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                                                                   EXHIBIT 10.13

                            CONVERTIBLE SUBORDINATED
                           PROMISSORY NOTE PAYABLE TO
                               COST CONTROLS, INC.

CONVERTIBLE SUBORDINATED PROMISSORY NOTE

$500,000.00                                                     January 15, 2002
                                                                 Cleveland, Ohio

      FOR VALUE RECEIVED, the undersigned, AMERICAN STONE INDUSTRIES, INC., a
Delaware corporation ("Maker"), promises to pay to the order of Cost Controls,
Inc. ("Payee"), the principal sum of Five Hundred Thousand and 00/100 Dollars
($500,000.00), together with interest thereon at a rate of six percent (6%) per
annum computed on a three hundred sixty-five (365) day year, in accordance with
the terms and subject to the conditions set forth below.

      1. Payment. The principal balance of this Note and any accrued but unpaid
interest thereon shall be due and payable on January 15, 2007. Maker shall pay
accrued interest under this Note on a quarterly basis on January 15, April 15,
July 15 and October 15 of each year during the period commencing on April 15,
2002 and continuing until the entire principal balance of this Note is paid in
full. Payments of both principal and interest under this Note shall be made by
Maker to Payee in lawful money of the United States of America to Payee's
address as set forth in Section 2 below.

      2. Address of Payee. Payments of principal of and interest on this Note
shall be made to Payee: Cost Controls, Inc., c/o, or at such other address as
Payee may designate in writing to Maker from time to time.

      3. Prepayment. Maker reserves the right to prepay at any time, without
premium or penalty, all or any portion of the indebtedness evidenced hereby.

      4. Conversion Feature. During the period commencing on the date hereof and
continuing until the entire principal balance of this Note is paid in full (the
"Conversion Period"), Payee shall have the right and option to convert (the
"Conversion Feature") the entire then outstanding principal balance of this Note
into Maker's common stock with a par value of $0.001 per share ("Common Stock").
Upon Payee's exercise of the Conversion Feature, the conversion price shall be
Five and 00/100 Dollars ($5.00) per share, which amount shall be subject to
adjustment as provided in Section 6 below (as such amount may be adjusted from
time to time, the "Conversion Price"). The number of shares issuable upon
Payee's exercise of the Conversion Feature shall be determined by dividing the
then outstanding principal balance of this Note by the Conversion Price, which
number shall be subject to adjustment as provided in Section 6 below. To
exercise the Conversion Feature, Payee must (a) complete, execute and deliver to
Maker a conversion notice in the form of EXHIBIT A attached hereto (the
"Conversion Notice") prior to the expiration of the Conversion Period and (b)
surrender the original of this Note to Maker at such time. Upon conversion, the
entire outstanding principal balance of this Note shall be deemed paid in full
by Maker. After delivery of the Conversion Notice, Payee's exercise of the
Conversion Feature shall be irrevocable except with the written consent of
Maker. The exercise of the Conversion Feature


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shall be effective as of thirty (30) days after Maker's receipt of the
Conversion Notice or as of such earlier date, not sooner than Maker's receipt of
the Conversion Notice, as determined by Maker in its sole discretion.

      5. Conditions to Exercise of Conversion Feature. The exercise of the
Conversion Feature and the issuance of Common Stock in connection therewith
shall, in all cases, be subject to each of the following conditions: (a) the
satisfaction of withholding tax or other withholding liabilities, (b) the
listing, registration or qualification of any to-be-issued shares upon any
securities exchange, the Nasdaq or other trading or quotation system or under
any federal or state law, (c) the consent or approval of any regulatory body
and/or (d) any requirement by Maker that Payee take any reasonable action to
meet all applicable requirements imposed by federal and state securities laws
including providing undertakings as to the investment intent of Payee, accepting
transfer restrictions on the Common Stock and providing opinions of counsel, in
form and substance acceptable to Maker, as to the availability of exemptions
from such requirements. Maker shall, in its sole discretion, determine whether
one or more of the foregoing conditions is necessary or desirable to be
satisfied in connection with the exercise of the Conversion Feature and prior to
the delivery of Common Stock pursuant to the exercise of the Conversion Feature.
The exercise of the Conversion Feature shall not be effective unless and until
such condition(s) have been satisfied or Maker has, in its sole discretion,
waived such conditions in writing.

      6. Adjustments. The Conversion Price and the number of shares of Common
Stock issuable upon exercise of the Conversion Feature shall be subject to
adjustment from time to time as provided below.

            (a) Stock Dividends, Splits and Reclassifications.

                  (1) In General. The following events are hereinafter referred
            to as "Adjustment Events": (i) Maker pays a dividend with respect to
            its capital stock in shares of Common Stock; (ii) Maker subdivides
            its outstanding shares of Common Stock; (iii) Maker combines its
            outstanding shares of Common Stock into a smaller number of shares
            of any class of Common Stock; or (iv) Maker issues any shares of its
            capital stock in a reclassification of Common Stock (including any
            such reclassification in connection with a merger, consolidation or
            other business combination in which Maker is the surviving entity).
            If an Adjustment Event occurs, the number of shares of Common Stock
            issuable upon exercise of the Conversion Feature immediately prior
            to the record date for such Adjustment Event shall be adjusted so
            that Payee shall thereafter be entitled to receive the number of
            shares of Common Stock that Payee would have owned, or would have
            been entitled to receive, after the happening of such Adjustment
            Event if the Conversion Feature had been exercised immediately prior
            to the happening of such Adjustment Event or any record date with
            respect thereto. An adjustment made pursuant to this Section 6(a)(1)
            shall become effective immediately after the effective date of such
            Adjustment Event retroactive to the record date, if any, for such
            Adjustment Event.

