borrower nor any of its
Subsidiaries is engaged in the business of extending credit for the purpose of
purchasing or carrying margin stock (as such term is defined in such Regulation
U), and no proceeds of any Advance will be used to extend credit to others for
the purpose of purchasing or carrying any margin stock. Following the
application of the proceeds of any Advance, not more than 25% of the value of
the assets (either of the Borrower only or of the Borrower and its Subsidiaries
on a consolidated basis) will be margin stock.

         (o) STATUS UNDER CERTAIN STATUTES. The Borrower is not an "investment
company" or a Person directly or indirectly "controlled" by or "acting on behalf
of" an "investment company" within the meaning of the Investment Company Act of
1940, as amended. The Borrower is not a "holding company", or a "subsidiary
company" of a "holding company", or an "affiliate" of a "holding company" or of
a "subsidiary company" of a "holding company", as such terms are defined in the
Public Utility Holding Company Act of 1935, as amended.

         (p) DISCLOSURE. Neither this Agreement, nor any other document,
certificate or instrument delivered to the Banks by or on behalf of the Borrower
in connection with the transactions contemplated by this Agreement,
contains any untrue statement of a material fact or omits to state a material
fact necessary in order to make the statements contained herein or therein not
misleading. There is no fact known to the Borrower which Materially Adversely
Affects or in the future may (so far as the Borrower can now reasonably foresee)
Materially Adversely Affect the Business or Condition of the Borrower and its
Subsidiaries taken as a whole, which has not been set forth or reflected in this
Agreement or in the other documents, certificates and instruments referred to
herein and delivered to the Banks by or on behalf of the Borrower in connection
with the transactions contemplated by this Agreement.


                                    ARTICLE V

                            COVENANTS OF THE BORROWER

         SECTION 5.01. FINANCIAL STATEMENTS; INFORMATION. So long as any Note
shall remain unpaid or any Bank shall have any Commitment hereunder, unless the
Majority Banks shall otherwise consent in writing, the Borrower will furnish to
each Bank:

                  (a) as soon as practicable and in any event within 45 days
         after the end of each of the first three quarterly fiscal periods in
         each fiscal year of the Borrower, an unaudited consolidated balance
         sheet of the Borrower and its Restricted Subsidiaries, in each case as
         of the end of such quarterly period and the related unaudited
         consolidated statements of income, shareholders equity and cash flows
         of the Borrower and its Restricted Subsidiaries for such period, and
         (in the case of the first, second and third such quarterly periods) for
         the portion of the fiscal year ended with the last day of such
         quarterly period, setting forth in each case in comparative form the
         figures for the corresponding periods of the previous fiscal year, all
         in reasonable detail and certified by the principal financial officer
         of the Borrower;

                                       20

<PAGE>   25

                  (b) as soon as practicable and in any event within 90 days
         after the end of each fiscal year of the Borrower, a consolidated
         balance sheet of the Borrower and its Restricted Subsidiaries, in each
         case as of the end of such year and the related consolidated statements
         of income, shareholders' equity and cash flows of the Borrower and its
         Restricted Subsidiaries for such fiscal year, setting forth in each
         case in comparative form the respective figures for the previous fiscal
         year, all in reasonable detail and accompanied by a report thereon of
         independent certified public accountants of recognized national
         standing, who may be the present regular auditors of the books of the
         Borrower, which report shall not be made in reliance upon the opinion
         of any other accountant (other than an opinion regarding the financial
         statements of any Person for any fiscal period ending prior to the time
         such Person became a Subsidiary), shall be made without qualification
         (except for qualifications resulting from changes in accounting
         principles and methods agreed to by such accountants), shall comply
         with generally accepted auditing standards at the time in effect and
         shall state that such financial statements present fairly, in all
         material respects, the consolidated financial position of the Borrower
         and its Restricted Subsidiaries as at the dates indicated and the
         results of their operations for the periods indicated and have been
         prepared in accordance with GAAP applied on a basis consistent with
         prior years (except for changes in application in which such
         accountants concur and which are noted in such financial statements)
         and that the examination of such accountants has been made in
         accordance with generally accepted auditing standards, and accordingly
         included such tests of the accounting records and such other auditing
         procedures as were considered necessary in the circumstances;

                  (c) together with each delivery of financial statements
         pursuant to clause (a) or (b) of this section, an Officer's
         Certificate:

                           (i) stating that the officer executing the same on
                  behalf of the Borrower has reviewed the terms of this
                  Agreement and of the Notes and has made, or caused to be made
                  under his supervision, a review in reasonable detail of the
                  transactions and conditions of the Borrower and its
                  Subsidiaries during the accounting period covered by such
                  financial statements, and that such review has not disclosed
                  the existence during or at the end of such accounting period,
                  and that such officer does not have knowledge of the existence
                  as at the date of such Officer's Certificate, of any condition
                  or event which constitutes a Default or an Event of Default,
                  or, if any such condition or event existed or exists,
                  specifying the nature and period of existence thereof and what
                  action the Borrower has taken or is taking or proposes to take
                  with respect thereto;

                           (ii) setting forth, as of the date of such balance
                  sheet or for such period, as the case may be, (A) the
                  respective amounts (showing the calculations thereof) of
                  Attributable Debt, Consolidated Current Assets, Consolidated
                  Current Liabilities, Consolidated Income Tax Expense,
                  Consolidated Interest Expense, Consolidated Funds from
                  Operations, Consolidated Liabilities, Consolidated Net Income
                  (determined both with and without reference to clause (iii) of
                  the definition of such term), Consolidated Tangible Net Worth,
                  Consolidated Total Debt, Current Debt, Priority Debt, Total
                  Capitalization and (B) the aggregate principal amount of
                  outstanding Debt of all Subsidiaries and outstanding Debt
                  secured by Liens permitted by section 5.13, and

                           (iii) setting forth, as of the date of such balance
                  sheet or for such period, as the case may be, facts or
                  computations in reasonable detail demonstrating compliance
                  with the restrictions contained in sections 5.07, 5.08, 5.09,
                  5.10, 5.11, 5.12, 5.13, 5.14, 5.15, 5.16 and 5.17;

                  (d) together with each delivery of annual financial statements
         pursuant to clause (b) of this section, a written statement by the
         independent public accountants referred to in said clause (b) who have
         reported on such financial statements

                           (i) stating whether, in the course of their audit
                  examination or otherwise, anything has come to their attention
                  concerning the existence during the fiscal year covered by
                  such


                                       21
<PAGE>   26



                  financial statements (and stating whether they have
                  knowledge of the existence as of the date of such accountants'
                  written statement) of any condition or event which constitutes
                  a Default or an Event of Default, and if so, specifying the
                  nature and period of existence thereof; and

                           (ii) stating that they have examined the Officer's
                  Certificate delivered in connection with such annual financial
                  statements pursuant to clause (c) of this section and based
                  upon their audit examination nothing has come to their
                  attention which causes them to believe that the information
                  contained in such Officer's Certificate is not correct or that
                  the matters set forth in such Officer's Certificate in
                  connection with such annual financial statements have not been
                  properly stated in accordance with the terms of this
                  Agreement;

                  (e) promptly upon receipt thereof (and in any event within
         five Business Days thereafter), copies of all reports submitted to the
         Borrower by independent public accountants in connection with any
         annual, interim or special audit of the Borrower made by such
         accountants, but, excluding, subject to clause (k) of this section, the
         following:

                           (1) Management letters; 
                           (2) Management consulting reports; 
                           (3) Reports for a committee of Board of Directors; 
                           (4) Negative assurance comfort letters; and 
                           (5) Special purpose trust funds;

                  (f) promptly upon their becoming available (and in any event
         within five Business Days thereafter), copies of (i) all financial
         statements, reports, notices, proxy statements and other information
         sent or made available generally by the Borrower to any class of its
         security holders or by any Subsidiary to any class of its security
         holders other than the Borrower or another Subsidiary, (ii) all regular
         and periodic reports (including reports on Form 8-K) and any
         registration statements and prospectuses filed by the Borrower or any
         of its Subsidiaries with any securities exchange or with the Commission
         and (iii) all press releases and other statements made available
         generally by the Borrower or any Subsidiary to the public concerning
         material developments in the business of the Borrower or its
         Subsidiaries;

                  (g) immediately upon any officer of the Borrower obtaining
         knowledge of any condition or event which constitutes a Default or an
         Event of Default, or becoming aware that the holder of any Note has
         given any notice or taken any other action with respect to a claimed
         Default or Event of Default or that any Person has given any notice to
         the Borrower or any Restricted Subsidiary or taken any other action
         with respect to a claimed default or event or condition under or in
         respect of any Debt referred to in section 6.01(e) or with respect to
         the occurrence or existence of any event or condition of the type
         referred to in section 6.01(f) or (g), an Officers' Certificate
         specifying the nature and period of existence thereof and what action
         the Borrower has taken or is taking or proposes to take with respect
         thereto;

                  (h) if and when any Company Group Member (i) knows or in good
         faith has reason to know of the occurrence of any Termination Event,
         (ii) with respect to any Multiemployer Plan, receives notice as
         prescribed in ERISA of any withdrawal liability assessed against any
         Company Group Member or of a determination that any Multiemployer Plan
         is in reorganization or insolvent (both within the meaning of Title IV
         of ERISA), (iii) knows or in good faith has reason to know that a
         prohibited transaction (as defined in section 406 of ERISA or section
         4975 of the Code) has occurred involving any Company Group Member, or
         (iv) knows or in good faith has reason to know that there has been a
         material adverse change in the funding status of any Plan after which
         such Plan shall have an Unfunded Current Liability, a description of
         such event or a copy of such notice and a statement by the principal
         financial officer of the Borrower of the action which is proposed to be
         taken with respect thereto as soon as practicable and in any event
         within ten days thereafter;
                                       22
<PAGE>   27


                  (i) promptly (and in any event within five Business Days)
         after any officer of the Borrower obtains knowledge of any litigation,
         administrative proceeding or judgment affecting the Borrower or any of
         its Subsidiaries (whether or not considered by the Borrower to be
         covered by insurance) which, in the reasonable opinion of the Borrower,
         has a reasonable possibility of being adversely determined or has been
         adversely determined in an amount that would have a Material Adverse
         Effect, or would materially impair the ability of the Borrower to
         perform its obligations under this Agreement or the Notes, an Officer's
         Certificate specifying in reasonable detail the facts and circumstances
         surrounding such litigation, proceeding or judgment;

                  (j) promptly (and in any event within five Business Days)
         after any officer of the Borrower obtains knowledge of any complaint,
         suit, proceeding, penalty assessed, order or request for information
         (such request for information having been requested by any Governmental
         Body) under any applicable Environmental Law, or of any material
         development in respect of any such complaint, suit, proceeding, penalty
         assessed, or order, affecting the Borrower or any of its Subsidiaries,
         except any such complaint, suit, proceeding, penalty assessed, order,
         or development which, in the reasonable opinion of the Borrower, does
         not have a reasonable possibility of being adversely determined in an
         amount or with an effect that would have a Material Adverse Effect, an
         Officers' Certificate specifying such complaint, suit, proceeding,
         penalty assessed, order or material development in respect thereof, as
         the case may be, and what action the Borrower has taken or is taking or
         proposes to take with respect thereto; and

                  (k) promptly upon request therefor (i) such other financial
         information or environmental information concerning the Borrower or any
         of its Subsidiaries as any Bank or any other institutional holder of
         any Note may from time to time reasonably request, and (ii) in the
         event of a reasonable business concern that any Bank or any other
         institutional holder of a Note may have concerning the Borrower or any
         of its Subsidiaries, any other information as to the Business or
         Condition of the Borrower or any of its Subsidiaries as any Bank or any
         other institutional holder of a Note may from time to time reasonably
         request, EXCLUDING in any case information on pricing, market share and
         individual plant costs.

         SECTION 5.02. INSPECTION OF PROPERTIES AND BOOKS. Each Bank and its
representatives may visit and inspect any of the properties of the Borrower and
its Subsidiaries, including their respective books of account, records, reports
and other papers, make copies and extracts therefrom, and discuss their affairs,
finances and accounts with their respective officers and independent public
accountants (and the Borrower hereby authorizes and directs each such officer
and independent public accountant to engage in such discussion), during business
hours and upon reasonable notice to the Borrower and as often as may be
reasonably requested; PROVIDED, that it being understood and agreed that if any
Event of Default shall have occurred and be continuing, the expenses incurred in
connection with any visit and inspection pursuant to this section shall be for
the Borrower's account.

     SECTION 5.03. CORPORATE EXISTENCE; PAYMENT OF TAXES; MAINTENANCE OF
PROPERTIES; INSURANCE; COMPLIANCE WITH LAWS, ETC. The Borrower will, and will
cause each Restricted Subsidiary to,

                  (a) do or cause to be done all things necessary to preserve
         and keep in full force and effect its corporate existence (except as
         otherwise permitted by section 5.08) and its licenses, rights (charter
         and statutory) and franchises, except that, subject to compliance with
         section 5.07 and 5.08, the licenses, rights and franchises of the
         Borrower or any Restricted Subsidiary may be abandoned, modified or
         terminated if, in the good faith judgment of the Board of Directors,
         such abandonment, modification or termination is in the best interest
         of the Borrower and is not disadvantageous to the holders of the Notes;

                  (b) pay and discharge or cause to be paid and discharged (i)
         all taxes, assessments and governmental charges or levies imposed upon
         it or any of its property (real, personal or mixed) or assets or in
         respect of any of its franchises, business, income or property before
         the same shall become delinquent, and (ii) all claims of landlords,
         carriers, warehousemen, mechanics, materialmen and other similar
         Persons for labor, materials, supplies and rentals which, if unpaid,
         might by law become a Lien

                                       23

<PAGE>   28



         upon any of its properties or assets; PROVIDED, HOWEVER, that the
         failure of the Borrower or any Restricted Subsidiary to pay any such
         tax, assessment, charge, levy or claim shall not constitute a default
         hereunder if and for so long as the amount, applicability or validity
         thereof shall concurrently be contested in good faith by appropriate
         and timely proceedings diligently conducted, and if such reserve or
         other appropriate provision, if any, as shall be required by GAAP shall
         have been made therefor, and if neither the Borrower's nor any such
         Restricted Subsidiary's title to or right to the use of any of its
         property is impaired in any material respect by reason of such contest;

                  (c) maintain and keep, or cause to be maintained and kept, in
         all material respects all licenses, rights, permits and the like used
         or useful in its business, and maintain and keep, or cause to be
         maintained and kept, in good repair, working order and condition
         (ordinary wear and tear excepted), all properties used or useful in its
         business, and from time to time make or cause to be made all needful
         and proper repairs, renewals, replacements and improvements thereof so
         that the business carried on in connection therewith may be properly
         and advantageously conducted in the good faith judgment of the Board of
         Directors;

                  (d) maintain, or cause to be maintained, with financially
         sound and reputable insurers, insurance in respect of its properties
         and business against loss or damage of the kinds customarily insured
         against by prudent corporations of established reputation engaged in
         the same or similar business and similarly situated, of such type and
         in such amounts as are customarily carried under similar circumstances
         by such other corporations; and

                  (e) comply in all material respects with all applicable (to
         it, its properties or its operations) laws, statutes, regulations and
         orders of, and all applicable (to it, its properties or its operations)
         restrictions imposed by, any Governmental Body, in respect of the
         conduct of its business and the ownership of its properties (including,
         without limitation, applicable statutes, regulations and orders
         relating to equal employment opportunities or environmental standards
         or controls) with which the failure to so comply would have a Material
         Adverse Effect, except such as are being contested in good faith by
         appropriate and timely proceedings diligently conducted, and if such
         reserve or other appropriate provision, if any, as shall be required by
         GAAP shall have been made therefor and neither the Borrower's nor any
         such Restricted Subsidiary's title to or right to the use of any of its
         property is impaired in any material respect by reason of such contest.

         SECTION 5.04. BOOKS AND ACCOUNTING. The Borrower will (a) keep proper
books of record and account in which full, true and correct entries will be made
of all its business transactions in accordance with GAAP; and (b) maintain a
system of accounting established and administered in accordance with GAAP and
set aside on its books from its earnings for each fiscal year all proper
reserves, accruals and provisions which, in accordance with GAAP, should be set
aside from such earnings in connection with its business, including, without
limitation, provisions for depreciation, obsolescence and/or amortization and
accruals for taxes for such period, including all taxes based on or measured by
income or profits.

         SECTION 5.05. NATURE OF BUSINESS. The Borrower will not, and will not
permit any Restricted Subsidiary to, engage in any line of business, other than
the business of manufacturing construction materials, supplying construction
services and such other business activities and opportunities related thereto,
which the Board of Directors deems consistent with the business strategy of the
Borrower.

         SECTION 5.06. TRANSACTIONS WITH AFFILIATES. The Borrower will not, and
will not permit any Restricted Subsidiary to, directly or indirectly, engage in
any transaction with any Affiliate of the Borrower, other than transactions
entered into in the ordinary course of business and upon terms that are not less
favorable to the Borrower or such Restricted Subsidiary, as the case may be,
than those which might be obtained at the time on an arm's-length transaction
basis from any Person which is not such an Affiliate.





                                       24

<PAGE>   29




         SECTION 5.07.     SUBSIDIARY STOCK AND DEBT; SUBSIDIARY DIVIDENDS.  
         The Borrower will not:

                  (a) directly or indirectly sell, assign, pledge or otherwise
         dispose of any Debt of, or claim against, or any shares of stock or
         similar interests or other securities of (or warrants, rights or
         options to acquire stock or similar interests or other securities of),
         any Restricted Subsidiary, except to the Borrower or any other
         Wholly-owned Restricted Subsidiary or except as directors' qualifying
         shares if required by applicable law;

                  (b) permit any Restricted Subsidiary directly or indirectly to
         sell, assign, pledge or otherwise dispose of any Debt of, or claim
         against, or any shares of stock or similar interests or other
         securities of (or warrants, rights or options to acquire stock or
         similar interests or other securities of), any other Restricted
         Subsidiary, except to the Borrower or any other Wholly-owned Restricted
         Subsidiary or as directors' qualifying shares if required by applicable
         law;

                  (c) permit any Restricted Subsidiary to have outstanding any
         shares of Preferred Stock other than shares of Preferred Stock which
         are owned by the Borrower or a Wholly-owned Restricted Subsidiary;

                  (d) permit any Restricted Subsidiary directly or indirectly to
         issue or sell any shares of its stock or similar interests or other
         securities (or warrants, rights or options to acquire stock or similar
         interests or other securities) except to the Borrower or any other
         Wholly-owned Restricted Subsidiary or as directors' qualifying shares
         if required by applicable law; or

                  (e) enter into, and will not permit any Restricted Subsidiary
         to enter into, or otherwise be subject to, any agreement, including any
         charter or by-law provision, which would limit the amount of, or
         otherwise impose any restriction on the payment of, dividends by any
         Restricted Subsidiary to the Borrower or to any other Restricted
         Subsidiary;

PROVIDED, HOWEVER, that all Debt and stock or similar interests and other
securities of any Restricted Subsidiary owned by the Borrower and its other
Restricted Subsidiaries may be simultaneously sold as an entirety for a cash
consideration at least equal to the fair value thereof (as determined in good
faith by the Board of Directors) at the time of such sale, if (i) such
Restricted Subsidiary being sold does not at the time own any Debt or stock or
similar interests or other securities of (or warrants, rights or options to
acquire stock or similar interests or securities of) any other Restricted
Subsidiary which is not being simultaneously sold as an entirety as permitted by
this section or any Debt of the Borrower, (ii) the assets of such Restricted
Subsidiary represented by the equity interests to be so transferred are such
that the sale of such assets would be permitted by section 5.08 (in which case
such transaction shall be considered and deemed a disposition of assets for the
purposes of section 5.08), and (iii) immediately after the consummation of such
transaction, no Default or Event of Default shall have occurred and be
continuing.

         SECTION 5.08. CONSOLIDATION, MERGER, SALE OF ASSETS, ETC. (a) The
Borrower will not, and will not permit any Restricted Subsidiary to, consolidate
with or merge into any other Person, or permit any other Person to consolidate
with or merge into it, or sell, lease, transfer or otherwise dispose of any part
of its assets to any Person except in the ordinary course of its business (as
such business is conducted in compliance with section 5.05 hereof), except that
if no Default or Event of Default shall have occurred and be continuing or shall
result therefrom:

                  (i) any Restricted Subsidiary may merge or consolidate with
         (x) any other Restricted Subsidiary and, (y) if the Restricted
         Subsidiary is the continuing or surviving corporation, any other
         corporation;

                  (ii) the Borrower may sell, lease, transfer or otherwise
         dispose of its assets to any Wholly- owned Restricted Subsidiary; and
         any Restricted Subsidiary may sell, lease, transfer or otherwise
         dispose


                                       25


<PAGE>   30

         of its assets to the Borrower or any other Restricted Subsidiary, and
         may thereafter liquidate and dissolve;

                  (iii) the Borrower and any Restricted Subsidiary may sell,
         lease, transfer or otherwise dispose of assets in the ordinary course
         of its business; and

                  (iv) the Borrower and any Restricted Subsidiary may sell,
         lease, transfer or otherwise dispose (any such sale, lease, transfer or
         other disposition, an "EXCESS DISPOSITION") of any of its assets, other
         than any sale, lease, transfer or other disposition permitted by
         subsections (a)(ii) and (iii) of this section, whether in a single
         transaction or a series of related transactions, for a consideration
         equal to the greater of the book value or fair market value of such
         assets (as determined in good faith by the Board of Directors) at the
         time of such Excess Disposition, if the aggregate amount of
         Consolidated Funds from Operations attributable to such assets and to
         all assets the subject of any Excess Disposition during the
         twelve-consecutive-month period immediately preceding such Excess
         Disposition, shall not exceed 15% of Consolidated Funds from Operations
         determined as of the end of the fiscal quarter immediately preceding
         such Excess Disposition, PROVIDED, HOWEVER, there shall be excluded
         from any Excess Disposition any sale, lease, transfer or other
         disposition of assets the proceeds of which are (i) applied on or
         before the first anniversary of such Excess Disposition to purchase
         other property or assets which in the judgment of the Board of
         Directors of the Borrower is used or useful in carrying on the business
         of the Borrower and its Restricted Subsidiaries as permitted by section
         5.05 and has, in the judgment of such Board, a fair market value at
         least equal to the proceeds received from such sale, lease, transfer or
         other disposition or (ii) applied, on a PRO RATA basis, to permanently
         reduce the Commitments hereunder and reduce the outstanding principal
         amount of any other Funded Debt of the Borrower which is not
         subordinate to Debt which may be outstanding hereunder, or to the
         extent not so applied on a PRO RATA basis, applied to permanently
         reduce the Commitments hereunder.

         (b) Nothing contained in this section shall permit the disposition of
assets consisting of stock, Debt or other similar interests in or other
securities of (or warrants, rights or options to acquire stock or other
securities of) any Restricted Subsidiary unless such disposition is also made in
compliance with section 5.07.

         SECTION 5.09. SALE-LEASEBACK TRANSACTIONS. The Borrower will not, and
will not permit any of its Restricted Subsidiaries to, enter into any
Sale-Leaseback Transaction, except that if at the time of and immediately after
giving effect to such Sale-Leaseback Transaction no Default or Event of Default
shall have occurred and be continuing, the Borrower and its Restricted
Subsidiaries may enter into Sale-Leaseback Transactions if, (a) immediately
after giving effect to the incurrence of the Attributable Debt in respect of any
such Sale-Leaseback Transaction and the substantially concurrent incurrence or
retirement of other Debt of the Borrower or any Restricted Subsidiary, the
aggregate principal amount outstanding of all Priority Debt does not exceed the
lesser of $5,000,000 and 15% of Total Capitalization or (b) the net proceeds
from the sale of the assets sold in connection with such Sale-Leaseback
Transaction are at least equal to the fair market value of such assets (as
determined in good faith by the Chief Financial Officer and any other executive
officer of the Borrower) and either (i) within one year of such Sale-Leaseback
Transaction, shall be applied or committed (pursuant to a binding commitment in
writing) to the purchase, acquisition or construction of property which is to be
used in the business of the Borrower and its Restricted Subsidiaries as
permitted to be conducted pursuant to section 5.05 or (ii) applied, on a PRO
RATA basis, to permanently reduce the Commitments hereunder and reduce the
outstanding principal amount of any other Funded Debt of the Borrower which is
not subordinate to Debt which may be outstanding hereunder, or to the extent not
so applied on a PRO RATA basis, applied to permanently reduce the Commitments
hereunder.

         SECTION 5.10. MAINTENANCE OF CONSOLIDATED TANGIBLE NET WORTH. The
Borrower will not permit Consolidated Tangible Net Worth at any time to be less
than $35,000,000, EXCEPT that effective as of the end of the Borrower's fiscal
quarter ended December 31, 1994, and as of the end of each fiscal quarter
thereafter, the foregoing amount (as it may from time to time be increased as
herein provided), shall be increased by 50% of Consolidated Net Income for the
fiscal quarter ended on such date, if any (there being no reduction in the case
of any such Consolidated Net Income which reflects a deficit). For purposes of
this Section only, Consolidated


                                       26


<PAGE>   31

Net Income shall be determined without giving effect to clause (iii) of the
definition of the term Consolidated Net Income.

         SECTION 5.11. CURRENT DEBT. The Borrower shall be permitted to incur
Current Debt, PROVIDED that the Borrower will have no Current Debt outstanding
on any day unless during the twelve-consecutive-month period preceding such day,
the aggregate principal amount of the Borrower's Current Debt outstanding shall
have been $5,000,000 or less on each day during a period of at least forty-five
consecutive days. For purposes of this section only, the unpaid principal amount
of the Notes shall be considered Current Debt, and the Borrower's Senior Notes
due 1995, originally issued pursuant to the Note Purchase Agreements, dated as
of December 15, 1990, shall not be considered Current Debt at any time during
the one-year period prior to their scheduled maturity date of December 15, 1995.

         SECTION 5.12. LIENS. The Borrower will not, and will not permit any
Restricted Subsidiary to, directly or indirectly, create, incur, assume or
permit to exist any Lien on or with respect to any property or asset of any
character of the Borrower or any Restricted Subsidiary (whether held on the date
hereof or hereafter acquired) or any interest therein or any income or profits
therefrom, and except for the following:

                  (a) Liens for taxes, assessments or governmental charges or
         levies either not yet due or the payment of which is not at the time
         required by section 5.03(b);

                  (b) Liens of landlords, carriers, warehousemen, mechanics,
         materialmen and other similar Persons incurred in the ordinary course
         of business for sums either not yet due or the payment of which is not
         at the time required by section 5.03(b);

                  (c) Liens (other than any Lien created or imposed under ERISA)
         incurred or deposits made in the ordinary course of business in
         connection with workers' compensation, unemployment insurance and other
         types of social security, or to secure the performance of tenders,
         statutory obligations, surety and appeal bonds, bids, leases,
         government contracts, performance and return-of-money bonds and other
         similar obligations (exclusive in any case of obligations incurred in
         connection with the borrowing of money or the obtaining of advances of
         credit);

                  (d) any attachment or judgment Lien arising in connection with
         court proceedings, PROVIDED that (i) the execution or other enforcement
         of such Lien is effectively stayed and the claims secured thereby are
         being actively contested in good faith and by appropriate proceedings
         diligently conducted, and (ii) such reserve or other appropriate
         provision, if any, as shall be required by GAAP shall have been made
         therefore and neither the Borrower's nor any such Restricted
         Subsidiary's title to or right to use any of its property is impaired
         in any material respect by reason of such contest;

                  (e) easements, licenses, rights-of-way and other rights and
         privileges in the nature of easements and similar Liens incidental to
         the ownership of property and not incurred in connection with the
         borrowing of money or the obtaining of advances or credit, and which do
         not, individually or in the aggregate, interfere with the ordinary
         conduct of the business of the Borrower or any Restricted Subsidiary or
         materially detract from the value of the properties subject to any such
         Liens;

                  (f) Liens existing on the date of this Agreement and securing
         Debt of the Borrower or a Restricted Subsidiary, as identified on
         Schedule III hereto; PROVIDED, HOWEVER, that no such Lien shall be
         extended to any other property or asset of the Borrower or any
         Restricted Subsidiary; and

                  (g) any Lien (including a Capital Lease) created solely to
         secure the deferred purchase price of property or the cost of
         construction on or improvements of property acquired, constructed or
         improved by the Borrower or any Restricted Subsidiary after the date
         hereof, or any Lien (including a Capital Lease) created to secure Debt
         incurred solely for the purpose of financing the acquisition,
         construction or improvement, as the case may be, of such property (if
         such Debt is incurred at the time


                                       27

<PAGE>   32


         of or within 120 days after such acquisition or the completion of such
         construction or improvement), PROVIDED that

                           (i) no such Lien shall at any time extend to or cover
                  any property of the Borrower or any Restricted Subsidiary
                  other than the acquired assets on which it was originally
                  imposed and improvements thereto and proceeds thereof, and

                           (ii) the principal amount of all Debt secured by all
                  such Liens on any such assets shall not at the time of
                  acquisition of such assets exceed an amount equal to the
                  lesser of (A) the cost to the Borrower or such Restricted
                  Subsidiary (including the principal amount of any pre-existing
                  Debt secured by such Liens, whether or not the Borrower or
                  such Restricted Subsidiary has any personal liability with
                  respect thereto) of such assets and (B) the fair market value
                  of such asset (as determined in good faith by the chief
                  financial officer of the Borrower or Restricted Subsidiary) at
                  the time of acquisition thereof;

                  (h) any Lien existing on any asset (i) of any Person at the
         time such Person becomes a Restricted Subsidiary, (ii) of any Person
         existing at the time such Person is merged or consolidated with or into
         the Borrower or a Restricted Subsidiary, or (iii) prior to the
         acquisition thereof by the Borrower or any Restricted Subsidiary,
         PROVIDED that, in any such case, (A) such Lien (1) was not created in
         contemplation of such event and (2) is not extended to other property,
         and (B) the amount of Debt secured by any such Lien does not exceed the
         lesser of (x) the cost to the Borrower or Restricted Subsidiary
         (including the principal amount of any pre-existing Debt secured by
         such Lien, whether or not the Borrower or such Restricted Subsidiary
         has any personal liability with respect thereto) of such asset and (y)
         the fair market value of such asset (as determined in good faith by the
         chief financial officer of the Borrower or Restricted Subsidiary) at
         the time of acquisition thereof;

                  (i) Liens extending, renewing or replacing any Lien permitted
         by clause (f), (g) or (h) of this section, PROVIDED that such Liens are
         not extended to other property; and

                  (j) Liens in addition to those permitted by the foregoing
         clauses (a) through (i) of this section incurred after the date hereof
         if, immediately after giving effect to the incurrence of such
         additional Lien, Priority Debt does not exceed the lesser of $5,000,000
         and 15% of Total Capitalization.

         SECTION 5.13. CURRENT RATIO. The Borrower will maintain at all times
(i) from January 1 through June 30 of each year a ratio of Consolidated Current
Assets to Consolidated Current Liabilities of at least 1.00 to 1.00, and (ii)
from July 1 through December 31 of each year a ratio of Consolidated Current
Assets to Consolidated Current Liabilities of at least 1.50 to 1.00.

         SECTION 5.14. RATIO OF CONSOLIDATED LIABILITIES TO CONSOLIDATED
TANGIBLE NET WORTH. The Borrower will not permit the ratio of Consolidated
Liabilities (exclusive of liabilities for accrued post-retirement health benefit
expenses) to Consolidated Tangible Net Worth to be greater than 3.00 to 1.00 at
any time.

         SECTION 5.15. INTEREST COVERAGE RATIO. The Borrower will maintain an
Interest Coverage Ratio greater than 3.00 to 1.00.

         SECTION 5.16. CERTAIN SUBSIDIARIES TO GUARANTEE ADVANCES. In the event
any Restricted Subsidiary of the Borrower has at any time assets with a net book
value, or fair market value, whichever is greater, in excess of $5,000,000, the
Borrower will, within 30 days following request therefor from the Agent or any
Bank, cause such Restricted Subsidiary to deliver to the Agent, in sufficient
quantities for the Banks, (i) a guaranty, satisfactory in form and substance to
the Agent and the Majority Banks, duly executed by such Subsidiary,
substantially in the form attached hereto as Exhibit E, pursuant to which such
Restricted Subsidiary unconditionally and absolutely guarantees payment of all
Advances made hereunder, and (ii) resolutions of the Board of Directors of such
Restricted Subsidiary, certified by the Secretary or an Assistant Secretary of
such Restricted Subsidiary as duly adopted and in full force and effect,
authorizing the execution and delivery of such


                                       28


<PAGE>   33

guaranty. In the event that any Restricted Subsidiary at any time has assets
which meet or exceed the foregoing value requirement, the Borrower will
promptly, and in any event within 30 days following the occurrence of such
event, notify the Agent in writing of such event, identifying the Restricted
Subsidiary in question and referring specifically to the rights of the Agent and
the Banks under this section.

         SECTION 5.17. INVESTMENTS, ACQUISITIONS, ETC. The Borrower will not,
and will not permit any of its Restricted Subsidiaries to, at any time after the
Restatement Effective Date, (i) make any loan or advance to any Person (other
than loans to officers, directors and employees or prospective employees in the
ordinary course of business in an aggregate amount for the Borrower and its
Restricted Subsidiaries not in excess of $500,000 at any one time outstanding),
(ii) purchase or otherwise acquire any stock, obligations or securities of, or
any other interest in, or make any capital contribution to, any other Person, or
acquire from any Person any division, plant or other business unit, or (iii) be
or become a general partner (or the equivalent) in any Person, other than:

                  (a)      investments in Cash Equivalents;

                  (b) if no Default or Event of Default has occurred and is
         continuing or would result therefrom, (i) purchases or other
         acquisitions of stock, obligations or securities of, any other Person
         which, as a result thereof, becomes a Wholly-owned Subsidiary, and (ii)
         acquisitions from any other Person of any division, plant or other
         business unit, in each case specified in the foregoing clauses (i) and
         (ii) in a negotiated transaction not involving a line of business or
         business activities not permitted by section 5.05;

                  (c) loans, advances and other investments in the Borrower's
         existing Wholly-owned Restricted Subsidiaries, and loans, advances and
         other investments in Persons which become Wholly-owned Restricted
         Subsidiaries in transactions referred to in the foregoing clause (b) or
         in transactions referred to in clause (ii) of section 5.08(a);

                  (d) loans, advances and other investments by Restricted
         Subsidiaries in the Borrower;

                  (e) loans, advances and investments in Unrestricted
         Subsidiaries in an aggregate amount which, after giving effect thereto,
         are not in excess of 10% of the Borrower's Consolidated Tangible Net
         Worth; and

                  (f) other loans, advances and investments made after the
         Restatement Effective Date, not otherwise permitted by the foregoing
         clauses of this section, in an aggregate amount not in excess of
         $1,000,000.


                                   ARTICLE VI

                                EVENTS OF DEFAULT

         SECTION 6.01. EVENTS OF DEFAULT. If any of the following events
("EVENTS OF DEFAULT") shall occur and be continuing:

                  (a) default shall be made in the due and punctual payment of
         all or any part of the principal of any Note when and as the same shall
         become due and payable, whether on a date fixed for a prepayment, at
         stated maturity, by acceleration or declaration, or otherwise; or

                  (b) default shall be made in the payment of any interest on
         any Note when and as such interest shall become due and payable, and
         such default shall have continued for a period of five days; or

                                       29
<PAGE>   34

                  (c) default shall be made in the payment of any commitment fee
         or other amount not specified in clause (a) or (b) above payable by the
         Borrower hereunder as and when such fee or other amount shall become
         due and payable, and such default shall continue for a period of five
         days; or

                  (d) default shall be made in the performance or observance of
         any other covenant, agreement or condition contained in this Agreement
         and such default shall have continued for a period of 30 days after any
         officer of the Borrower shall become aware of the default or of the
         conditions or events giving rise to such default; or

                  (e) default shall be made in the payment of any part of the
         principal or the premium (if any) or the interest on, or any other
         payment of, money due under any Debt of the Borrower or any Restricted
         Subsidiary (other than the Notes) aggregating more than $10,000,000,
         beyond any period of grace provided with respect thereto, or default
         shall be made in the performance or observance of any other covenant,
         agreement or condition contained in any indenture, credit agreement or
         loan agreement or other agreement or instrument under which Debt of the
         Borrower or any Restricted Subsidiary is evidenced, for a period of
         time sufficient to permit the holder or holders of any such Debt (or
         trustee or agent on its or their behalf) to accelerate the maturity
         thereof or to enforce any lien provided for by any such indenture,
         agreement or instrument, as the case may be; or

                  (f) the Borrower or any Restricted Subsidiary shall (i) apply
         for or consent to the appointment of, or the taking of possession by, a
         receiver, custodian, trustee or liquidator of itself or of all or a
         substantial part of its property, (ii) be generally unable or admit in
         writing its inability to pay its debts as such debts become due, (iii)
         make a general assignment for the benefit of its creditors, (iv)
         commence a voluntary case under the Federal Bankruptcy Code (as now or
         hereafter in effect), (v) file a petition seeking to take advantage of
         any bankruptcy, insolvency, moratorium, reorganization or other similar
         law affecting the enforcement of creditors' rights generally, (vi)
         acquiesce in writing to, or fail to controvert in a timely or
         appropriate manner, any petition filed against it in an involuntary
         case under such Bankruptcy Code, (vii) take any action under the laws
         of any jurisdiction analogous to any of the foregoing, or (viii) take
         any corporate action in furtherance of any of the foregoing; or

                  (g) a proceeding or case shall be commenced, without the
         application or consent of the Borrower or any Restricted Subsidiary, in
         any court of competent jurisdiction, seeking (i) the liquidation,
         reorganization, moratorium, dissolution, winding up, or composition or
         readjustment of its debts, (ii) the appointment of a trustee, receiver,
         custodian, liquidator or the like of it or of all or any substantial
         part of its assets, or (iii) similar relief in respect of it under any
         law providing for the relief of debtors, and such proceeding or case
         described in clause (i), (ii), or (iii) shall continue undismissed, or
         unstayed and in effect, for a period of 60 days; or

                  (h) final judgment or judgments for the payment of money in
         excess of $1,000,000 (net of insurance coverage as to which the carrier
         shall have acknowledged responsibility) for any one or in the aggregate
         shall be rendered by a court of competent jurisdiction against the
         Borrower or any Restricted Subsidiary and the Borrower or such
         Restricted Subsidiary, as the case may be, shall not discharge the same
         or provide for its discharge in accordance with its terms, or procure a
         stay of execution thereof within 60 days from the date of entry thereof
         and within said period of 60 days, or such longer period during which
         execution or such judgment shall have been stayed, or appeal therefrom
         and cause the execution thereof to be stayed during such appeal; or

                  (i) any representation or warranty made by the Borrower in
         this Agreement or in any certificate or other instrument delivered
         hereunder or pursuant thereto or in connection with any provision
         thereof shall prove to have been false or incorrect or breached in any
         material respect on the date as of which made; or

                  (j) (i) any Company Group Member shall fail to pay when due
         any amount which it shall have become liable to pay to the PBGC or to a
         Plan under Title IV of ERISA; (ii) any Company Group

                                       30
<PAGE>   35



         Member shall withdraw from a Multiple Employer Plan during a plan year
         in which it is a substantial employer (as such term is defined in
         section 4001(a)(2) of ERISA), or shall incur any liability under
         section 4064 or 4062(a)of ERISA; (iii) notice of intent to terminate a
         Plan or Plans shall be filed under Title IV of ERISA by an Company
         Group Member, any plan administrator or any combination of the
         foregoing; (iv) the PBGC shall institute proceedings under Title IV of
         ERISA to terminate or to cause a trustee to be appointed to administer
         any Plan or Plans; (v) any Company Group Member shall incur any
         withdrawal liability with respect to any Multiemployer Plan; (vi) any
         Plan other than a Multiemployer Plan shall have an Unfunded Current
         Liability; or (vii) any Company Group Member shall engage in any
         "prohibited transaction" (as defined in section 406 of ERISA or section
         4975 of the Code) or any breach of any fiduciary responsibility
         (under Part 4 of Title I of ERISA) which may subject such Company Group
         Member to any liability for a civil penalty or a tax pursuant to
         section 409 or 502(i) or (1) of ERISA, or section 4975 of the Code,
         respectively; and there shall result from any such event or events
         described in clauses (i) through (vii) above a reasonable risk of
         incurring a material liability on the part of any Company Group Member;
         or

                  (k)      any Change in Control shall have occurred;

then, and in any such event, the Agent (i) shall at the request, or may with the
consent, of the holders of at least 50% in principal amount of the Notes then
outstanding or, if no Notes are then outstanding, Banks having at least 50% of
the Commitments, by notice to the Borrower, declare the obligation of each Bank
to make Advances to be terminated, whereupon the same shall forthwith terminate,
and (ii) shall at the request, or may with the consent, of the holders of at
least 50% in principal amount of the Notes then outstanding or, if no Notes are
then outstanding, Banks having at least 50% of the Commitments, by notice to the
Borrower, declare the Notes, all interest thereon and all other amounts payable
under this Agreement to be forthwith due and payable, whereupon the Notes, all
such interest and all such amounts shall become and be forthwith due and
payable, without presentment, demand, protest or further notice of any kind, all
of which are hereby expressly waived by the Borrower; PROVIDED, HOWEVER, that in
the event of an actual or deemed entry of an order for relief with respect to
the Borrower or any of its Restricted Subsidiaries under the Federal Bankruptcy
Code, (A) the obligation of each Bank to make Advances shall automatically be
terminated and (B) the Notes, all such interest and all such amounts shall
automatically become and be due and payable, without presentment, demand,
protest or any notice of any kind, all of which are hereby expressly waived by
the Borrower.


                                   ARTICLE VII

                                    THE AGENT

         SECTION 7.01. AUTHORIZATION AND ACTION. Each Bank hereby appoints and
authorizes the Agent to take such action as agent on its behalf and to exercise
such powers under this Agreement as are delegated to the Agent by the terms
hereof, together with such powers as are reasonably incidental thereto. As to
any matters not expressly provided for by this Agreement (including, without
limitation, enforcement or collection of the Notes), the Agent shall not be
required to exercise any discretion or take any action, but shall be required to
act or to refrain from acting (and shall be fully protected in so acting or
refraining from acting) upon the instructions of holders of at least 75% in
principal amount of the Notes then outstanding (or if no Notes are at the time
outstanding, upon the instructions of Banks having at least 75% of the
Commitments), and such instructions shall be binding upon all Banks and all
holders of Notes; PROVIDED, HOWEVER, that the Agent shall not be required to
take any action which exposes the Agent to personal liability or which is
contrary to this Agreement or applicable law. The Agent agrees to give to each
Bank prompt notice of each notice given to it by the Borrower pursuant to the
terms of this Agreement.

         SECTION 7.02. AGENT'S RELIANCE, ETC. Neither the Agent nor any of its
directors, officers, agents or employees shall be liable for any action taken or
omitted to be taken by it or them under or in connection with this Agreement,
except for its or their own gross negligence or willful misconduct. Without
limitation of the generality of the foregoing, the Agent: (i) may treat the
payee of any Note as the holder thereof until the Agent




                                       31

<PAGE>   36



receives written notice of the assignment or transfer thereof signed by such
payee and including the agreement of the assignee or transferee to be bound
hereby as it would have been if it had been an original Bank party hereto, in
form satisfactory to the Agent; (ii) may consult with legal counsel (including
counsel for the Borrower), independent public accountants and other experts
selected by it and shall not be liable for any action taken or omitted to be
taken in good faith by it in accordance with the advice of such counsel,
accountants or experts; (iii) makes no warranty or representation to any Bank
and shall not be responsible to any Bank for any statements, warranties or
representations (whether written or oral) made in or in connection with this
Agreement; (iv) shall not have any duty to ascertain or to inquire as to the
performance or observance of any of the terms, covenants or conditions of this
Agreement on the part of the Borrower or to inspect the property (including the
books and records) of the Borrower; (v) shall not be responsible to any Bank for
the due execution, legality, validity, enforceability, genuineness, sufficiency
or value of this Agreement or any other instrument or document furnished
pursuant hereto; and (vi) shall incur no liability under or in respect of this
Agreement by acting upon any notice, consent, certificate or other instrument or
writing (which may be by telecopier, telegram, cable or telex) believed by it to
be genuine and signed or sent by the proper party or parties.

         SECTION 7.03. SOCIETY AND AFFILIATES. With respect to its Commitment,
the Advances made by it and the Note issued to it, Society shall have the same
rights and powers under this Agreement as any other Bank and may exercise the
same as though it were not the Agent; and the term "BANK" or "BANKS" shall,
unless otherwise expressly indicated, include Society in its individual
capacity. Society and its Affiliates may accept deposits from, lend money to,
act as trustee under indentures of, and generally engage in any kind of business
with, the Borrower, any of its subsidiaries and any Person who may do business
with or own securities of the Borrower or any such subsidiary, all as if Society
were not the Agent and without any duty to account therefor to the Banks.

         SECTION 7.04. BANK CREDIT DECISION. Each Bank acknowledges that it has,
independently and without reliance upon the Agent or any other Bank and based on
the financial statements referred to in section 4.01 and such other documents
and information as it has deemed appropriate, made its own credit analysis and
decision to enter into this Agreement. Each Bank also acknowledges that it will,
independently and without reliance upon the Agent or any other Bank and based on
such documents and information as it shall deem appropriate at the time,
continue to make its own credit decisions in taking or not taking action under
this Agreement.

         SECTION 7.05. INDEMNIFICATION. The Banks agree to indemnify the Agent
(to the extent not reimbursed by the Borrower), ratably according to the
respective principal amounts of the Notes then held by each of them (or if no
Notes are at the time outstanding or if any Notes are held by Persons which are
not Banks, ratably according to the respective amounts of their Commitments),
from and against any and all liabilities, obligations, losses, damages,
penalties, actions, judgments, suits, costs, expenses or disbursements of any
kind or nature whatsoever which may be imposed on, incurred by, or asserted
against the Agent in any way relating to or arising out of this Agreement or any
action taken or omitted by the Agent under this Agreement, PROVIDED that no Bank
shall be liable for any portion of such liabilities, obligations, losses,
damages, penalties, actions, judgments, suits, costs, expenses or disbursements
resulting from the Agent's gross negligence or willful misconduct. Without
limitation of the foregoing, each Bank agrees to reimburse the Agent promptly
upon demand for its ratable share of any out-of-pocket expenses (including
counsel fees) incurred by the Agent in connection with the preparation,
execution, delivery, administration, modification, amendment or enforcement
(whether through negotiations, legal proceedings or otherwise) of, or legal
advice in respect of rights or responsibilities under, this Agreement, to the
extent that the Agent is not reimbursed for such expenses by the Borrower.

         SECTION 7.06. SUCCESSOR AGENT. The Agent may resign at any time by
giving written notice thereof to the Banks and the Borrower and may be removed
at any time with or without cause by the Majority Banks. Upon any such
resignation or removal, the Majority Banks shall have the right to appoint a
successor Agent. If no successor Agent shall have been so appointed by the
Majority Banks, and shall have accepted such appointment, within 30 days after
the retiring Agent's giving of notice of resignation or the Majority Banks'
removal of the retiring Agent, then the retiring Agent may, on behalf of the
Banks, appoint a successor Agent,

                                       32

<PAGE>   37


which shall be a commercial bank organized under the laws of the United States
of America or of any State thereof and having a combined capital and surplus of
at least $50,000,000. Upon the acceptance of any appointment as Agent hereunder
by a successor Agent, such successor Agent shall thereupon succeed to and become
vested with all the rights, powers, privileges and duties of the retiring Agent,
and the retiring Agent shall be discharged from its duties and obligations under
this Agreement. After any retiring Agent's resignation or removal hereunder as
Agent, the provisions of this Article VII shall inure to its benefit as to any
actions taken or omitted to be taken by it while it was Agent under this
Agreement.


                                  ARTICLE VIII

                                  MISCELLANEOUS

         SECTION 8.01. AMENDMENTS, ETC. No amendment or waiver of any provision
of this Agreement or the Notes, nor consent to any departure by the Borrower
therefrom, shall in any event be effective unless the same shall be in writing
and signed by the Majority Banks, and then such waiver or consent shall be
effective only in the specific instance and for the specific purpose for which
given; PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in
writing and signed by all the Banks, do any of the following: (a) waive any of
the conditions specified in Article III, (b) increase the Commitments of the
Banks or subject the Banks to any additional obligations, (c) reduce the
principal of, or interest on, the Notes or any fees or other amounts payable
hereunder (including, without limitation, any such reduction effected by means
of any amendment to the definition of the term Applicable Increment or any of
the other terms defined herein), (d) postpone any date fixed for any payment of
principal of, or interest on, the Notes or any fees or other amounts payable
hereunder, (e) change the percentage of the Commitments or of the aggregate
unpaid principal amount of the Notes, or the number of Banks, which shall be
required for the Banks or any of them to take any action hereunder or (f) amend
this section 8.01; and PROVIDED, FURTHER, that no amendment, waiver or consent
shall, unless in writing and signed by the Agent in addition to the Banks
required above to take such action, affect the rights or duties of the Agent
under this Agreement or any Note.

         SECTION 8.02. NOTICES, ETC. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered, if to the Borrower, at its address at 3008 Monticello
Boulevard, Cleveland Heights, Ohio 44118, Attention: Chairman of the Board or
President; if to any Bank, at its Domestic Lending Office specified opposite its
name on Schedule I hereto; and if to the Agent, at its address at 127 Public
Square, Cleveland, Ohio 44114-1306, Attention: Commercial Banking
Department-Large Corporate Group, as to the Borrower or the Agent, at such other
address as shall be designated by such party in a written notice to the other
parties and, as to each other party, at such other address as shall be
designated by such party in a written notice to the Borrower and the Agent. All
such notices and communications shall, when mailed, telecopied, telegraphed,
telexed or cabled, be effective when deposited in the mails, telecopied,
delivered to the telegraph company, confirmed by telex answerback or delivered
to the cable company, respectively, except that notices and communications to
the Agent pursuant to Article II or VII shall not be effective until received by
the Agent.

         SECTION 8.03. NO WAIVER; REMEDIES. No failure on the part of any Bank
or the Agent to exercise, and no delay in exercising, any right under this
Agreement or any Note shall operate as a waiver thereof; nor shall any single or
partial exercise of any such right preclude any other or further exercise
thereof or the exercise of any other right. The remedies herein provided are
cumulative and not exclusive of any remedies provided by law.

         SECTION 8.04. COSTS, EXPENSES AND TAXES. (a) The Borrower agrees to pay
on demand all costs and expenses in connection with the preparation, execution,
delivery, administration, modification and amendment of this Agreement and the
other documents to be delivered hereunder, including, without limitation, the
reasonable fees and out-of-pocket expenses of counsel for the Agent with respect
thereto and with respect to advising the Agent as to its rights and
responsibilities under this Agreement. The Borrower further agrees to pay on
demand all costs and expenses, if any (including, without limitation, reasonable
counsel fees and 

                                       33

<PAGE>   38



expenses), of the Banks and the Agent in connection with the enforcement
(whether through negotiations, legal proceedings or otherwise) of this Agreement
and the other documents to be delivered hereunder, including, without
limitation, reasonable counsel fees and expenses in connection with the
enforcement of rights under this section 8.04(a). In addition, the Borrower
shall pay any and all stamp and other similar taxes payable or determined to be
payable in connection with the execution and delivery of this Agreement and the
Notes and the other documents to be delivered hereunder, and agrees to save the
Agent and each Bank harmless from and against any and all liabilities with
respect to or resulting from any delay in paying or omission to pay such taxes.

         (b) If any payment of principal of, or Conversion of, any Eurodollar
Rate Advance is made other than on the last day of an Interest Period relating
to such Advance, as a result of a payment or Conversion pursuant to section 2.10
or 2.08(d) or acceleration of the maturity of the Notes pursuant to section 6.01
or for any other reason, the Borrower shall, upon demand by any Bank (with a
copy of such demand to the Agent), pay to the Agent for the account of such Bank
any amounts required to compensate such Bank for any additional losses, costs or
expenses which it may reasonably incur as a result of such payment or
Conversion, including, without limitation, any loss (including loss of
anticipated profits), cost or expense incurred by reason of the liquidation or
reemployment of deposits or other funds acquired by such Bank to fund or
maintain such Advance.

       SECTION 8.05. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 to authorize the Agent to
declare the Notes due and payable pursuant to the provisions of section 6.01,
each Bank is hereby authorized at any time and from time to time, to the fullest
extent permitted by law, to set off and apply any and all deposits (general or
special, time or demand, provisional or final) at any time held and other
indebtedness at any time owing by such Bank to or for the credit or the account
of the Borrower against any and all of the obligations of the Borrower now or
hereafter existing under this Agreement or the Notes, whether or not such Bank
shall have made any demand under this Agreement or such Note and although such
obligations may be unmatured. Each Bank agrees promptly to notify the Borrower
after any such set-off and application made by such Bank, PROVIDED that the
failure to give such notice shall not affect the validity of such set-off and
application. The rights of each Bank under this section are in addition to other
rights and remedies (including, without limitation, other rights of set-off)
which such Bank may have.

         SECTION 8.06. BINDING EFFECT. This Agreement shall become effective
when (i) it shall have been executed by the Borrower and the Agent, (ii) the
conditions specified in section 3.01 shall have been satisfied, and (iii) the
Agent shall have been notified by each Bank that such Bank has executed this
Agreement, and thereafter this Agreement shall be binding upon and inure to the
benefit of the Borrower, the Agent and each Bank and their respective successors
and assigns, except that the Borrower shall not have the right to assign its
rights hereunder or any interest herein without the prior written consent of the
Banks.

         SECTION 8.07. ASSIGNMENTS AND PARTICIPATIONS. (a) Each Bank may assign
to one or more Banks or other entities all or a portion of its rights and
obligations under this Agreement (including, without limitation, all or a
portion of its Commitment and the Advances owing to it); PROVIDED, HOWEVER, that
(A) each such assignment shall be of a uniform, and not a varying, percentage of
all rights and obligations under and in respect of all of such Bank's
Commitment, (B) except in the case of an assignment to a Bank, the amount of the
Commitment of the assigning Bank being assigned pursuant to each such assignment
(determined as of the date of the Assignment and Acceptance with respect to such
assignment) shall in no event be less than $5,000,000 and shall (unless such
amount constitutes the entire remaining amount of the assigning Bank's
Commitment) be an integral multiple of $1,000,000, (C) each such assignment
shall be to an Eligible Assignee, and (D) the parties to each such assignment
shall execute and deliver to the Agent, for its acceptance and recording, an
Assignment and Acceptance (the "ASSIGNMENT AND ACCEPTANCE") in substantially the
form attached hereto as Exhibit D, together with a processing and recordation
fee of $2,000. Upon such execution, delivery, acceptance and recording, from and
after the effective date specified in such Assignment and Acceptance, (x) the
assignee thereunder shall be a party hereto and, to the extent that rights and
obligations hereunder have been assigned to it pursuant to such Assignment and
Acceptance, have the rights and obligations of a Bank hereunder and (y) the Bank
assignor thereunder shall, to the extent that rights and obligations hereunder
have been assigned by it pursuant to such Assignment and Acceptance, relinquish
its rights and be released from its obligations under

                                       34

<PAGE>   39

this Agreement (and, in the case of an Assignment and Acceptance covering all or
the remaining portion of an assigning Bank's rights and obligations under this
Agreement, such Bank shall cease to be a party hereto).

         (b) By executing and delivering an Assignment and Acceptance, the Bank
assignor thereunder and the assignee thereunder confirm to and agree with each
other and the other parties hereto as follows: (i) other than as provided in
such Assignment and Acceptance, such assigning Bank makes no representation or
warranty and assumes no responsibility with respect to any statements,
warranties or representations made in or in connection with this Agreement or
the execution, legality, validity, enforceability, genuineness, sufficiency or
value of this Agreement or any other instrument or document furnished pursuant
hereto; (ii) such assigning Bank makes no representation or warranty and assumes
no responsibility with respect to the financial condition of the Borrower or the
performance by the Borrower of any of its obligations under this Agreement or
any other instrument or document furnished pursuant hereto; (iii) such assignee
confirms that it has received a copy of this Agreement, together with copies of
the financial statements referred to in section 4.01(d) and such other documents
and information as it has deemed appropriate to make its own credit analysis and
decision to enter into such Assignment and Acceptance; (iv) such assignee will,
independently and without reliance upon the Agent, such assigning Bank or any
other Bank and based on such documents and information as it shall deem
appropriate at the time, continue to make its own credit decisions in taking or
not taking action under this Agreement; (v) such assignee confirms that it is an
Eligible Assignee; (vi) such assignee appoints and authorizes the Agent to take
such action as agent on its behalf and to exercise such powers and discretion
under this Agreement as are delegated to the Agent by the terms hereof, together
with such powers and discretion as are reasonably incidental thereto; and (vii)
such assignee agrees that it will perform in accordance with their terms all of
the obligations that by the terms of this Agreement are required to be performed
by it as a Bank.

         (c) The Agent shall maintain at its address referred to in section 8.02
a copy of each Assignment and Acceptance delivered to and accepted by it and a
register for the recordation of the names and addresses of the Banks and the
Commitment of, and principal amount of the Advances owing to, each Bank from
time to time (the "REGISTER"). The entries in the Register shall be conclusive
and binding for all purposes, absent manifest error, and the Borrower, the Agent
and the Banks may treat each person whose name is recorded in the Register as a
Bank hereunder for all purposes of this Agreement. The Register shall be
available for inspection by the Borrower or any Bank at any reasonable time and
from time to time upon reasonable prior notice.

         (d) Upon its receipt of an Assignment and Acceptance executed by an
assigning Bank and an assignee representing that it is an Eligible Assignee, the
Agent shall, if such Assignment and Acceptance has been completed and is in form
acceptable to the Agent, (i) accept such Assignment and Acceptance, (ii) record
the information contained therein in the Register and (iii) give prompt notice
thereof to the Borrower.

         (e) Each Bank may sell participations to one or more Banks or other
entities in or to all or a portion of its rights and obligations under this
Agreement (including, without limitation, all or a portion of its Commitment and
the Advances owing to it); PROVIDED, HOWEVER, that (i) such Bank's obligations
under this Agreement (including, without limitation, its Commitment to the
Borrower hereunder) shall remain unchanged, (ii) such Bank shall remain solely
responsible to the other parties hereto for the performance of such obligations,
(iii) the Borrower, the Agent and the other Banks shall continue to deal solely
and directly with such Bank in connection with such Bank's rights and
obligations under this Agreement, and (iv) no participant under any such
participation shall have any right to approve any amendment or waiver of any
provision of this Agreement, or any consent to any departure by Borrower
therefrom, except to the extent that such amendment, waiver or consent would
reduce the principal of, or interest on, the Advances or any fees or other
amounts payable hereunder, in each case to the extent subject to such
participation, postpone any date fixed for any payment of principal of, or
interest on, the Advances or any fees or other amounts payable hereunder, in
each case to the extent subject to such participation.

         (f) Any Bank may, in connection with any assignment or participation or
proposed assignment or participation pursuant to this section, disclose to the
assignee or participant or proposed assignee or participant, any information
relating to the Borrower furnished to such Bank by or on behalf of the Borrower;
PROVIDED,


                                       35

<PAGE>   40





HOWEVER, that, prior to any such disclosure, the assignee or participant or
proposed assignee or participant shall agree to preserve the confidentiality of
any confidential information received by it from such Bank.

         SECTION 8.08. GOVERNING LAW. This Agreement and the Notes shall be
governed by, and construed in accordance with, the laws of the State of Ohio.

         SECTION 8.09. EXECUTION IN COUNTERPARTS. This Agreement may be executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed to be an original
and all of which taken together shall constitute one and the same agreement.

         SECTION 8.10. INDEMNIFICATION. The Borrower hereby indemnifies and
holds the Agent and each Bank harmless from and against any and all claims,
damages, losses, liabilities, costs or expenses which the Agent or such Bank may
incur or which may be claimed against the Agent or such Bank by any person or
entity:

                  (a) by reason of any proposed or actual use of the proceeds of
         any Borrowing;

                  (b) by reason of or in connection with the execution, delivery
         or performance of this Agreement or any transaction contemplated
         hereby; PROVIDED, HOWEVER, that the Borrower shall not be required to
         indemnify the Agent or such Bank pursuant to this section 8.10(b) for
         any claims, damages, losses, liabilities, costs or expenses to the
         extent caused by the Agent's or such Bank's wilful misconduct or gross
         negligence; or

                  (c) by reason of or in connection with any liability or
         alleged liability which arises under any Environmental Law and which
         occurs upon or from any real property owned, operated, or leased by the
         Borrower or any Subsidiary either as of the date of this Agreement or
         at any time thereafter, or any fixture or personal property used in
         connection therewith, and the Borrower's rights to leases, rents and
         profits with respect thereto, or by the reason of any governmental
         response costs pursuant to any Environmental Law.

         Nothing in this section is intended to limit the Borrower's obligations
contained in Article II. Without prejudice to the survival of any other
obligation of the Borrower hereunder, the indemnities and obligations of the
Borrower contained in this section shall survive the payment in full of amounts
payable pursuant to Article II.

         SECTION 8.11. NO MARGIN STOCK COLLATERAL. Each of the Banks represents
to the Agent and each of the other Banks that it in good faith is not, directly
or indirectly (by negative pledge or otherwise) relying upon any margin stock
(as defined in Regulation U of the Board of Governors of the Federal Reserve
System) as collateral in the extension or maintenance of the credit provided for
in this Agreement.

         SECTION 8.12. JURY TRIAL WAIVER. THE BORROWER AND THE AGENT AND EACH
LENDER EACH WAIVE ANY RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE,
WHETHER SOUNDING IN CONTRACT, TORT OR OTHERWISE, BETWEEN THE AGENT OR ANY LENDER
AND THE BORROWER ARISING OUT OF, IN CONNECTION WITH, RELATED TO, OR INCIDENTAL
TO THE RELATIONSHIP ESTABLISHED BETWEEN THEM IN CONNECTION WITH THIS AGREEMENT
OR ANY NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS RELATED THERETO.



               [The balance of this page is intentionally blank.]




                                       36

<PAGE>   41




         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their respective officers thereunto duly authorized, as of the date
first above written.



                                       MEDUSA CORPORATION


                                       BY: /s/ R. Breck Denny
                                           ------------------------------
                                           TITLE: VICE PRESIDENT-FINANCE



                                       SOCIETY NATIONAL BANK, AS AGENT


                                       BY: /s/ Thomas J. Purcell
                                           -------------------------------
                                           TITLE: ASST. VICE PRESIDENT






                    [Signatures continued on following page.]





                                       37

<PAGE>   42





                                           BANKS

COMMITMENT
$17,500,000                             SOCIETY NATIONAL BANK
(39%)


                                        By: /s/ Thomas J. Purcell
                                            ----------------------------------
                                            Title: Asst. Vice President



$10,000,000                             NBD BANK
(22%)


                                        By: /s/ Illegible
                                            ----------------------------------
                                            Title: Vice President



$10,000,000                             NATIONAL CITY BANK
(22%)

                                        By: /s/ Illegible
                                            ----------------------------------
                                            Title: Vice President



$7,500,000                              PNC BANK, NATIONAL ASSOCIATION
(17%)

                                        By: /s/ Illegible
                                            ----------------------------------
                                            Title: Asst. Vice President



Total of Commitments:

$45,000,000
(100%)





                                       38

<PAGE>   43


<TABLE>
<CAPTION>


                                                    SCHEDULE I

                                                MEDUSA CORPORATION

                                            REVOLVING CREDIT AGREEMENT

-------------------------------------------------------------------------------------------------------------------------------
                                                  DOMESTIC LENDING                       EURODOLLAR LENDING
             NAME OF BANK                           OFFICE                                  OFFICE
--------------------------------------------------------------------------------------------------------------------------------
<S>                                     <C>                                      <C>
Society National Bank                   Society Center                          Same as Domestic Lending Office
                                        Mailcode OH-01-27-0606
                                        127 Public Square
                                        Cleveland, Ohio  44114-1306
                                        Attention: Large Corporate Group
                                                   Thomas J. Purcell
                                                   Assistant Vice President
                                        Telephone: (216) 689-4439
                                        Facsimile:  (216) 689-4981

                                        CONTACT FOR BORROWINGS, PAYMENTS, ETC.:

                                        Cathy Sledge

                                        Telephone: (216) 689-4450
                                        Facsimile: (216) 689-4981

                                        ABA # 041001039
--------------------------------------------------------------------------------------------------------------------------------
NBD Bank                                NBD Bank                                Same as Domestic Lending Office
                                        611 Woodward Avenue
                                        Detroit, Michigan 48226


                                        CONTACTS/NOTIFICATION METHODS:

                                        NBD Bank
                                        611 Woodward Avenue
                                        Detroit, Michigan 48226
                                             Andrew W. Strait
                                             Vice President
                                             Midwest Banking Division

                                        Telephone: (313) 225-3300
                                        Telecopy:  (313) 225-1671



                                        CONTACT FOR BORROWINGS, PAYMENTS, ETC.:

                                        Patti Deuweke
                                        Telephone: (313) 225-1274
                                        Telecopy:  (313) 225-1671

                                        ABA # 0720 003 26

--------------------------------------------------------------------------------------------------------------------------------
</TABLE>






<PAGE>   44

<TABLE>
<CAPTION>

--------------------------------------------------------------------------------------------------------------------------------
                                              DOMESTIC LENDING                       EURODOLLAR LENDING
             NAME OF BANK                          OFFICE                                  OFFICE
--------------------------------------------------------------------------------------------------------------------------------
<S>                                     <C>                                      <C>
National City Bank                      National City Bank                      Same as Domestic Lending Office
                                        1900 East Ninth Street
                                        Cleveland, Ohio 44114

                                        PRIMARY CONTACT:

                                        National City Bank
                                        1900 East Ninth Street
                                        Cleveland, Ohio 44114
                                        Attention:
                                          Christopher M. Karr
                                          Vice President
                                        Metro Ohio Division

                                        Telephone: (216) 575-2000
                                        Telecopy:  (216) 575-9396
                                        Telex:     980394

                                        FOR WIRING:

                                        National City Center
                                        1900 East Ninth Street
                                        Cleveland, Ohio 44114
                                        Attention: Revette Flanigan
                                          Commercial Loan Operations

                                        Telephone: (216) 575-3276
                                        Telecopy:  (216) 575-3207

                                        ABA # 041000124
--------------------------------------------------------------------------------------------------------------------------------
</TABLE>





                                        2

<PAGE>   45

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------------------
                                                   DOMESTIC LENDING                       EURODOLLAR LENDING
             NAME OF BANK                               OFFICE                                  OFFICE
--------------------------------------------------------------------------------------------------------------------------------
<S>                                     <C>                                     <C>
PNC Bank, National Association          PNC Bank, National Association          Same as Domestic Lending Office
                                        One PNC Plaza
                                        Fifth and Wood Streets
                                        Pittsburgh, Pennsylvania 15265

                                        CONTACTS/NOTIFICATION METHODS:


                                        PNC Bank, National Association
                                        Suite 1250
                                        1375 East Ninth Street
                                        Cleveland, Ohio 44114-3103

                                        Joseph G. Moran
                                        Vice President
                                        Telephone: (216) 348-8560
                                        Facsimile: (216) 348-8594

                                        Chris Helmeci
                                        Relationship Manager
                                        Telephone: (216) 348-8580
                                        Facsimile: (216) 348-8594

                                        CONTACT FOR BORROWINGS, PAYMENTS, ETC.:


                                        PNC Bank, National Association
                                        Suite 1250
                                        1375 East Ninth Street
                                        Cleveland, Ohio 44114-3103

                                        Attention: Denise T. Gottlieb
                                        Telephone: (216) 348-8552
                                        Facsimile: (216) 348-8594

                                        ABA # 043000096

--------------------------------------------------------------------------------------------------------------------------------
</TABLE>










                                        3

<PAGE>   46





                                   SCHEDULE II


                            CERTAIN ERISA DISCLOSURES
<TABLE>
<CAPTION>



--------------------------------------------------------------------------------------------------------------------------------
PLAN                   Incurrence Date       Explanation                     Liability           Source of Funds        Status
--------------------------------------------------------------------------------------------------------------------------------
<S>                    <C>                   <C>                            <C>                  <C>                    <C>    
Central States,        December 10,          Multiemployer                   $355,000            $200,000 paid by       Paid in
Southeast and          1982                  withdrawal liability                                Travelers              Full
Southwest Areas                              incurred by reason of the                           Insurance;
Pension Fund,                                sale of substantially all of                        balance from the
Chicago, Illinois                            the assets of New Hudson                            Company
                                             and Walker Sand and
                                             Gravel operations by
                                             Medusa Aggregates
                                             Company to Milford Sand
                                             and Gravel Company
--------------------------------------------------------------------------------------------------------------------------------
</TABLE>











<PAGE>   47



                                  SCHEDULE III


                                OUTSTANDING DEBT


         1.       Short term Debt outstanding under lines of credit.

         2.       $3,800,000 Capitalized Lease Obligation, covering the Toledo
                  Silo, with a final maturity of 12/06, issued to the
                  Toledo-Lucas County, port Authority, supported by a Letter of
                  Credit issued by PNC Bank, National Association.*

         3.       $57,500,000 Convertible Subordinated Notes.

         4.       $365,000 Mortgage Notes payable at 6.16%, maturing October 31,
                  2004, payable in 9 equal annual payments.*










----------------
  * Secured Debt








<PAGE>   48



                                    EXHIBIT A


                                 PROMISSORY NOTE



U.S. $                                                  Dated:             , 19
      --------------------                                   -----------



         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of (the
"BANK") for the account of its Applicable Lending Office (as defined in the
Credit Agreement referred to below) the principal sum of U.S.
___________________________ DOLLARS AND NO CENTS ($____________), on the
Termination Date (as defined in the Credit Agreement), or, if less, the
aggregate principal amount of the Advances (as defined below) made by the Bank
to the Borrower pursuant to the Credit Agreement outstanding on the Termination
Date.

         The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

         Both principal and interest are payable in lawful money of the United
States of America to Society National Bank, as Agent, for the benefit of the
Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds. Each
Advance made by the Bank to the Borrower pursuant to the Credit Agreement, and
all payments made on account of the principal amount thereof, shall be recorded
by the Bank and, prior to any transfer hereof, endorsed on the grid attached
hereto which is part of this Promissory Note.

         This Promissory Note is one of the Notes referred to in, and is
entitled to the benefits of, the Amended and Restated Revolving Credit Agreement
dated as of January 27, 1993 and amended and restated as of December 15, 1995
(as so amended and restated and as hereinafter amended or otherwise modified,
the "CREDIT AGREEMENT") among the Borrower, the Bank and certain other banks
parties thereto, and Society National Bank, as Agent for the Bank and such other
banks. The Credit Agreement, among other things, (i) provides for the making of
advances (the "ADVANCES") by the Bank to the Borrower from time to time in an
aggregate amount not to exceed at any time outstanding the U.S. dollar amount
first above mentioned, the indebtedness of the Borrower resulting from each such
Advance being evidenced by this Promissory Note, and (ii) contains provisions
for acceleration of the maturity hereof upon the happening of certain stated
events and also for prepayments on account of principal hereof prior to the
maturity hereof upon the terms and conditions therein specified.


                                            MEDUSA CORPORATION


                                            BY:
                                               ------------------------------
                                                TITLE: VICE PRESIDENT-FINANCE









<PAGE>   49




                       ADVANCES AND PAYMENTS OF PRINCIPAL




                              Amount of                           
                 Amount of    Principal Paid or   Unpaid Principal  Notation
NOTATION DATE    Advance      Prepaid             Balance           Made By
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<PAGE>   50



                                   EXHIBIT B

                              NOTICE OF BORROWING

                                     [Date]

Society National Bank,
         as Agent
127 Public Square
Cleveland, Ohio 44114-1306
         Attention:        Thomas J. Purcell
                           Assistant Vice President
                           Large Corporate Group
Gentlemen:

         The undersigned, Medusa Corporation, refers to the Amended and Restated
Revolving Credit Agreement, dated as of January 27, 1993 and amended and
restated as of December 15, 1995 (the "CREDIT AGREEMENT", the terms defined
therein being used herein as therein defined), among the undersigned, certain
Banks parties thereto and Society National Bank, as Agent for said Banks, and
hereby gives you notice, irrevocably, pursuant to section 2.02 of the Credit
Agreement that the undersigned hereby requests a Borrowing under the Credit
Agreement, and in that connection sets forth below the information relating to
such Borrowing (the "PROPOSED BORROWING") as required by section 2.02(a) of the
Credit Agreement:

               (i) The Business Day of the Proposed Borrowing is _______, 19__.
          

               (ii) The Type of Advances comprising the Proposed Borrowing is
          [Adjusted Base Rate Advances] [Eurodollar Rate Advances].

               (iii) The aggregate amount of the Proposed Borrowing is 
          $________________. 

               *[(iv) The initial Interest Period for each Advance made as part
          of the Proposed Borrowing is [ months]. --



*        To be included for a Proposed Borrowing comprised of
         Eurodollar Rate Advances.

         The undersigned hereby certifies that the following statements are true
on the date hereof, and will be true on the date of the Proposed Borrowing: (A)
the representations and warranties contained in section 4.01 of the Credit
Agreement are correct, before and after giving effect to the Proposed Borrowing
and to the application of the proceeds therefrom, as though made on and as of
such date; and (B) no event has occurred and is continuing, or would result from
such Proposed Borrowing or from the application of the proceeds therefrom, which
constitutes an Event of Default or would constitute an Event of Default but for
the requirement that notice be given or time elapse or both.

                                            Very truly yours,

                                            MEDUSA CORPORATION



                                            By:
                                               -------------------
                                               Title: 
                                                     ---------------



<PAGE>   51



                                    EXHIBIT C


                          [Restatement Effective Date]


To each of the Banks parties to the Amended and Restated Revolving Credit
  Agreement dated as of January 27, 1993 and amended and restated as of December
  15, 1995, among Medusa Corporation, said Banks and Society National Bank as
  Agent for said Banks, and to Society National Bank, as Agent

                           Re:  AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT
                              
Ladies and Gentlemen:

         This opinion is furnished to you pursuant to section 3.01(d) of the
Amended and Restated Revolving Credit Agreement, dated as of January 27, 1993
and amended and restated as of December 15, 1995 (the "CREDIT AGREEMENT"), among
Medusa Corporation (the "BORROWER"), the Banks parties thereto and Society
National Bank, as Agent for said Banks. Terms defined in the Credit Agreement
are used herein as therein defined.

         I am the General Counsel and Secretary of the Borrower and have acted
as counsel for the Borrower in connection with the preparation, execution and
delivery of the Credit Agreement.

         In that connection, I have examined:

                  (1)      The Credit Agreement.

                  (2) The Articles of Incorporation of the Borrower and all
         amendments thereto (the "CHARTER").

                  (3) The Code of Regulations of the Borrower and all amendments
         thereto (the "CODE OF REGULATIONS").

                  (4) A certificate of the Secretary of State of the State of
         Ohio, dated January 19 , 1993, attesting to the continued corporate
         existence and good standing of the Borrower in that State.

I have also examined the originals, or copies certified to my satisfaction, of
the documents referred to in the last sentence of section 4.01(g) of the Credit
Agreement (the "RESTRICTIVE AGREEMENTS"). In addition, I have examined the
originals, or copies certified to my satisfaction, of such other corporate
records of the Borrower, certificates of public officials and of officers of the
Borrower, and agreements, instruments and other documents, as I have deemed
necessary as a basis for the opinions expressed below. As to questions of fact
material to such opinions, I have, when relevant facts were not independently
established by me, relied upon certificates of the Borrower or its officers or
of public officials. I have assumed the due execution and delivery, pursuant to
due authorization, of the Credit Agreement by the Banks and the Agent.

         I am qualified to practice law in the State of Ohio and do not purport
to be an expert on any laws other than the laws of the State of Ohio and the
Federal laws of the United States.






<PAGE>   52



         Based upon the foregoing and upon such investigation as I have deemed
necessary, I am of the following opinion:

                  1. The Borrower is a corporation duly organized, validly
         existing and in good standing under the laws of the State of Ohio.

                  2. The execution, delivery and performance by the Borrower of
         the Credit Agreement and the Notes are within the Borrower's corporate
         powers, have been duly authorized by all necessary corporate action,
         and do not contravene (i) the Charter or the Code of Regulations, (ii)
         any law, rule or regulation applicable to the Borrower (including,
         without limitation, Regulation X of the Board of Governors of the
         Federal Reserve System), or (iii) any contractual or legal restriction
         contained in any Restrictive Agreement or, to the best of my knowledge,
         contained in any other similar document.

                  3. The Credit Agreement and the Notes have been duly executed
         and delivered on behalf of the Borrower. The Credit Agreement and the
         Notes each constitute a valid and binding agreement or obligation of
         the Borrower enforceable against the Borrower in accordance with their
         terms.

                  4. No consent, approval or authorization of, or registration,
         filing or declaration with, any Governmental Body is required on the
         part of the Borrower for the valid execution and delivery of the Credit
         Agreement or the consummation of the transactions contemplated thereby,
         including the issuance and delivery of the Notes, or for the
         fulfillment of, or compliance by the Borrower with, the terms and
         provisions of the Credit Agreement and the Notes.

                  5. There are no pending or overtly threatened actions or
         proceedings against the Borrower or any of its Subsidiaries before any
         court, governmental agency or arbitrator which purport to affect the
         legality, validity, binding effect or enforceability of the Credit
         Agreement or any of the Notes or which might result in a Material
         Adverse Change in the Business or Condition of the Borrower or of the
         Borrower and its Subsidiaries taken as a whole.

                  6. The transactions contemplated by the Credit Agreement will
         not result in a violation of Regulation U or Regulation X of the Board
         of Governors of the Federal Reserve System.

                  7. The Borrower is not an "investment company" or a Person
         directly or indirectly "controlled" by or "acting on behalf of" an
         "investment company" within the meaning of the Investment Company Act
         of 1940, as amended. The Borrower is not a "holding company", or a
         "subsidiary company" of a "holding company", or an "affiliate" of a
         "holding company" or of a "subsidiary company" of a "holding company",
         as such terms are defined in the Public Utility Holding Company Act of
         1935, as amended.

         The opinions set forth above are subject to the following
qualifications:

                  (a) My opinion in the last sentence of paragraph 3 above is
         subject to the effect of any applicable bankruptcy, insolvency,
         reorganization, moratorium or similar law affecting creditors' rights
         generally.

                  (b) My opinion in the last sentence of paragraph 3 above is
         subject to the effect of general principles of equity, including
         (without limitation) concepts of materiality, reasonableness, good
         faith and fair dealing (regardless of whether considered in a
         proceeding in equity or at law).

         The opinions expressed herein are expressed solely to you and may not
be relied upon by any other persons for any reason, without the express written
consent of the undersigned.

                                               Very truly yours,




                                        2

<PAGE>   53




                                   EXHIBIT D


                           ASSIGNMENT AND ACCEPTANCE


                              Dated________, 19__



         Reference is made to the Amended and Restated Revolving Credit
Agreement, dated as of January 27, 1993 as amended and restated as of December
15, 1995 (the "CREDIT AGREEMENT"), among Medusa Corporation, an Ohio corporation
(the "BORROWER"), the Banks (as defined in the Credit Agreement) and Society
National Bank, as Agent for the Banks (the "AGENT"). Terms defined in the Credit
Agreement are used herein with the same meaning.

         (the "ASSIGNOR") and _____________ (the "ASSIGNEE") agree as follows:

         1.________________ The Assignor hereby sells and assigns to the
Assignee, and the Assignee hereby purchases and assumes from the Assignor, that
interest in and to all of the Assignor's rights and obligations under the Credit
Agreement as of the date hereof which represents the percentage interest
specified on Schedule 1 of all outstanding rights and obligations under the
Credit Agreement which are specified on Schedule 1, including, without
limitation, such interest in the Assignor's Commitment, the Advances owing to
the Assignor, the Note held by the Assignor, as set forth in section 1 of
Schedule 1. After giving effect to such sale and assignment, the Assignee's
Commitment and the amount of the Advances owing to the Assignee will be as set
forth in section 2 of Schedule 1.

         2. The Assignor (i) represents and warrants that it is the legal and
beneficial owner of the interest being assigned by it hereunder and that such
interest is free and clear of any adverse claim; (ii) makes no representation or
warranty and assumes no responsibility with respect to any statements,
warranties or representations made in or in connection with the Credit Agreement
or the execution, legality, validity, enforceability, genuineness, sufficiency
or value of the Credit Agreement or any other instrument or document furnished
pursuant thereto; (iii) makes no representation or warranty and assumes no
responsibility with respect to the financial condition of the Borrower or the
performance or observance by the Borrower of any of its obligations under the
Credit Agreement or any other instrument or document furnished pursuant thereto;
and (iv) attaches the Note referred to in paragraph 1 above and requests that
the Agent exchange such Note for a new Note payable to the order of the Assignee
in an amount equal to the Commitment assumed by the Assignee pursuant hereto,
and a new Note payable to the order of the Assignor in an amount equal to the
Commitment retained by the Assignor under the Credit Agreement, respectively, as
specified on Schedule 1 hereto.

         3. The Assignee (i) confirms that it has received a copy of the Credit
Agreement, together with copies of the financial statements referred to in
section 4.01(d) thereof and such other documents and information as it has
deemed appropriate to make its own credit analysis and decision to enter into
this Assignment and Acceptance; (ii) agrees that it will, independently and
without reliance upon the Agent, the Assignor or any other Bank and based on
such documents and information as it shall deem appropriate at the time,
continue to make its own credit decisions in taking or not taking action under
the Credit Agreement; (iii) confirms that it is an Eligible Assignee; (iv)
appoints and authorizes the Agent to take such action as agent on its behalf and
to exercise such powers under the Credit Agreement as are delegated to the Agent
by the terms thereof, together with such powers as are reasonably incidental
thereto; (v) agrees that it will perform in accordance with their terms all of
the obligations which by the terms of the Credit Agreement are required to be
performed by it as a Bank; [and] (vi) specifies as its Domestic Lending Office
(and address for notices) and Eurodollar Lending Office the offices set forth
beneath its name on the signature pages hereof [and (vii) attaches the forms
prescribed by the Internal Revenue Service of the United States certifying as to
the Assignee's status for purposes of determining exemption from United States
withholding taxes with respect to all payments to be 

<PAGE>   54



made to the Assignee under the Credit Agreement and the Note or such other
documents as are necessary to indicate that all such payments are subject to
such rates at a rate reduced by an applicable tax treaty].1

         4. Following the execution of this Assignment and Acceptance by the
Assignor and the Assignee, it will be delivered to the Agent for acceptance and
recording by the Agent. The effective date of this Assignment and Acceptance
shall be the date of acceptance thereof by the Agent, unless otherwise specified
on Schedule 1 hereto (the "EFFECTIVE DATE").

         5. Upon such acceptance and recording by the Agent, as of the Effective
Date, (i) the Assignee shall be a party to the Credit Agreement and, to the
extent provided in this Assignment and Acceptance, have the rights and
obligations of a Bank thereunder and (ii) the Assignor shall, to the extent
provided in this Assignment and Acceptance, relinquish its rights and be
released from its obligations thereafter arising under the Credit Agreement.

         6. Upon such acceptance and recording by the Agent, from and after the
Effective Date, the Agent shall make all payments under the Credit Agreement and
the Notes in respect of the interest assigned hereby (including, without
limitation, all payments of principal, interest and commitment and facility fees
with respect thereto) to the Assignee. The Assignor and Assignee shall make all
appropriate adjustments in payments under the Credit Agreement and the Notes for
periods prior to the Effective Date directly between themselves.

         7. This Assignment and Acceptance shall be governed by, and construed
in accordance with, the laws of the State of Ohio.

         IN WITNESS WHEREOF, the parties hereto have caused this Assignment and
Acceptance to be executed by their respective officers thereunto duly
authorized, as of the date first above written, such execution being made on
Schedule 1 hereto.

--------
     1 If the Assignee is organized under the laws of the jurisdiction outside
the United States.





                                        2

<PAGE>   55



                                   SCHEDULE 1
                                       TO
                            ASSIGNMENT AND ACCEPTANCE

                                   Dated _____________, 19____

SECTION 1.

         Percentage Interest:      ______________%

SECTION 2.

         Assignee's Commitment:                      $________________
         Aggregate Outstanding Principal
           Amount of Advances owing to the Assignee:          $____________
         A Note payable to the Assignee
                                    Dated:__________________ , 19_______
                                    Principal amount:___________________

         A Note payable to the order of the Assignor
                                    Dated: __________________, 19_______ 
                                    Principal amount:___________________
SECTION 3.

         Effective Date(1):    ______________________, 19______

[NAME OF ASSIGNOR]

By:
   ----------------------------------
   Title:

[NAME OF ASSIGNEE]

By:
   -----------------------------------
   Title:

Domestic Lending Office (and address for notices):


Eurodollar Lending Office:
[Address]

--------
1 This date should be no earlier than the date of acceptance by the Agent.





<PAGE>   56




Accepted this ______day
of ___________, 19__

SOCIETY NATIONAL BANK, AS AGENT


By:
   --------------------------------------
   Title:





                                                         4

<PAGE>   57



                                    EXHIBIT E


                                    GUARANTY




         GUARANTY, dated ________, 19___, made by ___________, a [corporation]
organized and existing under the laws of (herein, together with its successors
and assigns, the "GUARANTOR"), in favor of the Banks (the "BANKS", such term to
include their respective successors and assigns) parties to the Credit Agreement
(as defined below) and SOCIETY NATIONAL BANK, a national banking association, as
agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

               (a) any lack of validity or enforceability of the Credit
          Agreement, the Notes or any other agreement or instrument relating
          thereto;
<PAGE>   58

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the Credit
         Agreement or the Notes, including, without limitation, any increase in
         the Obligations resulting from the extension of additional credit to
         the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e)  any change, restructuring or termination of the 
         corporate structure or existence of the Borrower or any of its 
         Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby 
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a [corporation] duly organized, validly existing and in good
         standing under the laws of the State of _____ and has all requisite
         power and authority to own or hold under lease, to carry on its
         business as now conducted and proposed to be conducted, to enter into
         this Guaranty and to perform its obligations hereunder. The Guarantor
         has, by all necessary [corporate] [partnership] [limited liability
         company] action (all action of [shareholders] [partners] [members], if
         any, required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2

<PAGE>   59

                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or
         violate any existing law, governmental rule or regulation or any Order
         of any court, arbitrator or Governmental Body applicable to the
         Guarantor which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at
______________, Attention: __________________, and if to the Agent or any Bank,
at its address specified in the Credit Agreement, or, as to any party, at such
other address as shall be designated by such party in a written notice to each
other party. All such notices and other communications shall, when mailed,
telecopied, telegraphed, telexed or cabled, be effective when deposited in the
mails, telecopied, delivered to the telegraph company, confirmed by telex
answerback or delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 


                                       3
<PAGE>   60

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

          SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                             [NAME OF GUARANTOR]




                                              By:
                                                 ----------------------------
                                                 Title:

                                       4
<PAGE>   61
                                 PROMISSORY NOTE



U.S. $17,500,000                                  Dated:  December 15, 1995



         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of SOCIETY
NATIONAL BANK (the "BANK") for the account of its Applicable Lending Office (as
defined in the Credit Agreement referred to below) the principal sum of U.S.
SEVENTEEN MILLION FIVE HUNDRED THOUSAND DOLLARS AND NO CENTS ($17,500,000.00),
on the Termination Date (as defined in the Credit Agreement), or, if less, the
aggregate principal amount of the Advances (as defined below) made by the Bank
to the Borrower pursuant to the Credit Agreement outstanding on the Termination
Date.

        The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

        Both principal and interest are payable in lawful money of the United
States of America to Society National Bank, as Agent, for the benefit of the
Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds. Each
Advance made by the Bank to the Borrower pursuant to the Credit Agreement, and
all payments made on account of the principal amount thereof, shall be recorded
by the Bank and, prior to any transfer hereof, endorsed on the grid attached
hereto which is part of this Promissory Note.

        This Promissory Note is one of the Notes referred to in, and is entitled
to the benefits of, the Amended and Restated Revolving Credit Agreement dated as
of January 27, 1993 and amended and restated as of December 15, 1995 (as so
amended and restated and as hereinafter amended or otherwise modified, the
"CREDIT AGREEMENT") among the Borrower, the Bank and certain other banks parties
thereto, and Society National Bank, as Agent for the Bank and such other banks.
The Credit Agreement, among other things, (i) provides for the making of
advances (the "ADVANCES") by the Bank to the Borrower from time to time in an
aggregate amount not to exceed at any time outstanding the U.S. dollar amount
first above mentioned, the indebtedness of the Borrower resulting from each such
Advance being evidenced by this Promissory Note, and (ii) contains provisions
for acceleration of the maturity hereof upon the happening of certain stated
events and also for prepayments on account of principal hereof prior to the
maturity hereof upon the terms and conditions therein specified.


                                      MEDUSA CORPORATION


                                      By: /s/ R. Breck Denny      
                                        ------------------------------------
                                        Title: Vice President-Finance




<PAGE>   62


                       ADVANCES AND PAYMENTS OF PRINCIPAL


                            Amount of
               Amount of    Principal Paid or  Unpaid Principal       Notation
Notation Date  Advance      Prepaid            Balance                Made By
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<PAGE>   63

                                 PROMISSORY NOTE



U.S. $10,000,000                                     Dated: December 15, 1995



         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of NBD BANK
(the "BANK") for the account of its Applicable Lending Office (as defined in the
Credit Agreement referred to below) the principal sum of U.S. TEN MILLION
DOLLARS AND NO CENTS DOLLARS AND NO CENTS ($10,000,000.00), on the Termination
Date (as defined in the Credit Agreement), or, if less, the aggregate principal
amount of the Advances (as defined below) made by the Bank to the Borrower
pursuant to the Credit Agreement outstanding on the Termination Date.

        The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

        Both principal and interest are payable in lawful money of the United
States of America to Society National Bank, as Agent, for the benefit of the
Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds. Each
Advance made by the Bank to the Borrower pursuant to the Credit Agreement, and
all payments made on account of the principal amount thereof, shall be recorded
by the Bank and, prior to any transfer hereof, endorsed on the grid attached
hereto which is part of this Promissory Note.

        This Promissory Note is one of the Notes referred to in, and is entitled
to the benefits of, the Amended and Restated Revolving Credit Agreement dated as
of January 27, 1993 and amended and restated as of December 15, 1995 (as so
amended and restated and as hereinafter amended or otherwise modified, the
"CREDIT AGREEMENT") among the Borrower, the Bank and certain other banks parties
thereto, and Society National Bank, as Agent for the Bank and such other banks.
The Credit Agreement, among other things, (i) provides for the making of
advances (the "ADVANCES") by the Bank to the Borrower from time to time in an
aggregate amount not to exceed at any time outstanding the U.S. dollar amount
first above mentioned, the indebtedness of the Borrower resulting from each such
Advance being evidenced by this Promissory Note, and (ii) contains provisions
for acceleration of the maturity hereof upon the happening of certain stated
events and also for prepayments on account of principal hereof prior to the
maturity hereof upon the terms and conditions therein specified.


                                      MEDUSA CORPORATION


                                      By: /s/ R. Breck Denny     
                                        ------------------------------------
                                        Title: Vice President-Finance




<PAGE>   64


                       ADVANCES AND PAYMENTS OF PRINCIPAL



                            Amount of
               Amount of    Principal Paid or  Unpaid Principal       Notation
Notation Date  Advance      Prepaid            Balance                Made By
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<PAGE>   65
                                 PROMISSORY NOTE



U.S. $10,000,000                                     Dated: December 15, 1995



        FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of NATIONAL
CITY BANK (the "BANK") for the account of its Applicable Lending Office (as
defined in the Credit Agreement referred to below) the principal sum of U.S. TEN
MILLION DOLLARS AND NO CENTS ($10,000,000.00), on the Termination Date (as
defined in the Credit Agreement), or, if less, the aggregate principal amount of
the Advances (as defined below) made by the Bank to the Borrower pursuant to the
Credit Agreement outstanding on the Termination Date.

        The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

        Both principal and interest are payable in lawful money of the United
States of America to Society National Bank, as Agent, for the benefit of the
Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds. Each
Advance made by the Bank to the Borrower pursuant to the Credit Agreement, and
all payments made on account of the principal amount thereof, shall be recorded
by the Bank and, prior to any transfer hereof, endorsed on the grid attached
hereto which is part of this Promissory Note.

        This Promissory Note is one of the Notes referred to in, and is entitled
to the benefits of, the Amended and Restated Revolving Credit Agreement dated as
of January 27, 1993 and amended and restated as of December 15, 1995 (as so
amended and restated and as hereinafter amended or otherwise modified, the
"CREDIT AGREEMENT") among the Borrower, the Bank and certain other banks parties
thereto, and Society National Bank, as Agent for the Bank and such other banks.
The Credit Agreement, among other things, (i) provides for the making of
advances (the "ADVANCES") by the Bank to the Borrower from time to time in an
aggregate amount not to exceed at any time outstanding the U.S. dollar amount
first above mentioned, the indebtedness of the Borrower resulting from each such
Advance being evidenced by this Promissory Note, and (ii) contains provisions
for acceleration of the maturity hereof upon the happening of certain stated
events and also for prepayments on account of principal hereof prior to the
maturity hereof upon the terms and conditions therein specified.


                                      MEDUSA CORPORATION


                                      By: /s/ R. Breck Denny      
                                        ------------------------------------
                                        Title: Vice President-Finance




<PAGE>   66


                       ADVANCES AND PAYMENTS OF PRINCIPAL



                                                                             
                            Amount of
               Amount of    Principal Paid or  Unpaid Principal       Notation
Notation Date  Advance      Prepaid            Balance                Made By
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<PAGE>   67
                                 PROMISSORY NOTE



U.S. $7,500,000                                      Dated: December 15, 1995



        FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of PNC BANK,
NATIONAL ASSOCIATION (the "BANK") for the account of its Applicable Lending
Office (as defined in the Credit Agreement referred to below) the principal sum
of U.S. SEVEN MILLION FIVE HUNDRED THOUSAND DOLLARS AND NO CENTS
($7,500,000.00), on the Termination Date (as defined in the Credit Agreement),
or, if less, the aggregate principal amount of the Advances (as defined below)
made by the Bank to the Borrower pursuant to the Credit Agreement outstanding on
the Termination Date.

        The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

        Both principal and interest are payable in lawful money of the United
States of America to Society National Bank, as Agent, for the benefit of the
Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds. Each
Advance made by the Bank to the Borrower pursuant to the Credit Agreement, and
all payments made on account of the principal amount thereof, shall be recorded
by the Bank and, prior to any transfer hereof, endorsed on the grid attached
hereto which is part of this Promissory Note.

        This Promissory Note is one of the Notes referred to in, and is entitled
to the benefits of, the Amended and Restated Revolving Credit Agreement dated as
of January 27, 1993 and amended and restated as of December 15, 1995 (as so
amended and restated and as hereinafter amended or otherwise modified, the
"CREDIT AGREEMENT") among the Borrower, the Bank and certain other banks parties
thereto, and Society National Bank, as Agent for the Bank and such other banks.
The Credit Agreement, among other things, (i) provides for the making of
advances (the "ADVANCES") by the Bank to the Borrower from time to time in an
aggregate amount not to exceed at any time outstanding the U.S. dollar amount
first above mentioned, the indebtedness of the Borrower resulting from each such
Advance being evidenced by this Promissory Note, and (ii) contains provisions
for acceleration of the maturity hereof upon the happening of certain stated
events and also for prepayments on account of principal hereof prior to the
maturity hereof upon the terms and conditions therein specified.


                                      MEDUSA CORPORATION


                                      By: /s/ R. Breck Denny      
                                        ------------------------------------
                                        Title: Vice President-Finance




                                                         1
<PAGE>   68


                       ADVANCES AND PAYMENTS OF PRINCIPAL




                                                                             
                            Amount of
               Amount of    Principal Paid or  Unpaid Principal       Notation
Notation Date  Advance      Prepaid            Balance                Made By
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<PAGE>   69
[LOGO]

                        M E D U S A C 0 R P 0 R A T I 0 N

LEE AND MONTICELLO       CLEVELAND HEIGHTS, OHIO 44118         216/371-4000
                                                           FAX 216/371-2912
JOHN P. SIEGFRIED                                    
VICE PRESIDENT, SECRETARY                                     MAIL ADDRESS
AND GENERAL COUNSEL                                          P.O. BOX 5668
                                                           CLEVELAND 44101
                                    EXHIBIT C


                                                            December 15, 1995


To each of the Banks parties to the 
  Amended and Restated Revolving Credit 
  Agreement dated as of January 27, 1993 
  and amended and restated as of 
  December 15, 1995, among 
  Medusa Corporation, said Banks 
  and Society National Bank as Agent
  for said Banks, and to Society National
  Bank, as Agent


               Re: AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

Ladies and Gentlemen:

          This opinion is furnished to you pursuant to section 3.01(d) of the
Amended and Restated Revolving Credit Agreement, dated as of January 27, 1993
and amended and restated as of December 15, 1995 (the "CREDIT AGREEMENT"), among
Medusa Corporation (the "BORROWER"), the Banks parties thereto and Society
National Bank, as Agent for said Banks. Terms defined in the Credit Agreement
are used herein as therein defined.

          I am the General Counsel and Secretary of the Borrower and have acted
as counsel for the Borrower in connection with the preparation, execution and
delivery of the Credit Agreement.

     In that connection, I have examined:

                    (1) The Credit Agreement.

                    (2) The Articles of Incorporation of the Borrower and all
          amendments thereto (the "CHARTER").

                    (3) The Code of Regulations of the Borrower and all
          amendments thereto (the "CODE OF REGULATIONS").


<PAGE>   70

                    (4) A certificate of the Secretary of State of the State of
          Ohio, dated January 19, 1993, attesting to the continued corporate
          existence and good standing of the Borrower in that State.

          I have also examined the originals, or copies certified to my
satisfaction, of the documents referred to in the last sentence of section
4.01(g) of the Credit Agreement (the "RESTRICTIVE AGREEMENTS"). In addition, I
have examined the originals, or copies certified to my satisfaction, of such
other corporate records of the Borrower, certificates of public officials and of
officers of the Borrower, and agreements, instruments and other documents, as I
have deemed necessary as a basis for the opinions expressed below. As to
questions of fact material to such opinions, I have, when relevant facts were
not independently established by me, relied upon certificates of the Borrower or
its officers or of public officials. I have assumed the due execution and
delivery, pursuant to due authorization, of the Credit Agreement by the Banks
and the Agent.

          I am qualified to practice law in the State of Ohio and do not purport
to be an expert on any laws other than the laws of the State of Ohio and the
Federal laws of the United States.

          Based upon the foregoing and upon such investigation as I have deemed
necessary, I am of the following opinion:

                    1. The Borrower is a corporation duly organized, validly
          existing and in good standing under the laws of the State of Ohio.

                    2. The execution, delivery and performance by the Borrower
          of the Credit Agreement and the Notes are within the Borrower's
          corporate powers, have been duly authorized by all necessary corporate
          action, and do not contravene (i) the Charter or the Code of
          Regulations, (ii) any law, rule or regulation applicable to the
          Borrower (including, without limitation, Regulation X of the Board of
          Governors of the Federal Reserve System), or (iii) any contractual or
          legal restriction contained in any Restrictive Agreement or, to the
          best of my knowledge, contained in any other similar document.

                    3. The Credit Agreement and the Notes have been duly
          executed and delivered on behalf of the Borrower. The Credit Agreement
          and the Notes each constitute a valid and binding agreement or
          obligation of the Borrower enforceable against the Borrower in
          accordance with their terms.

                    4. No consent, approval or authorization of, or
          registration, filing or declaration with, any Governmental Body is
          required on the part of the Borrower for the valid execution and
          delivery of the Credit Agreement or the consummation of the
          transactions contemplated thereby, including the issuance and delivery
          of the Notes, or for the fulfillment of, or compliance by the Borrower
          with, the terms and provisions of the Credit Agreement and the Notes.

                    5. There are no pending or overtly threatened actions or
          proceedings against the Borrower or any of its Subsidiaries before any
          court, governmental agency or arbitrator which purport to affect the
          legality, validity, binding effect or enforceability of

                                       2


<PAGE>   71

          the Credit Agreement or any of the Notes or which might result in a
          Material Adverse Change in the Business or Condition of the Borrower
          or of the Borrower and its Subsidiaries taken as a whole.

                    6. The transactions contemplated by the Credit Agreement
          will not result in a violation of Regulation U or Regulation X of the
          Board of Governors of the Federal Reserve System.

                    7. The Borrower is not an "investment company" or a Person
          directly or indirectly "controlled" by or "acting on behalf of' an
          "investment company" within the meaning of the Investment Company Act
          of 1940, as amended. The Borrower is not a "holding company", or a
          "subsidiary company" of a "holding company", or an "affiliate" of a
          "holding company" or of a "subsidiary company" of a "holding company",
          as such terms are defined in the Public Utility Holding Company Act of
          1935, as amended.

          The opinions set forth above are subject to the following
          qualifications:

                    (a) My opinion in the last sentence of paragraph 3 above is
          subject to the effect of any applicable bankruptcy, insolvency,
          reorganization, moratorium or similar law affecting creditors' rights
          generally.

                    (b) My opinion in the last sentence of paragraph 3 above is
          subject to the effect of general principles of equity, including
          (without limitation) concepts of materiality, reasonableness, good
          faith and fair dealing (regardless of whether considered in a
          proceeding in equity or at law).

          The opinions expressed herein are expressed solely to you and may not
be relied upon by any other persons for any reason, without the express written
consent of the undersigned.

                                                  Very truly yours,
                                                  /s/ John P. Siegfried
                                                  John P. Siegfried

JPS: jvc

                                       3











<PAGE>   72


                 CERTIFIED RESOLUTIONS OF THE BOARD OF DIRECTORS

          I DO HEREBY CERTIFY, That I am the duly elected and qualified
Secretary of Medusa Corporation, a corporation organized and existing under the
laws of the State of Ohio, and the keeper of the records and corporate seal of
such corporation; that the following is a true and correct copy of a certain
resolution duly adopted by the Board of Directors by unanimous vote at a
regularly scheduled meeting held on September 25, 1995, at which time a quorum
was always present, and that the resolution below has not been amended, revised,
modified or rescinded:

                    "RESOLVED, that the Board hereby approves the terms and
          conditions of the revised Revolving Credit Agreement negotiated by the
          Company with four financial institutions in the face amount of $45.0
          million, expiring December 21, 2000, with interest rates, commitment
          fees and financial covenants substantially similar to the current
          Revolving Credit Agreement, alone with a off, delegation of sufficient
          authority to the officers of the Company in order to GIVE effect to
          this resolution, to enter into such agreements, and make such
          representations and covenants as are required in order to implement
          this resolution."

          IN WITNESS WHEREOF, I have hereunto affixed my name as Secretary and
have caused the corporate seal of such corporation to be hereto affixed this
Fourteenth day of December, 1995. 


                                        Respectfully submitted, 

                                        MEDUSA CORPORATION
(CORPORATE SEAL)

                                        By /s/ John P. Siegfried
                                          -------------------------------------
                                          John P. Siegfried
                                          Secretary


<PAGE>   73
                               Medusa Corporation
                          U.S. $45,000,000 Amended and
                      Restated Revolving Credit Agreement


                             INCUMBENCY CERTIFICATE


          The undersigned, R. Breck Denny, of Medusa Corporation, an Ohio
corporation, hereby certifies that the following named persons, from January 1,
1995, to this day, have been and are the officers of the corporation holding the
offices set forth opposite their names, and that set opposite each name is the
true and genuine signature of that person.

   NAME               TITLE                                        SIGNATURE

 R. B. Denny        Vice President-Finance and Treasurer  /s/ R. Breck Denny
                                                          -------------------
 John P. Siegfried  Vice President, Secretary and General Counsel 
                                                        /s/ John P. Siegfried
                                                        ----------------------
                                                                           

                  IN WITNESS WHEREOF, I have hereunto set my hand this 14th day
of De er, 1995.

                                                  /s/ R. Breck Denny
                                                  ----------------------------


          The undersigned, John P. Siegfried, hereby certifies that R. Breck
Denny is, on the date set forth above, the Vice President-Finance and Treasurer
of Medusa Corporation and that the foregoing signature of his is true and
genuine.


                                                     /s/ John P. Siegfried
                                                     -------------------------




Dated: December 14, 1995
<PAGE>   74
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by CANADIAN MEDUSA CEMENT
LIMITED, a corporation organized and existing under the laws of the Province of
Ontario, Canada (herein, together with its successors and assigns, the
"GUARANTOR"), in favor of the Banks (the "BANKS", such term to include their
respective successors and assigns) parties to the Credit Agreement (as defined
below) and SOCIETY NATIONAL BANK, a national banking association, as agent (the
"AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   75

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a corporation duly organized, validly existing and in good standing
         under the laws of the Province of Ontario, Canada, and has all
         requisite power and authority to own or hold under lease, to carry on
         its business as now conducted and proposed to be conducted, to enter
         into this Guaranty and to perform its obligations hereunder. The
         Guarantor has, by all necessary corporate action (all action of
         shareholders, if any, required therefor having been duly taken), duly
         authorized the execution and delivery of this Guaranty and the
         performance of its obligations under this Guaranty.

                                       2
<PAGE>   76

                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding 
         document) or by-law to which the Guarantor is a party or by which the 
         Guarantor or any of its properties may be bound or affected, or 
         violate any existing law, governmental rule or regulation or any
         Order of any court, arbitrator or Governmental Body applicable to the
         Guarantor which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119, 
attention: Chief Financial Officer, and if to the Agent or any Bank, at its 
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed,
telecopied, telegraphed, telexed or cabled, be effective when deposited in the
mails, telecopied, delivered to the telegraph company, confirmed by telex
answerback or delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   77

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       CANADIAN MEDUSA CEMENT LIMITED



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   78
                                    GUARANTY




         GUARANTY, dated December 16, 1995, made by MEDUSA PORTLAND CEMENT
COMPANY, a corporation organized and existing under the laws of the State of
Michigan (herein, together with its successors and assigns, the GUARANTOR), in
favor of the Banks (the "BANKS", such term to include their respective
successors and assigns) parties to the Credit Agreement (as defined below) and  
KEYBANK NATIONAL ASSOCIATION, a national banking association (successor by
merger to Society National Bank), as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and
amended and restated as of December 15, 1995, and as further amended by
Amendment No. 1, dated as of December 16, 1996, to Amended and Restated
Revolving Credit Agreement (said Agreement, as so amended, restated and amended
and as it may hereafter be amended or otherwise modified from time to time,
being the "CREDIT AGREEMENT," the terms defined therein and not otherwise
defined herein being used herein as therein defined) with Medusa Corporation, a
corporation organized and existing under the laws of Ohio (herein,
together with its successors and assigns, the "BORROWER"). The Guarantor may
receive a portion of the proceeds of the Advances under the Credit Agreement
and will derive substantial direct and indirect benefit from the transactions
contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without 
limiting the generality of the foregoing, the Guarantor's liability shall
extend to all amounts which constitute part of the Obligations and would be
owed by the Borrower to the Agent or the Banks under the Credit Agreement and
the Notes but for the fact that they are unenforceable or not allowable due to
the existence of a bankruptcy, reorganization or similar proceeding involving
the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

<PAGE>   79

                                    GUARANTY




         GUARANTY, dated December 16, 1995, made by MEDUSA AGGREGATES LLC, a
limited liability company organized and existing under the laws of the
Commonwealth of Pennsylvania (herein, together with its successors and assigns,
the "GUARANTOR"), in favor of the Banks (the "BANKS", such term to include their
respective successors and assigns) parties to the Credit Agreement (as defined
below) and KEYBANK NATIONAL ASSOCIATION, a national banking association 
(successor by merger to Society National Bank), as agent (the "AGENT") for the
Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995, and as further amended by Amendment No. 1,
dated as of December 16, 1996, to Amended and Restated Revolving Credit
Agreement (said Agreement, as so amended, restated and amended and as it may
hereafter be amended or otherwise modified from time to time, being the "CREDIT
AGREEMENT", the terms defined therein and not otherwise defined herein being 
used herein as therein defined) with Medusa Corporation, a corporation
organized and existing under the laws of Ohio (herein, together with its
successors and assigns, the "BORROWER"). The Guarantor may receive a portion of
the proceeds of the Advances under the Credit Agreement and will derive
substantial direct and indirect benefit from the transactions contemplated by
the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;


<PAGE>   80
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by CEMENT TRANSIT COMPANY, a
corporation organized and existing under the laws of the State of Delaware
(herein, together with its successors and assigns, the "GUARANTOR"), in favor of
the Banks (the "BANKS", such term to include their respective successors and
assigns) parties to the Credit Agreement (as defined below) and SOCIETY NATIONAL
BANK, a national banking association, as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   81

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a corporation duly organized, validly existing and in good standing
         under the laws of the State of Delaware and has all requisite power and
         authority to own or hold under lease, to carry on its business as now
         conducted and proposed to be conducted, to enter into this Guaranty and
         to perform its obligations hereunder. The Guarantor has, by all
         necessary corporate action (all action of shareholders, if any,
         required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   82
                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   83
section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       CEMENT TRANSIT COMPANY



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   84
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by MEDUSA AGGREGATES COMPANY, a
corporation organized and existing under the laws of the State of Iowa (herein,
together with its successors and assigns, the "GUARANTOR"), in favor of the
Banks (the "BANKS", such term to include their respective successors and
assigns) parties to the Credit Agreement (as defined below) and SOCIETY NATIONAL
BANK, a national banking association, as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   85

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a corporation duly organized, validly existing and in good standing
         under the laws of the State of Iowa and has all requisite power and
         authority to own or hold under lease, to carry on its business as now
         conducted and proposed to be conducted, to enter into this Guaranty and
         to perform its obligations hereunder. The Guarantor has, by all
         necessary corporate action (all action of shareholders, if any,
         required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   86
                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   87

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       MEDUSA AGGREGATES COMPANY



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   88
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by JAMES H. DREW CORPORATION, a
corporation organized and existing under the laws of the State of Indiana
(herein, together with its successors and assigns, the "GUARANTOR"), in favor of
the Banks (the "BANKS", such term to include their respective successors and
assigns) parties to the Credit Agreement (as defined below) and SOCIETY NATIONAL
BANK, a national banking association, as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   89

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a  corporation duly organized, validly existing and in good standing
         under the laws of the State of Indiana and has all requisite power and
         authority to own or hold under lease, to carry on its business as now
         conducted and proposed to be conducted, to enter into this Guaranty and
         to perform its obligations hereunder. The Guarantor has, by all
         necessary corporate action (all action of shareholders, if any,
         required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   90
                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   91

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       JAMES H. DREW CORPORATION



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   92
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by MEDUSA-CITADEL, INC., a
corporation organized and existing under the laws of the State of Alabama
(herein, together with its successors and assigns, the "GUARANTOR"), in favor of
the Banks (the "BANKS", such term to include their respective successors and
assigns) parties to the Credit Agreement (as defined below) and SOCIETY NATIONAL
BANK, a national banking association, as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   93

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a corporation duly organized, validly existing and in good standing
         under the laws of the State of Alabama and has all requisite power and
         authority to own or hold under lease, to carry on its business as now
         conducted and proposed to be conducted, to enter into this Guaranty and
         to perform its obligations hereunder. The Guarantor has, by all
         necessary corporate action (all action of shareholders, if any,
         required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   94
                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   95

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       JAMES H. DREW CORPORATION



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   96
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by MEDUSA-CRESCENT, INC., a
corporation organized and existing under the laws of State of Ohio (herein,
together with its successors and assigns, the "GUARANTOR"), in favor of the
Banks (the "BANKS", such term to include their respective successors and
assigns) parties to the Credit Agreement (as defined below) and SOCIETY NATIONAL
BANK, a national banking association, as agent (the "AGENT") for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   97

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a  corporation duly organized, validly existing and in good
         standing under the laws of the State of Ohio and has all requisite
         power and authority to own or hold under lease, to carry on its
         business as now conducted and proposed to be conducted, to enter into
         this Guaranty and to perform its obligations hereunder. The Guarantor
         has, by all necessary corporate action (all action of shareholders, if
         any, required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   98

                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage,

         instrument, corporate charter (or corresponding document) or by-law to
         which the Guarantor is a party or by which the Guarantor or any of its
         properties may be bound or affected, or violate any existing law,
         governmental rule or regulation or any Order of any court, arbitrator
         or Governmental Body applicable to the Guarantor which could have a
         Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   99

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       MEDUSA-CITADEL, INC.



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   100
                                    GUARANTY


         GUARANTY, dated December 15, 1995 made by THE THOMASVILLE STONE AND
LIME COMPANY, a corporation organized and existing under the laws of State of
Maryland (herein, together with its successors and assigns, the "GUARANTOR"), in
favor of the Banks (the "BANKS", such term to include their respective
successors and assigns) parties to the Credit Agreement (as defined below) and
SOCIETY NATIONAL BANK, a national banking association, as agent (the "AGENT")
for the Banks:

         PRELIMINARY STATEMENTS:

         (1) The Banks and the Agent have entered into an Amended and Restated
Revolving Credit Agreement, originally dated as of January 27, 1993, and amended
and restated as of December 15, 1995 (said Agreement, as it may hereafter be
amended or otherwise modified from time to time, being the "CREDIT AGREEMENT",
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with Medusa Corporation, a corporation organized and existing
under the laws of Ohio (herein, together with its successors and assigns, the
"BORROWER"). The Guarantor may receive a portion of the proceeds of the Advances
under the Credit Agreement and will derive substantial direct and indirect
benefit from the transactions contemplated by the Credit Agreement.

         (2) It is a condition precedent to the making of Advances by the Banks
under the Credit Agreement that the Guarantor shall have executed and delivered
this Guaranty.

         NOW, THEREFORE, in consideration of the premises and in order to induce
the Banks to make Advances under the Credit Agreement, the Guarantor hereby
agrees as follows:

         SECTION 1. GUARANTY. The Guarantor hereby unconditionally guarantees
the punctual payment when due, whether at stated maturity, by acceleration or
otherwise, of all obligations of the Borrower now or hereafter existing under
the Credit Agreement and the Notes, whether for principal, interest, fees,
expenses or otherwise (such obligations being the "OBLIGATIONS"), and agrees to
pay any and all expenses (including counsel fees and expenses) incurred by the
Agent or the Banks in enforcing any rights under this Guaranty. Without limiting
the generality of the foregoing, the Guarantor's liability shall extend to all
amounts which constitute part of the Obligations and would be owed by the
Borrower to the Agent or the Banks under the Credit Agreement and the Notes but
for the fact that they are unenforceable or not allowable due to the existence
of a bankruptcy, reorganization or similar proceeding involving the Borrower.

         SECTION 2. GUARANTY ABSOLUTE. The Guarantor guarantees that the
Obligations will be paid strictly in accordance with the terms of the Credit
Agreement and the Notes, regardless of any law, regulation or order now or
hereafter in effect in any jurisdiction affecting any of such terms or the
rights of the Agent or the Banks with respect thereto. The obligations of the
Guarantor under this Guaranty are independent of the Obligations, and a separate
action or actions may be brought and prosecuted against the Guarantor to enforce
this Guaranty, irrespective of whether any action is brought against the
Borrower or whether the Borrower is joined in any such action or actions. The
liability of the Guarantor under this Guaranty shall be absolute and
unconditional irrespective of:

                  (a) any lack of validity or enforceability of the Credit
         Agreement, the Notes or any other agreement or instrument relating
         thereto;

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the 


<PAGE>   101

         Credit Agreement or the Notes, including, without limitation, any
         increase in the Obligations resulting from the extension of additional
         credit to the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral, or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter existing. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a  corporation duly organized, validly existing and in good
         standing under the laws of the State of Maryland and has all requisite
         power and authority to own or hold under lease, to carry on its
         business as now conducted and proposed to be conducted, to enter into
         this Guaranty and to perform its obligations hereunder. The Guarantor
         has, by all necessary corporate action (all action of shareholders, if
         any, required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.

                                       2
<PAGE>   102
                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transactions contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION. There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal,
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                  (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and without
         reliance upon the Agent or any Bank and based on such documents and
         information as it has deemed appropriate, made its own credit analysis
         and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address at c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit Agreement to
authorize the Agent to declare the Notes due and payable pursuant to the
provisions of said 

                                       3
<PAGE>   103

section 6.01, each Bank is hereby authorized at any time and from time to time,
to the fullest extent permitted by law, to set off and apply any and all
deposits (general or special, time or demand, provisional or final) at any time
held and other indebtedness at any time owing by such Bank to or for the credit
or the account of the Guarantor against any and all of the obligations of the
Guarantor now or hereafter existing under this Guaranty, whether or not such
Bank shall have made any demand under this Guaranty and although such
obligations may be contingent and unmatured. Each Bank agrees promptly to notify
the Guarantor after any such set-off and application made by such Bank,
PROVIDED that the failure to give such notice shall not affect the validity of
such set-off and application. The rights of each Bank under this section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11. GOVERNING LAW. This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                       THE THOMASVILLE STONE AND LIME COMPANY



                                       By: /s/ R. Breck Denny
                                          ---------------------------
                                            Title: Vice President and
                                                   Treasurer

                                       4
<PAGE>   104
===============================================================================


                               MEDUSA CORPORATION
                                 as the Borrower

                                       And

                             THE BANKS NAMED HEREIN
                                    as Banks

                                       And

                          KEYBANK NATIONAL ASSOCIATION
                                    as Agent











                              ---------------------

                                 AMENDMENT NO. 1
                                   dated as of
                                December 16, 1996

                                       to

                 AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT
                                   dated as of
                                January 27, 1993
                         and amended and restated as of
                                December 15, 1995
                              ---------------------








==============================================================================
<PAGE>   105




                                 AMENDMENT NO. 1
                                       TO
                 AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

         THIS AMENDMENT NO. 1 TO AMENDED AND RESTATED REVOLVING CREDIT
AGREEMENT, dated as of December 16, 1996, among MEDUSA CORPORATION, an Ohio
corporation (herein, together with its successors and assigns, the "BORROWER");
the Banks party to the Credit Agreement referred to below (the "BANKS"); and
KEYBANK NATIONAL ASSOCIATION, a national banking association which is successor
by merger to Society National Bank, as Agent for the Banks under such Credit
Agreement:


PRELIMINARY STATEMENTS:

         (1) The Borrower, the Banks named therein, and the the Agent entered
into the Amended and Restated Revolving Credit Agreement, dated as of January
27, 1993 and amended and restated as of December 15, 1995 (the "CREDIT
AGREEMENT"; with the terms defined therein, or the definitions of which are
incorporated therein, being used herein as so defined).

         (2) The Borrower, the Banks, and the Agent desire to amend certain of
the terms and provisions of the Credit Agreement in order, among other things,
to increase the aggregate amount of the Commitments of the Banks from
$45,000,000 to $65,000,000, to extend the existing Termination Date from
December 31, 2000 to December 31, 2001, and to delete the covenant restricting
the incurrance of Current Debt, and to make certain other modifications to the
terms and provisions thereof, all as more fully set forth below.

         NOW, THEREFORE, the parties hereby agree as follows:

         SECTION 1.        AMENDMENTS.

         1.1. REVISED COMMITMENT AMOUNTS. Effective on the Effective Date (as
hereinafter defined), (i) the respective Commitments of the Banks appearing
opposite their signatures to the Credit Agreement are changed to the amounts and
percentages indicated below:

<TABLE>
<CAPTION>
         Name of Bank                        Commitment Amount     Percentage
         ------------                        ----------------      -----------
<S>                                              <C>                <C>     
         KeyBank National Association            $25,000,000        38.4615%
         National City Bank                      $14,000,000        21.5385%
         NBD Bank                                $14,000,000        21.5385%
         PNC Bank, National Association          $12,000,000        18.4615%
</TABLE>

; and (ii) the amount "$45,000,000" which appears on the cover page of the
Credit Agreement and as the Total of the Commitments on the page of the Credit
Agreement containing the signatures of the Banks is changed in each such
instance to "$65,000,000".

         1.2. EXTENSION OF MATURITY. Effective on the Effective Date, the date
"December 31, 2000" which appears in the definition of the term "TERMINATION
DATE" in section 1.01 of the Credit Agreement is changed to "December 31, 2001".

          1.3. CURRENT DEBT COVENANT. Effective on the Effective Date, the
covenant contained in section 5.11 of the Credit Agreement shall be of no
further force or effect.

         1.4. REPRESENTATIONS AS TO CHANGES, ETC. Effective on the Effective
Date, the phrase "Since the date of the most recent audited balance sheet
referred to in section 4.01(d)" which appears at the beginning of section
4.01(e) of the Credit Agreement, is changed to "Since December 31, 1995".


<PAGE>   106




         SECTION 2.        REPRESENTATIONS AND WARRANTIES.

         The Borrower represents and warrants that: (a) the Borrower has
delivered to the Agent and each Bank prior to the execution of this Amendment
true, correct and complete copies of the consolidated financial statements of
the Borrower and its consolidated subsidiaries for the fiscal year ended
December 31, 1995 and for the nine months ended September 30, 1996, such
consolidated financial statements have been prepared in accordance with
generally accepted accounting principles, consistently applied (except as noted
therein), and fairly present the consolidated financial condition of the
Borrower and its consolidated subsidiaries at such dates and the consolidated
results of their operations and cash flows for the periods then ended; (b) this
Amendment has been duly authorized by all necessary corporate action on the part
of the Borrower, has been duly executed and delivered by a duly authorized
officer or officers of the Borrower, and constitutes the valid and binding
agreement of the Borrower, enforceable against the Borrower in accordance with
its terms; (c) the representations and warranties of the Borrower contained in
the Credit Agreement, as amended hereby, are true and correct on and as of the
date hereof as though made on and as of the date hereof; (d) no condition or
event has occurred or exists which constitutes or which, after notice or lapse
of time or both, would constitute an Event of Default; and (e) the Borrower is
in full compliance with all covenants and agreements contained in the Credit
Agreement, as amended hereby.


         SECTION 3.        RATIFICATIONS.

         The terms and provisions set forth in this Amendment shall modify and
supersede all inconsistent terms and provisions set forth in the Credit
Agreement, and except as expressly modified and superseded by this Amendment,
the terms and provisions of the Credit Agreement are ratified and confirmed and
shall continue in full force and effect.


         SECTION 4.        BINDING EFFECT.

         This Amendment shall become effective on December 16, 1996 (the
"EFFECTIVE DATE") if and when, on or prior to such date,

                  (i) this Amendment shall have been executed by the Borrower
         and the Agent, and counterparts hereof as so executed shall have been
         delivered to the Agent,

                  (ii) the Acknowledgment and Consent appended hereto shall have
         been executed by the Subsidiaries of the Borrower named therein, and
         counterparts thereof as so executed shall have been delivered to the
         Agent,

                  (iii) the Agent shall have been notified by all of the Banks
         that such Banks have executed this Amendment (which notification may be
         by facsimile or other written confirmation of such execution),

                  (iv) certified copies of the resolutions of the Board of
         Directors of the Borrower approving this Amendment, and of all
         documents evidencing other necessary corporate action and governmental
         approvals, if any, with respect to the execution, delivery and
         performance by the Borrower of this Amendment, shall have been
         delivered to the Agent on or within five days prior to the Effective
         Date, in sufficient original copies for the Agent and the Banks,

                  (v) a certificate of the Secretary or an Assistant Secretary
         of the Borrower, certifying the names and true signatures of the
         officers of the Borrower authorized to sign this Amendment and the
         other documents to which the Borrower is to be a party which are
         referred to herein, shall have been delivered to the Agent on or within
         five days prior to the Effective Date, in sufficient original copies
         for the Agent and the Banks,

                                        2

<PAGE>   107




                  (vi) a favorable opinion of John P. Siegfried, General Counsel
         and Secretary of the Borrower, satisfactory in form and substance to
         the Agent and the Banks and substantially in the form of Exhibit A
         hereto and as to such other matters as any Bank through the Agent may
         reasonably request, shall have been delivered to the Agent on or within
         five days prior to the Effective Date, in sufficient original copies
         for the Agent and the Banks,

                  (vii) Notes of the Borrower to the order of the Banks shall
         have been duly executed and delivered to the Agent for delivery to the
         Banks in replacement of Notes previously issued to the Banks, and

                  (viii) the Agent shall have notified the Borrower and each
         Bank in writing that the conditions specified in the foregoing clauses
         have been satisfied;

and thereafter this Amendment shall be binding upon and inure to the benefit of
the Borrower, the Agent and each Bank and their respective permitted successors
and assigns, except that the Borrower shall not have the right to assign its
rights hereunder or any interest herein without the prior written consent of the
Majority Banks.


         SECTION 5.        MISCELLANEOUS.

         5.1. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations
and warranties made in this Amendment shall survive the execution and delivery
of this Amendment, and no investigation by any Agent or any Bank or any
subsequent Advance shall affect the representations and warranties or the right
of the Agent or any Bank to rely upon them.

         5.2. REFERENCE TO CREDIT AGREEMENT. The Credit Agreement and any and
all other agreements, instruments or documentation now or hereafter executed and
delivered pursuant to the terms of the Credit Agreement as amended hereby, are
hereby amended so that any reference therein to the Credit Agreement shall mean
a reference to the Credit Agreement as amended hereby.

         5.3. EXPENSES. As provided in the Credit Agreement, but without
limiting any terms or provisions thereof, the Borrower agrees to pay on demand
all costs and expenses incurred by the Agent in connection with the preparation,
negotiation, and execution of this Amendment, including without limitation the
costs and fees of the Agent's special legal counsel, regardless of whether this
Amendment becomes effective in accordance with the terms hereof, and all costs
and expenses incurred by the Agent or any Bank in connection with the
enforcement or preservation of any rights under the Credit Agreement, as amended
hereby.

         5.4. SEVERABILITY. Any term or provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the term or provision so held to be invalid or unenforceable.

          5.5. APPLICABLE LAW. This Amendment shall be governed by and construed
in accordance with the laws of the State of Ohio.

          5.6. HEADINGS. The headings, captions and arrangements used in this
Amendment are for convenience only and shall not affect the interpretation of
this Amendment.

         5.7. ENTIRE AGREEMENT. This Amendment is specifically limited to the
matters expressly set forth herein. This Amendment and all other instruments,
agreements and documentation executed and delivered in connection with this
Amendment embody the final, entire agreement among the parties hereto with
respect to the subject matter hereof and supersede any and all prior
commitments, agreements, representations and understandings, whether written or
oral, relating to the matters covered by this Amendment, and may not be
contradicted or varied by evidence of prior, contemporaneous or subsequent oral
agreements or discussions of

                                        3

<PAGE>   108



the parties hereto. There are no oral agreements among the parties hereto
relating to the subject matter hereof or any other subject matter relating to
the Credit Agreement.

         5.8. COUNTERPARTS. This Amendment may be executed by the parties hereto
separately in one or more counterparts, each of which when so executed shall be
deemed to be an original, but all of which when taken together shall constitute
one and the same agreement.

         IN WITNESS WHEREOF, this Amendment has been duly executed and delivered
as of the date first above written.


                                      MEDUSA CORPORATION


                                      BY:/s/ R. Breck Denny
                                         --------------------------------------
                                               VICE PRESIDENT-FINANCE



                                      KEYBANK NATIONAL ASSOCIATION,
                                               AS A BANK AND AS AGENT


                                      BY:/s/ Thomas J. Purcell
                                         --------------------------------------
                                               VICE PRESIDENT


                                      NATIONAL CITY BANK



                                      BY: /s/illegible
                                         --------------------------------------
                                               VICE PRESIDENT


                                      NBD BANK


                                      BY: /s/ illegible
                                         --------------------------------------
                                               VICE PRESIDENT


                                      PNC BANK, NATIONAL ASSOCIATION


                                      BY: /s/ illegible
                                         --------------------------------------
                                               VICE PRESIDENT



                                        4

<PAGE>   109



                                    EXHIBIT A

                                [Effective Date]

To each of the Banks and the Agent
         party to the Credit Agreement
         referred to below
c/o KeyBank National Association
Key Center
127 Public Square
Cleveland, Ohio 44114

                  Re:      U.S.$65,000,000 Credit Agreement
                           with Medusa Corporation
                           ---------------------------------
Ladies and Gentlemen:

         This opinion is furnished to you pursuant to section 4(vi) of Amendment
No. 1 to Amended and Restated Revolving Credit Agreement, dated as of December
16, 1996 (the "AMENDMENT"), among Medusa Corporation (the "BORROWER"), the Banks
parties thereto and KeyBank National Association (as successor to Society
National Bank), as Agent for said Banks. Terms defined in the Amendment or in
the Credit Agreement referred to in the Amendment are, unless otherwise defined
herein, used herein as therein defined.

         I am a Vice President and the General Counsel and Secretary of the
Borrower and have acted as counsel for the Borrower in connection with the
preparation, execution and delivery of the Credit Agreement and the Amendment.

         In that connection, I have examined:

                  (1)      The Credit Agreement and the Amendment.

                  (2) The Promissory Notes (the "NOTES") delivered by the
         Borrower to the Banks pursuant to the Amendment.

                  (3) The Articles of Incorporation of the Borrower and all
         amendments thereto (the "CHARTER").

                  (4) The Code of Regulations of the Borrower and all amendments
         thereto (the "CODE OF REGULATIONS").

                  (5) A certificate of the Secretary of State of the State of
         Ohio, dated January 19 , 1993, attesting to the continued corporate
         existence and good standing of the Borrower in that State.

I have also examined the originals, or copies certified to my satisfaction, of
the documents referred to in the last sentence of section 4.01(g) of the Credit
Agreement (the "RESTRICTIVE AGREEMENTS"). In addition, I have examined the
originals, or copies certified to my satisfaction, of such other corporate
records of the Borrower, certificates of public officials and of officers of the
Borrower, and agreements, instruments and other documents, as I have deemed
necessary as a basis for the opinions expressed below. As to questions of fact
material to such opinions, I have, when relevant facts were not independently
established by me, relied upon certificates of the Borrower or its officers or
of public officials. I have assumed the due execution and delivery, pursuant to
due authorization, of the Credit Agreement and the Amendment by the Banks and
the Agent.

         I am qualified to practice law in the State of Ohio and do not purport
to be an expert on any laws other than the laws of the State of Ohio and the
Federal laws of the United States.


<PAGE>   110




         Based upon the foregoing and upon such investigation as I have deemed
necessary, I am of the following opinion:

         1. The Borrower is a corporation duly organized, validly existing and
in good standing under the laws of the State of Ohio.

         2. The execution, delivery and performance by the Borrower of the
Credit Agreement, the Amendment and the Notes are within the Borrower's
corporate powers, have been duly authorized by all necessary corporate action,
and do not contravene (i) the Charter or the Code of Regulations, (ii) any law,
rule or regulation applicable to the Borrower (including, without limitation,
Regulation X of the Board of Governors of the Federal Reserve System), or (iii)
any contractual or legal restriction contained in any Restrictive Agreement or,
to the best of my knowledge, contained in any other similar document.

         3. The Credit Agreement, the Amendment and the Notes have been duly
executed and delivered on behalf of the Borrower. The Credit Agreement (as
amended by the Amendment) and the Notes each constitute a valid and binding
agreement or obligation of the Borrower enforceable against the Borrower in
accordance with their terms.

         4. No consent, approval or authorization of, or registration, filing or
declaration with, any Governmental Body is required on the part of the Borrower
for the valid execution and delivery of the Credit Agreement or the Amendment or
the consummation of the transactions contemplated thereby, including the
issuance and delivery of the Notes, or for the fulfillment of, or compliance by
the Borrower with, the terms and provisions of the Credit Agreement (as amended
by the Amendment) and the Notes.

         5. There are no pending or overtly threatened actions or proceedings
against the Borrower or any of its Subsidiaries before any court, governmental
agency or arbitrator which purport to affect the legality, validity, binding
effect or enforceability of the Credit Agreement or the Amendment or any of the
Notes or which might result in a Material Adverse Change in the Business or
Condition of the Borrower or of the Borrower and its Subsidiaries taken as a
whole.

         6. The transactions contemplated by the Credit Agreement (as amended by
the Amendment) will not result in a violation of Regulation U or Regulation X of
the Board of Governors of the Federal Reserve System.

         7. The Borrower is not an "investment company" or a Person directly or
indirectly "controlled" by or "acting on behalf of" an "investment company"
within the meaning of the Investment Company Act of 1940, as amended. The
Borrower is not a "holding company", or a "subsidiary company" of a "holding
company", or an "affiliate" of a "holding company" or of a "subsidiary company"
of a "holding company", as such terms are defined in the Public Utility Holding
Company Act of 1935, as amended.

         The opinions set forth above are subject to the following
qualifications:

         (a) My opinion in the last sentence of paragraph 3 above is subject to
the effect of any applicable bankruptcy, insolvency, reorganization, moratorium
or similar law affecting creditors' rights generally.

         (b) My opinion in the last sentence of paragraph 3 above is subject to
the effect of general principles of equity, including (without limitation)
concepts of materiality, reasonableness, good faith and fair dealing (regardless
of whether considered in a proceeding in equity or at law).

         The opinions expressed herein are expressed solely to you and may not
be relied upon by any other persons for any reason, without the express written
consent of the undersigned.

                                              Very truly yours,


                                        2

<PAGE>   111



                           ACKNOWLEDGMENT AND CONSENT

         Each of the undersigned is a party to a Guaranty (as such term is
defined in the Credit Agreement referred to in the Amendment No. 1 to Amended
and Restated Revolving Credit Agreement (the "AMENDMENT"), to which this
Acknowledgment and Consent is appended).

         For the avoidance of doubt, and without limitation of the intent and
effect of sections 2 and 3 of any Guaranty to which any of the undersigned is a
party, each of the undersigned hereby unconditionally and irrevocably (i)
acknowledges receipt of a copy of the Credit Agreement and the Amendment, and
(ii) consents to all of the terms and provisions of the Credit Agreement as
amended by the Amendment.

         Capitalized terms which are used herein without definition shall have
the respective meanings ascribed thereto in the Credit Agreement referred to
herein. This Acknowledgment and Consent is for the benefit of the Banks and the
Agent, any other person who is a third party beneficiary of a Guaranty, and
their respective successors and assigns. No term or provision of this
Acknowledgment and Consent may be modified or otherwise changed without the
prior written consent of the Agent, given as provided in the Credit Agreement.
This Acknowledgment and Consent shall be binding upon the successors and assigns
of each of the undersigned. This Acknowledgment and Consent may be executed by
any of the undersigned in separate counterparts, each of which shall be an
original and all of which together shall constitute one and the same instrument.

         IN WITNESS WHEREOF, each of the undersigned has duly executed and
delivered this Acknowledgment and Consent as of the date of the Amendment
referred to herein.

CANADIAN MEDUSA CEMENT LIMITED              MEDUSA-CITADEL, INC.


BY: /s/ R. Breck Denny                      BY:   /s/ R. Breck Denny
   -----------------------------               --------------------------------
         VICE PRESIDENT                         VICE PRESIDENT

CEMENT TRANSIT COMPANY                      MEDUSA-CRESCENT, INC.


BY: /s/ R. Breck Denny                      BY:  /s/ R. Breck Denny
   -----------------------------               --------------------------------
         VICE PRESIDENT                          VICE PRESIDENT

JAMES H. DREW CORPORATION                   MEDUSA MINERALS COMPANY
                                             (FORMERLY THE THOMASVILLE STONE
                                              AND LIME COMPANY)

BY:  /s/ R. Breck Denny                     BY:  /s/ R. Breck Denny
   -----------------------------               --------------------------------
         VICE PRESIDENT                         VICE PRESIDENT

MEDUSA AGGREGATES COMPANY                   MEDUSA PORTLAND CEMENT COMPANY


BY: /s/ R. Breck Denny                      BY: /s/ R. Breck Denny
   -----------------------------               --------------------------------
         VICE PRESIDENT                                 VICE PRESIDENT

MEDUSA AGGREGATES LLC


BY:  /s/ R. Breck Denny
   -----------------------------               
         VICE PRESIDENT


<PAGE>   112
[LETTERHEAD]                MEDUSA  CORPORATION
             LEE AND MONTICELLO    CLEVELAND HEIGHTS, OHIO 44118    216/371-4000
JOHN P. SIEGFRIED                                               FAX 216/371-2912
VICE PRESIDENT, SECRETARY
AND GENERAL COUNSEL                                               MAIL ADDRESS
                                                                 P.O. BOX 5668
                                                                CLEVELAND, 44101
                                  EXHIBIT A

                                December 16, 1996


 To each of the Banks and the Agent
         party to the Credit Agreement
         referred to below
 c/o KeyBank National Association
 Key Center
 127 Public Square
 Cleveland, Ohio 44114

         Re:    U.S. $65,000,000 Credit Agreement 
                with Medusa Corporation
                -----------------------------------

 Ladies and Gentlemen:

        This opinion is furnished to you pursuant to section 4(vi) of
 Amendment No. 1 to Amended and Restated Revolving Credit Agreement,
 dated as of December 16, 1996 (the "AMENDMENT"), among Medusa
 Corporation (the "BORROWER"), the Banks parties thereto and KeyBank
 National Association (as successor to Society National Bank), as Agent
 for said Banks. Terms defined in the Amendment or in the Credit
 Agreement referred to in the Amendment are, unless otherwise defined
 herein, used herein as therein defined.

         I am a Vice President and the General Counsel and Secretary of
 the Borrower and have acted as counsel for the Borrower in connection
 with the preparation, execution and delivery of the Credit Agreement and
 the Amendment.

         In that connection, I have examined:

                  (1) The Credit Agreement and the Amendment.

                  (2) The Promissory Notes (the "NOTES") delivered by the
         Borrower to the Banks pursuant to the Amendment.

                  (3) The Articles of Incorporation of the Borrower and all
         amendments thereto (the "CHARTER").

                  (4) The Code of Regulations of the Borrower and all amendments
         thereto (the "CODE OF REGULATIONS").

<PAGE>   113

                  (5) A certificate of the Secretary of State of the State of
         Ohio, dated January 19 , 1993, attesting to the continued corporate
         existence and good standing of the Borrower in that State.

I have also examined the originals, or copies certified to my satisfaction, of
the documents referred to in the last sentence of section 4.01(g) of the Credit
Agreement (the "RESTRICTIVE AGREEMENTS"). In addition, I have examined the
originals, or copies certified to my satisfaction, of such other corporate
records of the Borrower, certificates of public officials and of officers of the
Borrower, and agreements, instruments and other documents, as I have deemed
necessary as a basis for the opinions expressed below. As to questions of fact
material to such opinions, I have, when relevant facts were not independently
established by me, relied upon certificates of the Borrower or its officers or
of public officials. I have assumed the due execution and delivery, pursuant to
due authorization, of the Credit Agreement and the Amendment by the Banks and
the Agent.

         I am qualified to practice law in the State of Ohio and do not purport
to be an expert on any laws other than the laws of the State of Ohio and the
Federal laws of the United States.

         Based upon the foregoing and upon such investigation as I have deemed
necessary, I am of the following opinion:

         1. The Borrower is a corporation duly organized, validly existing and
in good standing under the laws of the State of Ohio.

         2. The execution, delivery and performance by the Borrower of the
Credit Agreement, the Amendment and the Notes are within the Borrower's 
corporate powers, have been duly authorized by all necessary corporate  action,
and do not contravene (i) the Charter or the Code of Regulations, (ii) any
law, rule or regulation applicable to the Borrower (including, without
limitation, Regulation X of the Board of Governors of the Federal Reserve
System), or (iii) any contractual or legal restriction contained in any
Restrictive Agreement or, to the best of my knowledge, contained in any other
similar document.

         3 . The Credit Agreement, the Amendment and the Notes have been duly
executed and delivered on behalf of the Borrower. The Credit Agreement (as
amended by the Amendment) and the Notes each constitute a valid and binding
agreement or obligation of the Borrower enforceable against the Borrower in
accordance with their terms.

        4. No consent, approval or authorization of, or registration, filing or
declaration with, any Governmental Body is required on the part of the Borrower
for the valid execution and delivery of the Credit Agreement or the Amendment or
the consummation of the transactions contemplated thereby, including the
issuance and delivery of the Notes, or for the fulfillment of, or compliance by
the Borrower with, the terms and provisions of the Credit Agreement (as amended
by the Amendment) and the Notes.

         5. There are no pending or overtly threatened actions or proceedings
against the Borrower or any of its Subsidiaries before any court, governmental
agency or arbitrator which purport to affect the legality, validity, binding
effect or enforceability of the Credit Agreement or the Amendment or any of the
Notes or which might result in a Material Adverse Change in the Business or
Condition of the Borrower or of the Borrower and its Subsidiaries taken as a
whole.

                                      2
<PAGE>   114
         6. The transactions contemplated by the Credit Agreement (as amended by
the Amendment) will not result in a violation of Regulation U or Regulation X of
the Board of Governors of the Federal Reserve System.

         7. The Borrower is not an "investment company" or a Person directly or
indirectly "controlled" by or "acting on behalf of" an "investment company"
within the meaning of the Investment Company Act of 1940, as amended. The
Borrower is not a "holding company", or a "subsidiary company" of a "holding
company", or an "affiliate" of a "holding company" or of a "subsidiary company"
of a "holding company", as such terms are defined in the Public Utility Holding
Company Act of 1935, as amended.

                    The opinions set forth above are subject to the following
qualifications:

         (a) My opinion in the last sentence of paragraph 3 above is subject to
the effect of any applicable bankruptcy, insolvency, reorganization, moratorium
or similar law affecting creditors' rights generally.

         (b) My opinion in the last sentence of paragraph 3 above is subject to
the effect of general principles of equity, including (without limitation)
concepts of materiality, reasonableness, good faith and fair dealing (regardless
of whether considered in a proceeding in equity or at law).

         The opinions expressed herein are expressed solely to you and may not
be relied upon by any other persons for any reason, without the express written
consent of the undersigned.

                                      Very truly yours,


                                      /s/ John P. Siegfried


                                      John P. Siegfried


                                       3

<PAGE>   115
                               Medusa Corporation
                          U.S. $65,000,000 Amended and
                       Restated Revolving Credit Agreement


                             INCUMBENCY CERTIFICATE


         The undersigned, R. Breck Denny, of Medusa Corporation, an Ohio
corporation, hereby certifies that the following named persons, from January 1,
1996, to this day, have been and ARE the officers of the corporation holding the
offices set forth opposite their names, and that set opposite each name is the
true and genuine signature of that person.

<TABLE>
<CAPTION>
         Name              Title                                                Signature
         ----              -----                                                ---------
<S>                       <C>                                                <C>
                                                                              /s/ R. Breck Denny
R. B. Denny               Vice President-Finance and Treasurer               -----------------------------------       

                                                                               /s/ John P. Siegfried  
John P. Siegfried         Vice President, Secretary and General Counsel      -----------------------------------

<CAPTION>
   <S>                                                                       <C>
   IN WITNESS WHEREOF, I have hereunto set my hand this 16th day of December,
1996.

                                                                              /s/ John P. Siegfried
                                                                             ------------------------------------

<CAPTION>
         The undersigned, John P. Siegfried, hereby certifies that R. Breck
Denny is, on the date set forth above, the Vice President-Finance and Treasurer of
Medusa Corporation and that the foregoing signature of his is true and genuine.

                                                                              /s/ R. Breck Denny
                                                                            -----------------------------------




           Dated: December 16, 1996

</TABLE>

<PAGE>   116

                 CERTIFIED RESOLUTIONS OF THE BOARD OF DIRECTORS

         I DO HEREBY CERTIFY, That I am the duly elected and qualified Secretary
of Medusa Corporation, a corporation organized and existing under the laws of
the State of Ohio, and the keeper of the records and corporate seal of such
corporation; that the following is a true and correct copy of a certain
resolution duly adopted by the Board of Directors by unanimous vote at a
regularly scheduled meeting held on December 2, 1996, at which time a quorum was
always present, and that the resolution below has not been amended, revised,
modified or rescinded:

         "RESOLVED, that the Board hereby approves the terms and conditions of
         the revised Revolving Credit Agreement negotiated by the Company with
         four financial institutions in the face amount of $65.0 million,
         expiring December 21, 2001 , with interest rates, commitment fees and
         financial covenants substantially similar to the current Revolving
         Credit Agreement, along with a delegation of sufficient authority to
         the officers of the Company in order to give effect to this resolution,
         to enter into such agreements, and make such representations and
         covenants as are required in order to implement this resolution."

         IN WITNESS WHEREOF, I have hereunto affixed my name as Secretary and
have caused the corporate seal of such corporation to be hereto affixed this
Sixteenth day of December, 1996.

                                                      Respectfully submitted,

                                                       MEDUSA CORPORATION
(Corporate Seal)
                                                       By /s/ John P. Siegfried
                                                         ----------------------
                                         .               John P. Siegfried
                                                         Secretary
<PAGE>   117



                  (b) any change in the time, manner or place of payment of, or
         in any other term of all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the Credit
         Agreement or the Notes, including, without limitation, any increase in
         the Obligations resulting from the extension of additional credit to
         the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                 (d) any manner of application of collateral or proceeds        
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. Waiver. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. Subrogation. The Guarantor will not exercise any rights
which it may acquire by way of subrogation under this Guaranty, by any payment
made hereunder or otherwise, until all the Obligations and all other amounts
payable under this Guaranty shall have been paid in full and the Commitments
shall have expired or terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time prior to the later of (x) the
payment in full of the Obligations and all other amounts payable under this
Guaranty and (y) the expiration or termination of the Commitments, such amount
shall be held in trust for the benefit of the Agent and the Banks and shall
forthwith be paid to the Agent to be credited and applied upon the Obligations,
whether matured or unmatured, in accordance with the terms of the Credit
Agreement or to be held by the Agent as collateral security for any Obligations
thereafter exiting. If (i) the Guarantor shall make payment to the Agent or the
Banks of all or any part of the Obligations, (ii) all the Obligations and all
other amounts payable under this Guaranty shall be paid in full and (iii) the
Commitments shall have expired or terminated, the Agent and the Banks will, at
the Guarantor's request, execute and deliver to the Guarantor appropriate
documents, without recourse and without representation or warranty, necessary to
evidence the transfer by subrogation to the Guarantor of an interest in the
Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES.  THE GUARANTOR HEREBY
REPRESENTS AND WARRANTS AS FOLLOWS:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a corporation duly organized, validly existing and in good standing
         under the laws of the State of Michigan and has all requisite power and
         authority to own or hold under lease, to carry on its business as now
         conducted and proposed to be conducted, to enter into this Guaranty and
         to perform its obligations hereunder. The Guarantor has, by all
         necessary corporate action (all action of shareholders, if any,
         required therefor having been duly taken), duly authorized the
         execution and delivery of this Guaranty and the performance of its
         obligations under this Guaranty.


                                        2
<PAGE>   118

                  (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither the
         execution and delivery of this Guaranty nor the consummation of the
         transaction  contemplated hereby nor the performance of the terms and
         provisions thereof will result in any breach of, or constitute a
         default under, or result in (or require) the creation of any Lien in
         respect of any property of the Guarantor under, any agreement,
         indenture, mortgage, instrument, corporate charter (or corresponding
         document) or by-law to which the Guarantor is a party or by which the
         Guarantor or any of its properties may be bound or affected, or violate
         any existing law, governmental rule or regulation or any Order of any
         court, arbitrator or Governmental Body applicable to the Guarantor
         which could have a Material Adverse Effect on the Guarantor.

                  (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent, approval or
         authorization of, or registration, filing or declaration with, any
         Governmental Body is required on the part of the Guarantor for the
         valid execution and delivery of this Guaranty or for compliance by the
         Guarantor with the terms and provisions of this Guaranty.

                  (d) LITIGATION.  There are no actions, suits or proceedings
         pending or, to the knowledge of the Guarantor, threatened against or
         affecting the Guarantor in any court or before any arbitrator of any
         kind or before or by any Governmental Body, which question the validity
         of this Guaranty or any action taken or to be taken pursuant hereto.

                  (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty is a legal
         valid and binding obligation of the Guarantor enforceable against the
         Guarantor in accordance with its terms.

                 (f) FAMILIAR WITH BORROWER. The Guarantor is familiar with the
         finances and affairs of the Borrower and has, independently and
         without reliance upon the Agent or any Bank and based on such
         documents and information as it has deemed appropriate, made its own
         credit analysis and decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mail,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER, REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit

<PAGE>   119

Agreement to authorize the Agent to declare the Notes due and payable pursuant
to the provisions of said section 6.01, each Bank is hereby authorized at any
time and from time to time, to the fullest extent permitted by law, to set off
and apply any and all deposits (general or special, time or demand, provisional
or final) at any time held and other indebtedness at any time owing by such Bank
to or for the credit or the account of the Guarantor against any and all of the
obligations of the Guarantor now or hereafter existing under this Guaranty,
whether or not such Bank shall have made any demand under this Guaranty and
although such obligations may be contingent and unmatured. Each Bank agrees
promptly to notify the Guarantor after any such set-off and application made by
such Bank, PROVIDED that the failure to give such notice shall not affect the
validity of such set-off and application. The rights of each Bank under this
section are in addition to other rights and remedies (including, without
limitation, other rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY; ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of  the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11.  GOVERNING LAW.  This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                        MEDUSA PORTLAND CEMENT COMPANY



                                        By:  
                                           ----------------------------------
                                           Vice President


<PAGE>   120

                  (b) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Obligations, or any other
         amendment or waiver of or any consent to departure from the Credit
         Agreement or the Notes, including, without limitation, any increase in
         the Obligations resulting from the extension of additional credit to
         the Borrower or any of its Subsidiaries or otherwise;

                  (c) any taking, exchange, release or non-perfection of any
         collateral, or any taking, release or amendment or waiver of or consent
         to departure from any other guaranty, for all or any of the
         Obligations;

                  (d) any manner of application of collateral or proceeds
         thereof, to all or any of the Obligations, or any manner of sale or
         other disposition of any collateral for all or any of the Obligations
         or any other assets of the Borrower or any of its Subsidiaries;

                  (e) any change, restructuring or termination of the corporate
         structure or existence of the Borrower or any of its Subsidiaries; or

                  (f) any other circumstance which might otherwise constitute a
         defense available to, or a discharge of, the Borrower or a guarantor.

This Guaranty shall continue to be effective or be reinstated, as the case may
be, if at any time any payment of any of the Obligations is rescinded or must
otherwise be returned by the Agent or any Bank upon the insolvency, bankruptcy
or reorganization of the Borrower or otherwise, all as though such payment had
not been made.

         SECTION 3. WAIVER. The Guarantor hereby waives promptness, diligence,
notice of acceptance and any other notice with respect to any of the Obligations
and this Guaranty and any requirement that the Agent or any Bank protect,
secure, perfect or insure any security interest or lien or any property subject
thereto or exhaust any right or take any action against the Borrower or any
other person or entity or any collateral.

         SECTION 4. SUBROGATION. The Guarantor will not exercise any rights 
which it may acquire by way of subrogation under this Guaranty, by any
payment made hereunder or otherwise, until all the Obligations and all other
amounts payable under this Guaranty shall have been paid in full and the
Commitments shall have expired or terminated. If any amount shall be paid to
the Guarantor on account of such subrogation rights at any time prior to the
later of (x) the payment in full of the Obligations and all other amounts
payable under this Guaranty and (y) the expiration or termination of the
Commitments, such amount shall be held in trust for the benefit of the Agent
and the Banks and shall forthwith be paid to the Agent to be credited and
applied upon the Obligations, whether matured or unmatured, in accordance
with the terms of the Credit Agreement or to be held by the Agent as collateral
security for any Obligations thereafter existing. If (i) the Guarantor shall
make payment to the Agent or the Banks of all or any part of the Obligations,
(ii) all the Obligations and all other amounts payable under this Guaranty shall
be paid in full and (iii) the Commitments shall have expired or terminated, the
Agent and the Banks will, at the Guarantor's request, execute and deliver to the
Guarantor appropriate documents, without recourse and without representation or
warranty, necessary to evidence the transfer by subrogation to the Guarantor of
an interest in the Obligations resulting from such payment by the Guarantor.

         SECTION 5. REPRESENTATIONS AND WARRANTIES. The Guarantor hereby
represents and warrants as follows:

                  (a) ORGANIZATION AND AUTHORITY OF THE GUARANTOR. The Guarantor
         is a limited liability company duly organized, validly existing and in
         good standing under the laws of the Commonwealth of Pennsylvania and
         has all requisite power and authority to own or hold under lease, to
         carry on its business as now conducted and proposed to be conducted, to
         enter into this Guaranty and to perform its obligations hereunder. The
         Guarantor has, by all necessary corporate action (all action of
         shareholders, if any, required therefor having been duly taken), duly
         authorized the execution and delivery of this Guaranty and the
         performance of its obligations under this Guaranty.


                                        2


<PAGE>   121

                             (b) COMPLIANCE WITH OTHER INSTRUMENTS, ETC. Neither
                    the execution and delivery of this Guaranty nor the
                    consummation of the transactions contemplated hereby nor
                    the performance of the terms and provisions thereof will
                    result in any breach of, or constitute a default under, or
                    result in (or require) the creation of any Lien in respect
                    of any property of the Guarantor under, any agreement,
                    indenture, mortgage, instrument, corporate charter (or
                    corresponding document) or by-law to which the Guarantor is
                    a party or by which the Guarantor or any of its properties
                    may be bound or affected, or violate any existing law,
                    governmental rule or regulation or any Order of any court,
                    arbitrator or Governmental Body applicable to the Guarantor
                    which could have a Material Adverse Effect on the Guarantor.

                             (c) GOVERNMENTAL AUTHORIZATIONS, ETC. No consent,
                    approval or authorization of, or registration, filing or
                    declaration with, any Governmental Body is required on the
                    part of the Guarantor for the valid execution and delivery
                    of this Guaranty or for compliance by the Guarantor with the
                    terms and provisions of this Guaranty.

                             (d) LITIGATION. There are no actions, suits or
                    proceedings pending or, to the knowledge of the Guarantor,
                    threatened against or affecting the Guarantor in any court
                    or before any arbitrator of any kind or before or by any
                    Governmental Body, which question the validity of this
                    Guaranty or any action taken or to be taken pursuant hereto.

                             (e) VALIDITY OF THIS GUARANTY, ETC. This Guaranty 
                    is a legal, valid and binding obligation of the Guarantor 
                    enforceable against the Guarantor in accordance with its 
                    terms.

                             (f) FAMILIAR WITH BORROWER. The Guarantor is 
                    familiar with the finances and affairs of the Borrower      
                    and has, independently and without reliance upon the Agent
                    or any Bank and based on such documents and information as
                    it has deemed appropriate, made its own credit analysis and
                    decision to enter into this Guaranty.

         SECTION 6. AMENDMENTS, ETC. No amendment or waiver of any provision of
this Guaranty, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Agent and the Majority Banks, and then such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given,
PROVIDED, HOWEVER, that no amendment, waiver or consent shall, unless in writing
and signed by all the Banks, (a) limit the liability of the Guarantor hereunder,
(b) postpone any date fixed for payment hereunder, or (c) change the number of
Banks required to take any action hereunder.

         SECTION 7. ADDRESSES FOR NOTICES. All notices and other communications
provided for hereunder shall be in writing (including telecopier, telegraphic,
telex or cable communication) and mailed, telecopied, telegraphed, telexed,
cabled or delivered to it, if to the Guarantor, at its address c/o Medusa
Corporation, 3008 Monticello Boulevard, Cleveland Heights, Ohio 44119,
attention: Chief Financial Officer, and if to the Agent or any Bank, at its
address specified in the Credit Agreement, or, as to any party, at such other
address as shall be designated by such party in a written notice to each other
party. All such notices and other communications shall, when mailed, telecopied,
telegraphed, telexed or cabled, be effective when deposited in the mails,
telecopied, delivered to the telegraph company, confirmed by telex answerback or
delivered to the cable company, respectively.

         SECTION 8. NO WAIVER; REMEDIES. No failure on the part of the Agent or
any Bank to exercise, and no delay in exercising, any right hereunder shall
operate as a waiver thereof, nor shall any single or partial exercise of any
right hereunder preclude any other or further exercise thereof or the exercise
of any other right. The remedies herein provided are cumulative and not
exclusive of any remedies provided by law.

         SECTION 9. RIGHT OF SET-OFF. Upon (i) the occurrence and during the
continuance of any Event of Default and (ii) the making of the request or the
granting of the consent specified by section 6.01 of the Credit

                                       3
<PAGE>   122
 Agreement to authorize the Agent to declare the Notes due and payable pursuant
to the provisions of said section 6.01, each Bank is hereby authorized at any
time and from time to time, to the fullest extent permitted by law, to set off
and apply any and all deposits (general or special time or demand, provisional
or final) at any time held and other indebtedness at any time owing by such Bank
to or for the credit or the account of the Guarantor against any and all of the
obligations of the Guarantor now or hereafter existing under this Guaranty,
whether or not such Bank shall have made any demand under this Guaranty and
although such obligations may be contingent and unmatured. Each Bank agrees
promptly to notify the Guarantor after any such set-off and application made by
such Bank, PROVIDED that the failure to give such notice shall not affect the
validity of such set-off and application. The rights of each Bank under this
section are in addition to other rights and remedies (including, without
limitation, other rights of set-off) which such Bank may have.

         SECTION 10. CONTINUING GUARANTY, ASSIGNMENTS UNDER CREDIT AGREEMENT.
This Guaranty is a continuing guaranty and shall (i) remain in full force and
effect until the later of (x) the payment in full of the Obligations and all
other amounts payable under this Guaranty and (y) the expiration or termination
of the Commitments, (ii) be binding upon the Guarantor, its successors and
assigns, and (iii) inure to the benefit of, and be enforceable by, the Agent,
the Banks and their respective successors, transferees and assigns. Without
limiting the generality of the foregoing clause (iii), any Bank may assign or
otherwise transfer all or any portion of its rights and obligations under the
Credit Agreement (including, without limitation, all or any portion of its
Commitment, the Advances owing to it and any Note held by it) to any other
person or entity, and such other person or entity shall thereupon become vested
with all the benefits in respect thereof granted to such Bank herein or
otherwise, subject, however, to the provisions of Article VII (concerning the
Agent) of the Credit Agreement.

         SECTION 11.  GOVERNING LAW.  This Guaranty shall be governed by, and
construed in accordance with, the laws of the State of Ohio.

         SECTION 12. JURY TRIAL WAIVER. THE GUARANTOR, AND THE AGENT AND EACH
LENDER (BY THEIR ACCEPTANCE HEREOF), EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN THE AGENT OR ANY LENDER AND THE GUARANTOR ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
BETWEEN THEM IN CONNECTION WITH THIS GUARANTY OR ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE
TRANSACTIONS RELATED THERETO.


         IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.



                                         MEDUSA AGGREGATES LLC




                                          By 
                                            ----------------------------------
                                            Vice President


                                       4







<PAGE>   123
                                 PROMISSORY NOTE

U.S. $12,000,000                             Dated: December 16, 1996

         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of PNC BANK,
NATIONAL ASSOCIATION (the "BANK") for the account of its Applicable Lending
Office (as defined in the Credit Agreement referred to below) the principal sum
of U.S. TWELVE MILLION DOLLARS AND NO CENTS (Sl2,000,000.00), on the Termination
Date (as defined in the Credit Agreement), or, if less the aggregate principal
amount of the Advances (as defined below) made by the Bank to the Borrower
pursuant to the Credit Agreement outstanding on the Termination Date.

         The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

         Both principal and interest are payable in lawful money of the United
States of America to KeyBank National Association, as Agent, for the benefit of
the Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds.
Each Advance made by the Bank to the Borrower pursuant to the Credit Agreement,
and all payments made on account of the principal amount thereof, shall be
recorded by the Bank and, prior to any transfer hereof, endorsed on the grid
attached hereto which is part of this Promissory Note.

         This Promissory Note is one of the Notes referred to in, and is
entitled to the benefits of, the Amended and Restated Revolving Credit Agreement
dated as of January 27, 1993 and amended and restated as of December 15, 1995,
and as further amended by Amendment No. 1 thereto, dated as of December 16, 1996
(as so amended and restated and further amended and as hereinafter amended or
otherwise modified, the "CREDIT AGREEMENT"), among the Borrower, the Bank and
certain other banks parties thereto, and KeyBank National Association (as
successor by merger to Society National Bank), as Agent for the Bank and such
other banks. The Credit Agreement, among other things, (i) provides for the
making of advances (the "ADVANCES") by the Bank to the Borrower from time to
time in an aggregate amount not to exceed at any time outstanding the U.S.
dollar amount first above mentioned, the indebtedness of the Borrower resulting
from each such Advance being evidenced by this Promissory Note, and (ii)
contains provisions for acceleration of the maturity hereof upon the happening
of certain stated events and also for prepayments on account of principal hereof
prior to the maturity hereof upon the terms and conditions therein specified.

         This Promissory Note is issued in replacement of a Promissory Note
previously issued to the Bank under the Credit Agreement. Any Advances
outstanding under such prior Promissory Note on the date hereof shall continue
outstanding and be evidenced by this Promissory Note.


                                      MEDUSA CORPORATION


                                      By:/s/ R. Breck Denny
                                         ----------------------------
                                          Vice President-Finance

<PAGE>   124

                       ADVANCES AND PAYMENTS OF PRINCIPAL


<TABLE>
<CAPTION>
=======================================================================================================
                                             Amount of
                      Amount of              Principal Paid or      Unpaid Principal       Notation
Notation Date         Advance                Prepaid                Balance                Made By
-------------------------------------------------------------------------------------------------------
<S>                   <C>                    <C>                    <C>                    <C>

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

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=======================================================================================================
</TABLE>
<PAGE>   125
                                 PROMISSORY NOTE

U.S. $14,000,000                                        Dated: December 16, 1996

         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "Borrower"), HEREBY PROMISES TO PAY to the order of NBD BANK
(the "Bank") for the account of its Applicable Lending Office (as defined in the
Credit Agreement referred to below) the principal sum of U.S. FOURTEEN MILLION
DOLLARS AND NO CENTS ($14,000,000.00), on the Termination Date (as defined in
the Credit Agreement), or, if less, the aggregate principal amount of the
Advances (as defined below) made by the Bank to the Borrower pursuant to the
Credit Agreement outstanding on the Termination Date.

         The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates, and payable at such times, as are specified 
in the Credit Agreement.

         Both principal and interest are payable in lawful money of the United
States of America to KeyBank National Association, as Agent, for the benefit of 
the Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds.
Each Advance made by the Bank to the Borrower pursuant to the Credit Agreement,
and all payments made on account of the principal amount thereof, shall be
recorded by the Bank and, prior to any transfer hereof, endorsed on the grid
attached hereto which is part of this Promissory Note.

         This Promissory Note is one of the Notes referred to in, and is
entitled to the benefits of, the Amended and Restated Revolving Credit Agreement
dated as of January 27, 1993 and amended and restated as of December 15, 1995,
and as further amended by Amendment No. 1 thereto, dated as of December 16, 1996
(as so amended and restated and further amended and as hereinafter amended or
otherwise modified, the "Credit Agreement"), among the Borrower, the Bank and
certain other banks parties thereto, and KeyBank National Association (as
successor by merger to Society National Bank), as Agent for the Bank and such
other banks. The Credit Agreement, among other things, (i) provides for the
making of advances (the "Advances") by the Bank to the Borrower from time to
time in an aggregate amount not to exceed at any time outstanding the U.S.
dollar amount first above mentioned, the indebtedness of the Borrower resulting
from each such Advance being evidenced by this Promissory Note, and (ii)
contains provisions for acceleration of the maturity hereof upon the happening
of certain stated events and also for prepayments on account of principal
hereof prior to the maturity hereof upon the terms and conditions therein
specified.

         This Promissory Note is issued in replacement of a Promissory Note
previously issued to the Bank under the Credit Agreement. Any Advances 
outstanding under such prior Promissory Note on the date hereof shall continue
outstanding and be evidenced by this Promissory Note.


                                           MEDUSA CORPORATION

                                           By: /s/ R. Breck Denny
                                             ------------------------------
                                                Vice President-Finance
<PAGE>   126

                       ADVANCES AND PAYMENTS OF PRINCIPAL


<TABLE>
<CAPTION>
=======================================================================================================
                                             Amount of
                      Amount of              Principal Paid or      Unpaid Principal       Notation
Notation Date         Advance                Prepaid                Balance                Made By
-------------------------------------------------------------------------------------------------------
<S>                   <C>                    <C>                    <C>                    <C>

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

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-------------------------------------------------------------------------------------------------------

=======================================================================================================
</TABLE>
<PAGE>   127

                                 PROMISSORY NOTE


U.S. $14,000,000                                       Dated:- December 16, 1996



         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "Borrower"), HEREBY PROMISES TO PAY to the order of NATIONAL 
CITY BANK (the "Bank") for the account of its Applicable Lending Office (as
defined in the Credit Agreement referred to below) the principal sum of U.S.
FOURTEEN MILLION DOLLARS AND NO CENTS ($14,000,000.00), on the Termination Date
(as defined in the Credit Agreement), or, if less, the aggregate principal
amount of the Advances (as below) made by the Bank to the Borrower pursuant to
the Credit Agreement outstanding on the Termination Date.

         The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full, at such interest rates and payable at such times, as are specified in 
the Credit Agreement.

         Both principal and interest are payable in lawful money of the United
States of America to KeyBank National Association, as Agent, for the benefit of
the Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day funds.
Each Advance made by the Bank to the Borrower pursuant to the Credit Agreement, 
and all payments made on account of the principal amount thereof, shall be
recorded by the Bank and, prior to any transfer hereof, endorsed on the grid
attached hereto which is part of this Promissory Note.

         This Promissory Note is one of the Notes referred to in, and is
entitled to the benefits of, the Amended and Restated Revolving Credit Agreement
dated as of January 27, 1993 and amended and restated as of December 15, 1995,
and as further amended by Amendment No. 1 thereto, dated as of December 16, 1996
(as so amended and restated and further amended and as hereinafter amended or
otherwise modified, the "Credit Agreement"), among the Borrower, the Bank and
certain other banks parties thereto, and KeyBank National Association (as
successor by merger to Society National Bank), as Agent for the Bank and such
other banks. The Credit Agreement, among other things, (i) provides for the
making of advances (the "Advances") by the Bank to the Borrower from time to    
time in an aggregate amount not to exceed at any time outstanding the U.S.
dollar amount first above mentioned, the indebtedness of the Borrower resulting
from each such Advance being evidenced by this Promissory Note, and (ii)
contains provisions for acceleration of the maturity hereof upon the happening
of certain stated events and also for prepayments on account of principal
hereof prior to the maturity hereof upon the terms and conditions therein
specified.

         This Promissory Note is issued in replacement of a Promissory Note
previously issued to the Bank under the Credit Agreement. Any Advances
outstanding under such prior Promissory Note on the date hereof shall continue
outstanding and be evidenced by this Promissory Note.


                                 MEDUSA CORPORATION


                                 By: /s/ R. Breck Denny
                                    --------------------------------
                                        Vice President-Finance

<PAGE>   128


                       ADVANCES AND PAYMENTS OF PRINCIPAL


<TABLE>
<CAPTION>
=======================================================================================================
                                             Amount of
                      Amount of              Principal Paid or      Unpaid Principal       Notation
Notation Date         Advance                Prepaid                Balance                Made By
-------------------------------------------------------------------------------------------------------
<S>                   <C>                    <C>                    <C>                    <C>      

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

-------------------------------------------------------------------------------------------------------

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-------------------------------------------------------------------------------------------------------

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=======================================================================================================
</TABLE>
<PAGE>   129

                                 PROMISSORY NOTE



U.S. $25,000,000                                         Dated: December 16,1996



         FOR VALUE RECEIVED, the undersigned, MEDUSA CORPORATION, an Ohio
corporation (the "BORROWER"), HEREBY PROMISES TO PAY to the order of KEYBANK
NATIONAL ASSOCIATION (the "BANK") for the account of its Applicable Lending
Office (as defined in the Credit Agreement referred to below) the principal sum
of U.S. TWENTY-FIVE MILLION DOLLARS AND NO CENTS ($25,000,000.00), on the
Termination Date (as defined in the Credit Agreement), or, if less, the
aggregate principal amount of the Advances (as defined below) made by the Bank
to the Borrower pursuant to the Credit Agreement outstanding on the Termination
Date.

         The Borrower promises to pay interest on the unpaid principal amount of
each Advance from the date of such Advance until such principal amount is paid
in full at such interest rates, and payable at such times, as are specified in
the Credit Agreement.

         Both principal and interest are payable in lawful money of the United
States of America to KeyBank National Association, as Agent, for the benefit
of the Bank, at 127 Public Square, Cleveland, Ohio 44114-1306, in same day 
funds. Each Advance made by the Bank to the Borrower pursuant to the Credit
Agreement, and all payments made on account of the principal amount thereof,
shall be  recorded by the Bank and, prior to any transfer hereof, endorsed on
the grid attached hereto which is part of this Promissory Note.

                This Promissory Note is one of the Notes referred to in, and is
entitled to the benefits of, the Amended and Restated Revolving Credit  
Agreement dated as of January 27, 1993 and amended and restated as of December
15, 1995, and as further amended by Amendment No. 1 thereto, dated as of
December 16, 1996 (as so amended and restated and further amended and as
hereinafter amended or  otherwise modified, the "CREDIT AGREEMENT"), among the
Borrower, the Bank and certain other banks parties thereto, and KeyBank
National Association (as successor by merger to Society National Bank), as
Agent for the Bank and such other banks. The Credit Agreement, among other
things, (i) provides for the making of advances (the "ADVANCES") by the Bank to
the Borrower from time to time in an aggregate amount not to exceed at any time
outstanding the U.S. dollar amount first above mentioned, the indebtedness of
the Borrower resulting Erom each such Advance being evidenced by this
Promissory Note, and (ii) contains provisions for acceleration of the maturity
hereof upon the happening of certain stated events and also for prepayments on
account of principal hereof prior to the maturity hereof upon the terms and
conditions therein specified.

         This Promissory Note is issued in replacement of a Promissory Note
previously issued to the Bank under the Credit Agreement. Any Advances
outstanding under such prior Promissory Note on the date hereof shall continue
outstanding and be evidenced by this Promissory Note.


                                  MEDUSA CORPORATION


                                  By: /s/ R. Breck Denny
                                     ----------------------------------- 
                                        Vice President-Finance

<PAGE>   130

                       ADVANCES AND PAYMENTS OF PRINCIPAL


<TABLE>
<CAPTION>
=======================================================================================================
                                             Amount of
                      Amount of              Principal Paid or      Unpaid Principal       Notation
Notation Date         Advance                Prepaid                Balance                Made By
-------------------------------------------------------------------------------------------------------
<S>                   <C>                    <C>                    <C>                    <C>

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=======================================================================================================
</TABLE>

<PAGE>   131











-------------------------------------------------------------------------------
-------------------------------------------------------------------------------


                               MEDUSA CORPORATION
                                 AS THE BORROWER

                                       AND

                             THE BANKS NAMED HEREIN
                                    AS BANKS

                                       AND

                          KEYBANK NATIONAL ASSOCIATION
                                    AS AGENT





                          -----------------------------

                                 AMENDMENT NO. 2
                                   DATED AS OF
                                DECEMBER 17, 1997

                                       TO

                 AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT
                                   DATED AS OF
                                JANUARY 27, 1993
                         AND AMENDED AND RESTATED AS OF
                                DECEMBER 15, 1995
                          -----------------------------




-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
<PAGE>   132

                                 AMENDMENT NO. 2
                                       TO
                 AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

         THIS AMENDMENT, dated as of December 17, 1997 ("THIS AMENDMENT"), among
MEDUSA CORPORATION, an Ohio corporation (herein, together with its successors
and assigns, the "BORROWER"); the Banks party to the Credit Agreement referred
to below (the "BANKS"); and KEYBANK NATIONAL ASSOCIATION, a national banking
association which is successor by merger to Society National Bank, as Agent for
the Banks under such Credit Agreement:


         PRELIMINARY STATEMENTS:

         (1) The Borrower, the Banks named therein, and the the Agent entered
into the Amended and Restated Revolving Credit Agreement, dated as of January
27, 1993, and amended and restated as of December 15, 1995, and as further
amended by Amendment No. 1, dated as of December 16, 1996, to Amended and
Restated Credit Agreement (the "CREDIT AGREEMENT"; with the terms defined
therein, or the definitions of which are incorporated therein, being used herein
as so defined).

         (2) The Borrower, the Banks, and the Agent desire to amend certain of
the terms and provisions of the Credit Agreement in order, among other things,
to increase the aggregate amount of the Commitments of the Banks from
$65,000,000 to $180,000,000, to extend the existing Termination Date from
December 31, 2001 to December 31, 2002, and to make certain other modifications
to the terms and provisions thereof, all as more fully set forth below.

         NOW, THEREFORE, the parties hereby agree as follows:

         SECTION 1.        AMENDMENTS.

         1.1. REVISED COMMITMENT AMOUNTS. Effective on the Effective Date (as
hereinafter defined), (i) the respective Commitments of the Banks appearing
opposite their signatures to the Credit Agreement are changed to the amounts and
percentages indicated below:
<TABLE>
<CAPTION>

         Name of Bank                      Commitment Amount    Percentage
         ----------------------------      -----------------    ------------
<S>                                          <C>                  <C>     
         KeyBank National Association        $70,000,000          38.8889%
         National City Bank                  $38,000,000          21.1111%
         NBD Bank                            $38,000,000          21.1111%
         PNC Bank, National Association      $34,000,000          18.8889%
</TABLE>

; and (ii) the amount "$65,000,000" which appears on the cover page of the
Credit Agreement and as the Total of the Commitments on the page of the Credit
Agreement containing the signatures of the Banks is changed in each such
instance to "$180,000,000".

         1.2. EXTENSION OF MATURITY. Effective on the Effective Date, the date
"December 31, 2000" which appears in the definition of the term "TERMINATION
DATE" in section 1.01 of the Credit Agreement is changed to "December 31, 2002".


                                                         1

<PAGE>   133



         1.3. PRICING CHANGES. Effective on the Effective Date, the term
"Applicable Increment" which appears in section 2.06 of the Credit Agreement is
amended to read in its entirety as follows:

         The "APPLICABLE INCREMENT" for any Interest Period shall be equal to
         the percentage rate per annum shown in the Pricing Grid below in the
         column entitled Applicable Increment corresponding to the ratio of the
         Borrower's Consolidated Total Debt to the sum of the Borrower's
         Consolidated Total Debt plus Consolidated Net Worth as of the end of
         the Borrower's fiscal quarter ended most recently prior to such
         Interest Period as to which the Borrower shall have delivered to the
         Agent the financial statements for such quarter (or the fiscal year
         ended with such fiscal quarter) referred to in clause (a) or (b) of
         section 5.01, together with an Officer's Certificate setting forth in
         reasonable detail the amounts of Consolidated Total Debt and
         Consolidated Net Worth and the computation of such ratio.

<TABLE>
<CAPTION>


                                                   PRICING GRID
-------------------------------------------------------------------------------------------------------------
Ratio, expressed as a
percentage, of (i) Consolidated
Total Debt, to (ii) the sum of
Consolidated Total Debt and             Applicable Increment                    Commitment Fee Rate
Consolidated Net Worth                  (expressed in basis points)             (expressed in basis points)
-------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                      <C>
Less than or equal to 30.00%                             30.00                                   12.50
-------------------------------------------------------------------------------------------------------------
Greater than 30.00%, but less                            35.00                                   17.50
than or equal to 45.00%
-------------------------------------------------------------------------------------------------------------
Greater than 45.00%, but less                            45.00                                   25.00
than or equal to 55.00%
-------------------------------------------------------------------------------------------------------------
Greater than 55.00%                                      55.00                                   35.00
-------------------------------------------------------------------------------------------------------------
</TABLE>




         1.4. DEFINITION OF CONSOLIDATED NET WORTH. Effective on the Effective
Date, the entire definition of the term "Consolidated Tangible Net Worth" in
section 1.01 of the Credit Agreement is deleted and the following is substituted
therefor:

                  "CONSOLIDATED NET WORTH" means as at any date of
         determination, the amount under the caption "Total Shareholders'
         Equity" (or any similar caption) of the Borrower as shown on the most
         recent balance sheet of the Borrower prepared and delivered to the
         Banks pursuant to section 5.01.

         1.5. CONSOLIDATED TANGIBLE NET WORTH COVENANT. Effective on the
Effective Date, the covenant contained in section 5.10 of the Credit Agreement
shall be of no further force or effect.


                                        2

<PAGE>   134



          1.6. TOTAL DEBT TO CAPITAL COVENANT. Effective on the Effective Date,
section 5.14 of the Credit Agreement is amended to read in its entirety as
follows:

                  SECTION 5.14. CONSOLIDATED TOTAL DEBT TO CAPITAL. The Borrower
         will not permit the ratio of (i) Consolidated Total Debt, to (ii) the
         sum of Consolidated Total Debt and Consolidated Net Worth, expressed as
         a percentage, to exceed 65.00% at any time.

         1.7. REPRESENTATIONS AS TO CHANGES, ETC. (a) Effective on the Effective
Date, the phrase "Since December 31, 1995" which appears at the beginning of
section 4.01(e) of the Credit Agreement, is changed to "With the possible
exception of the effect of publicly announced charges taken in the fourth
quarter of 1997 related to environmental investigation, remediation and related
matters involving plants in Charlevoix, Michigan, and Wampum, Pennsylvania,
since December 31, 1996,".

         (b) Effective on the Effective Date, all references in section 4.01 (g)
[Compliance with Other Instruments, etc.] and in section 4.01(i) [Litigation] of
the Credit Agreement to "Material Adverse Change" or "Material Adverse Effect"
are changed to add thereafter the following parenthetical phrase: "(except for
the possible effect of the matters noted in section 4.01(a))".

         1.8. REPRESENTATIONS AS TO USE OF PROCEEDS; MARGIN REGULATIONS.
Effective on the Effective Date, section 4.01(n) of the Credit Agreement is
amended to read in its entirety as follows:

                  (n) USE OF PROCEEDS; MARGIN REGULATIONS. The proceeds of the
         Advances made hereunder will be used by the Borrower for general
         corporate purposes, including (without limitation) repurchases by the
         Borrower of shares of its outstanding Common Stock. Notwithstanding the
         foregoing, no proceeds of any Advance will be used, directly or
         indirectly, for the purpose of purchasing or carrying any margin stock
         in violation of the provisions of Regulation U of the Board of
         Governors of the Federal Reserve System. Neither the Borrower nor any
         of its Subsidiaries is engaged in the business of extending credit for
         the purpose of purchasing or carrying margin stock (as such term is
         defined in such Regulation U), and no proceeds of any Advance will be
         used to extend credit to others for the purpose of purchasing or
         carrying any margin stock. Following the application of the proceeds of
         any Advance, not more than 25% of the value of the assets (either of
         the Borrower only or of the Borrower and its Subsidiaries on a
         consolidated basis) will be margin stock. As used herein "margin stock"
         shall have the meaning ascribed to such term in such Regulation U.


         SECTION 2.        REPRESENTATIONS AND WARRANTIES.

         The Borrower represents and warrants that: (a) the Borrower has
delivered to the Agent and each Bank prior to the execution of this Amendment
true, correct and complete copies of the consolidated financial statements of
the Borrower and its consolidated subsidiaries for the fiscal year ended
December 31, 1996 and for the nine months ended September 30, 1997, such
consolidated financial statements have been prepared in accordance with
generally accepted accounting principles, consistently applied (except as noted
therein), and fairly present the consolidated financial condition of the
Borrower and its consolidated subsidiaries at such dates and the consolidated
results of their operations and cash flows for the periods then ended; (b) this
Amendment has been duly authorized by all necessary corporate action on the part
of the Borrower, has been duly executed and delivered by a duly authorized
officer or officers of the Borrower, and constitutes the valid and binding
agreement of the Borrower, enforceable against the Borrower in accordance with
its terms; (c) the representations and warranties of the Borrower contained

                                        3

<PAGE>   135



in the Credit Agreement, as amended hereby, are true and correct on and as of
the date hereof as though made on and as of the date hereof; (d) no condition or
event has occurred or exists which constitutes or which, after notice or lapse
of time or both, would constitute an Event of Default; and (e) the Borrower is
in full compliance with all covenants and agreements contained in the Credit
Agreement, as amended hereby.


         SECTION 3.        RATIFICATIONS.

         The terms and provisions set forth in this Amendment shall modify and
supersede all inconsistent terms and provisions set forth in the Credit
Agreement, and except as expressly modified and superseded by this Amendment,
the terms and provisions of the Credit Agreement are ratified and confirmed and
shall continue in full force and effect.


         SECTION 4.        BINDING EFFECT.

         This Amendment shall become effective on a date (the "EFFECTIVE DATE"),
on or before December 30, 1997, if and when the following conditions shall be
satisfied:

                  (a) AMENDMENT, ETC.: this Amendment shall have been executed
         by the Borrower and the Agent, and counterparts hereof as so executed
         shall have been delivered to the Agent; the Acknowledgment and Consent
         appended hereto shall have been executed by the Subsidiaries of the
         Borrower named therein, and counterparts thereof as so executed shall
         have been delivered to the Agent; the Agent shall have been notified by
         all of the Banks that such Banks have executed this Amendment (which
         notification may be by facsimile or other written confirmation of such
         execution);

                  (b) ROLLOVER OF ANY OUTSTANDING ADVANCES: if immediately prior
         to the Effective Date there are any Advances outstanding under the
         Credit Agreement, the Borrower shall have repaid such Advances on the
         Effective Date out of the proceeds of additional Advances obtained from
         the Banks on the Effective Date in accordance with the Commitments of
         the Banks as revised in this Amendment;

                  (c) CERTIFIED RESOLUTIONS OF THE BORROWER AND CERTAIN
         SUBSIDIARIES: certified copies of the resolutions of the Board of
         Directors of the Borrower and of each Subsidiary of the Borrower which
         has executed and delivered a Guaranty, approving the transactions
         contemplated by this Amendment, shall have been delivered to the Agent
         on or within five days prior to the Effective Date;

                  (d) INCUMBENCY CERTIFICATES OF THE BORROWER AND CERTAIN
         SUBSIDIARIES: a certificate of the Secretary or an Assistant Secretary
         of the Borrower and of each Subsidiary of the Borrower which has
         executed and delivered a Guaranty, certifying the names and true
         signatures of the officers of such person authorized to sign this
         Amendment and the other documents to which any such person is to be a
         party which are referred to herein, as applicable, shall have been
         delivered to the Agent on or within five days prior to the Effective
         Date;

                  (e) OPINION OF THE BORROWER'S COUNSEL: a favorable opinion of
         the General Counsel of the Borrower, satisfactory in form and substance
         to the Agent and the Banks and substantially

                                        4

<PAGE>   136



         in the form of Exhibit A hereto and as to such other matters as any
         Bank through the Agent may reasonably request, shall have been
         delivered to the Agent on or within five days prior to the Effective
         Date, in sufficient original copies for the Agent and the Banks;

                  (f) NEW NOTES: Notes of the Borrower to the order of the Banks
         shall have been duly executed and delivered to the Agent for delivery
         to the Banks in replacement of Notes previously issued to the Banks;
         and

                  (g) NOTICE FROM THE AGENT: the Agent shall have notified the
         Borrower and each Bank in writing that the conditions specified in the
         foregoing clauses have been satisfied;

and thereafter this Amendment shall be binding upon and inure to the benefit of
the Borrower, the Agent and each Bank and their respective permitted successors
and assigns, except that the Borrower shall not have the right to assign its
rights hereunder or any interest herein without the prior written consent of the
Banks.


         SECTION 5.        MISCELLANEOUS.

         5.1. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations
and warranties made in this Amendment shall survive the execution and delivery
of this Amendment, and no investigation by any Agent or any Bank or any
subsequent Advance shall affect the representations and warranties or the right
of the Agent or any Bank to rely upon them.

         5.2. REFERENCE TO CREDIT AGREEMENT. The Credit Agreement and any and
all other agreements, instruments or documentation now or hereafter executed and
delivered pursuant to the terms of the Credit Agreement as amended hereby, are
hereby amended so that any reference therein to the Credit Agreement shall mean
a reference to the Credit Agreement as amended hereby.

         5.3. EXPENSES. As provided in the Credit Agreement, but without
limiting any terms or provisions thereof, the Borrower agrees to pay on demand
all costs and expenses incurred by the Agent in connection with the preparation,
negotiation, and execution of this Amendment, including without limitation the
costs and fees of the Agent's special legal counsel, regardless of whether this
Amendment becomes effective in accordance with the terms hereof, and all costs
and expenses incurred by the Agent or any Bank in connection with the
enforcement or preservation of any rights under the Credit Agreement, as amended
hereby.

         5.4. SEVERABILITY. Any term or provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the term or provision so held to be invalid or unenforceable.

         5.5. APPLICABLE LAW. This Amendment shall be governed by and construed
in accordance with the laws of the State of Ohio.

         5.6. HEADINGS. The headings, captions and arrangements used in this
Amendment are for convenience only and shall not affect the interpretation of
this Amendment.

         5.7. ENTIRE AGREEMENT. This Amendment is specifically limited to the
matters expressly set forth herein. This Amendment and all other instruments,
agreements and documentation executed and

                                        5

<PAGE>   137



delivered in connection with this Amendment embody the final, entire agreement
among the parties hereto with respect to the subject matter hereof and supersede
any and all prior commitments, agreements, representations and understandings,
whether written or oral, relating to the matters covered by this Amendment, and
may not be contradicted or varied by evidence of prior, contemporaneous or
subsequent oral agreements or discussions of the parties hereto. There are no
oral agreements among the parties hereto relating to the subject matter hereof
or any other subject matter relating to the Credit Agreement.

         5.8. COUNTERPARTS. This Amendment may be executed by the parties hereto
separately in one or more counterparts, each of which when so executed shall be
deemed to be an original, but all of which when taken together shall constitute
one and the same agreement.


                [The balance of this page is intentionally blank;
                      the next page is the signature page.]


                                        6

<PAGE>   138





         IN WITNESS WHEREOF, this Amendment has been duly executed and delivered
as of the date first above written.


                                 MEDUSA CORPORATION


                                 BY: _________________________________
                                          VICE PRESIDENT-FINANCE



                                 KEYBANK NATIONAL ASSOCIATION,
                                     AS A BANK AND AS AGENT


                                 BY: __________________________________
                                      VICE PRESIDENT


                                 NATIONAL CITY BANK



                                 BY: __________________________________
                                     VICE PRESIDENT


                                 NBD BANK


                                 BY: __________________________________
                                      VICE PRESIDENT


                                PNC BANK, NATIONAL ASSOCIATION


                                 BY: __________________________________
                                     VICE PRESIDENT



                                        7

<PAGE>   139

                           ACKNOWLEDGMENT AND CONSENT

         Each of the undersigned is a party to a Guaranty (as such term is
defined in the Credit Agreement referred to in the Amendment No. 2 to Amended
and Restated Revolving Credit Agreement (the "AMENDMENT"), to which this
Acknowledgment and Consent is appended).

         For the avoidance of doubt, and without limitation of the intent and
effect of sections 2 and 3 of any Guaranty to which any of the undersigned is a
party, each of the undersigned hereby unconditionally and irrevocably (i)
acknowledges receipt of a copy of the Credit Agreement and the Amendment, and
(ii) consents to all of the terms and provisions of the Credit Agreement as
amended by the Amendment.

         Capitalized terms which are used herein without definition shall have
the respective meanings ascribed thereto in the Credit Agreement referred to
herein. This Acknowledgment and Consent is for the benefit of the Banks and the
Agent, any other person who is a third party beneficiary of a Guaranty, and
their respective successors and assigns. No term or provision of this
Acknowledgment and Consent may be modified or otherwise changed without the
prior written consent of the Agent, given as provided in the Credit Agreement.
This Acknowledgment and Consent shall be binding upon the successors and assigns
of each of the undersigned. This Acknowledgment and Consent may be executed by
any of the undersigned in separate counterparts, each of which shall be an
original and all of which together shall constitute one and the same instrument.

         IN WITNESS WHEREOF, each of the undersigned has duly executed and
delivered this Acknowledgment and Consent as of the date of the Amendment
referred to herein.





CANADIAN MEDUSA CEMENT LIMITED              MEDUSA-CITADEL, INC.


BY:                                         BY:       
   -----------------------------               --------------------------------
         VICE PRESIDENT                         VICE PRESIDENT

CEMENT TRANSIT COMPANY                      MEDUSA-CRESCENT, INC.


BY:                                         BY:
   -----------------------------               --------------------------------
         VICE PRESIDENT                          VICE PRESIDENT

JAMES H. DREW CORPORATION                   MEDUSA MINERALS COMPANY
                                             (FORMERLY THE THOMASVILLE STONE
                                              AND LIME COMPANY)

BY:                                         BY:
   -----------------------------               --------------------------------
         VICE PRESIDENT                         VICE PRESIDENT

MEDUSA AGGREGATES COMPANY                   MEDUSA PORTLAND CEMENT COMPANY


BY:                                         BY:
   -----------------------------               --------------------------------
         VICE PRESIDENT                                 VICE PRESIDENT

MEDUSA AGGREGATES LLC


BY:
   -----------------------------               
         VICE PRESIDENT
                                                         1
<PAGE>   140
                                    EXHIBIT A

                                [Effective Date]

To each of the Banks and the Agent
         party to the Credit Agreement
         referred to below
c/o KeyBank National Association
Key Center
127 Public Square
Cleveland, Ohio 44114

                  Re:      U.S.$180,000,000 Amended and Restated Credit
                           Agreement, as amended, with Medusa Corporation

Ladies and Gentlemen:

         This opinion is furnished to you pursuant to section 4(vi) of Amendment
No. 2 to Amended and Restated Revolving Credit Agreement, dated as of December
17, 1997 (the "Amendment"), among Medusa Corporation (the "Borrower"), the Banks
parties thereto, and KeyBank National Association (as successor to Society
National Bank), as Agent for said Banks. Terms defined in the Amendment or in
the Credit Agreement referred to in the Amendment are, unless otherwise defined
herein, used herein as therein defined.

         I am the General Counsel and Secretary of the Borrower and have acted
as counsel for the Borrower in connection with the preparation, execution and
delivery of the Credit Agreement and the Amendment.

         In that connection, I have examined:

                  (1) The Credit Agreement and the Amendment.

                  (2) The Promissory Notes (the "Notes") delivered by the
         Borrower to the Banks pursuant to the Amendment.

                  (3) The Articles of Incorporation of the Borrower and all
         amendments thereto (the "Charter").

                  (4) The Code of Regulations of the Borrower and all amendments
         thereto (the "CODE OF REGULATIONS").

                  (5) A certificate of the Secretary of State of the State of
         Ohio, dated a recent date, attesting to the continued corporate
         existence and good standing of the Borrower in that State.

I have also examined the originals, or copies certified to my satisfaction, of
the documents referred to in the last sentence of section 4.01(g) of the Credit
Agreement, as amended by the Amendment (the "RESTRICTIVE AGREEMENTS"). In
addition, I have examined the originals, or copies certified to my satisfaction,
of such other corporate records of the Borrower, certificates of public
officials and of officers of the Borrower, and agreements, instruments and other
documents, as I have deemed necessary as a basis


<PAGE>   141



for the opinions expressed below. As to questions of fact material to such
opinions, I have, when relevant facts were not independently established by me,
relied upon certificates of the Borrower or its officers or of public officials.
I have assumed the due execution and delivery, pursuant to due authorization, of
the Credit Agreement and the Amendment by the Banks and the Agent.

         I am qualified to practice law in the State of Ohio and do not purport
to be an expert on any laws other than the laws of the State of Ohio and the
Federal laws of the United States.

         Based upon the foregoing and upon such investigation as I have deemed
necessary, I am of the following opinion:

         1. The Borrower is a corporation duly organized, validly existing and
in good standing under the laws of the State of Ohio.

         2. The execution, delivery and performance by the Borrower of the
Credit Agreement, the Amendment and the Notes are within the Borrower's
corporate powers, have been duly authorized by all necessary corporate action,
and do not contravene (i) the Charter or the Code of Regulations, (ii) any law,
rule or regulation applicable to the Borrower (including, without limitation,
Regulation X of the Board of Governors of the Federal Reserve System), or (iii)
any contractual or legal restriction contained in any Restrictive Agreement or,
to the best of my knowledge, contained in any other similar document.

         3. The Credit Agreement, the Amendment and the Notes have been duly
executed and delivered on behalf of the Borrower. The Credit Agreement (as
amended by the Amendment) and the Notes each constitute a valid and binding
agreement or obligation of the Borrower enforceable against the Borrower in
accordance with their terms.

         4. No consent, approval or authorization of, or registration, filing or
declaration with, any Governmental Body is required on the part of the Borrower
for the valid execution and delivery of the Credit Agreement or the Amendment or
the consummation of the transactions contemplated thereby, including the
issuance and delivery of the Notes, or for the fulfillment of, or compliance by
the Borrower with, the terms and provisions of the Credit Agreement (as amended
by the Amendment) and the Notes.

         5. There are no pending or overtly threatened actions or proceedings
against the Borrower or any of its Subsidiaries before any court, governmental
agency or arbitrator which purport to affect the legality, validity, binding
effect or enforceability of the Credit Agreement or the Amendment or any of the
Notes or which might result in a Material Adverse Change (except for the
possible effect of the matters noted in section 4.01(a) of the Credit Agreement,
as amended) in the Business or Condition of the Borrower or of the Borrower and
its Subsidiaries taken as a whole.

         6. The transactions contemplated by the Credit Agreement (as amended by
the Amendment) will not result in a violation of Regulation U or Regulation X of
the Board of Governors of the Federal Reserve System.

         7. The Borrower is not an "investment company" or a Person directly or
indirectly "controlled" by or "acting on behalf of" an "investment company"
within the meaning of the Investment Company Act of 1940, as amended. The
Borrower is not a "holding company", or a "subsidiary company" of a "holding
company", or an "affiliate" of a "holding company" or of a "subsidiary company"
of a "holding company", as such terms are defined in the Public Utility Holding
Company Act of 1935, as amended.


                                      2

<PAGE>   142



         The opinions set forth above are subject to the following
qualifications:

         (a) My opinion in the last sentence of paragraph 3 above is subject to
the effect of any applicable bankruptcy, insolvency, reorganization, moratorium
or similar law affecting creditors' rights generally.

         (b) My opinion in the last sentence of paragraph 3 above is subject to
the effect of general principles of equity, including (without limitation)
concepts of materiality, reasonableness, good faith and fair dealing (regardless
of whether considered in a proceeding in equity or at law).

         The opinions expressed herein are expressed solely to you and may not
be relied upon by any other persons for any reason, without the express written
consent of the undersigned.

                                                              Very truly yours,



                                      3