                  (2) Adjustment of the Conversion Price. Whenever the number of
            shares of Common Stock issuable upon exercise of the Conversion
            Feature is adjusted pursuant to Section 6(a)(1) above, the
            Conversion Price for each share of Common Stock payable upon
            conversion shall be adjusted by multiplying the


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            Conversion Price immediately prior to such adjustment by a fraction,
            the numerator of which shall be the number of shares of Common Stock
            issuable upon conversion immediately prior to such adjustment, and
            the denominator of which shall be the number of shares of the Common
            Stock so issuable immediately thereafter.

            (b) When No Adjustment Required. No adjustment need be made for any
      of the following:

                  (1) transactions referred to in Section 6(a)(1) above, if
            Payee is to participate in the transaction on a basis and with
            notice that the board of directors of Maker determines to be fair
            and appropriate in light of the basis and notice on which holders of
            Common Stock participate in the transaction;

                  (2) rights to purchase Common Stock pursuant to a plan of
            Maker for reinvestment of dividends or interest;

                  (3) a change in the par value or a change to no par value of
            the Common Stock;

                  (4) unless such adjustment would require an increase or
            decrease of at least one percent (1%) in the number of shares of
            Common Stock issuable upon exercise of the Conversion Feature (all
            such calculations shall be made to the nearest full share); or

                  (5) if the amount of such adjustment would be less than $0.05
            per share of Common Stock.

            (c) Consolidation or Merger. In the case of any consolidation or
      merger of Maker with or into another entity (other than a consolidation or
      merger in which Maker is the continuing entity and which does not result
      in any reclassification or change of outstanding shares of Common Stock),
      Maker shall execute and deliver to Payee an agreement supplemental hereto,
      providing that Payee shall have the right thereafter, during the
      Conversion Period, to convert this Note into the kind and amount of shares
      of stock, other securities, cash and other property receivable upon such
      consolidation or merger. Such supplemental agreement shall provide for
      adjustments which shall be as nearly equivalent as may be practicable to
      the adjustments provided in this Section 6. The rights of Payee under such
      supplemental agreement shall replace entirely all rights of Payee under
      this Section 6.

      7. Subordination.

            (a) Senior Indebtedness. Maker covenants and agrees, and Payee, for
      itself and for each subsequent holder of this Note, by its acceptance
      hereof likewise covenants and agrees, that the indebtedness represented by
      this Note and the payment of the principal of and interest on this Note is
      hereby expressly subordinated and junior in right of payment to the prior
      payment in full of the principal of (and premium, if any) and interest on
      any of the following (collectively, the "Senior Indebtedness"):


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                  (1) all indebtedness of Maker (including indebtedness of
            others guaranteed by Maker) other than under this Note, whether
            outstanding on the date of this Note or thereafter created, incurred
            or assumed, which is (A) for money borrowed or (B) evidenced by a
            note or similar instrument given in connection with the acquisition
            of any businesses, properties or assets of any kind;

                  (2) obligations of Maker as lessee under leases required to be
            capitalized on the balance sheet of the lessee under generally
            accepted accounting principles and leases of property or assets made
            as part of any sale and lease-back transaction to which Maker is a
            party;

                  (3) all borrowings under any lines of credit, revolving credit
            agreements or promissory notes from a bank or other financial
            institution (including any letters of credit, performance bonds and
            other credit facilities under such borrowing arrangements), and any
            amendments, modifications, renewals or extensions of any of the
            foregoing;

                  (4) any amounts payable in respect of any interest rate
            exchange agreement, currency exchange agreement or similar
            agreement; and

                  (5) amendments, renewals, extensions, modifications and
            refundings of any such indebtedness or obligation, unless in any
            case the instrument creating or evidencing any such indebtedness or
            obligation or pursuant to which the same is outstanding provides
            that such indebtedness or obligation is not superior in right of
            payment to this Note.

            (b) Permitted Payments. Notwithstanding any provision in this Note
      to the contrary, Payee, and each subsequent holder of this Note, by its
      acceptance hereof, acknowledges and agrees that it is entitled to receive
      payments of principal of or interest on this Note only to the extent that
      such payments (1) are made in accordance with the original tenor of this
      Note at the times, in the amounts and otherwise in strict conformity with
      the provisions of Section 1 and Section 7(a) above and (2) are not
      otherwise prohibited under the remaining provisions of this Section 7.

            (c) Insolvency/Bankruptcy. In the event of any insolvency or
      bankruptcy proceedings, and any receivership, liquidation, reorganization
      or other similar proceedings in connection therewith, relative to Maker or
      to the property of Maker, and in the event of any proceedings for
      voluntary liquidation, dissolution or other winding-up of Maker, whether
      or not involving insolvency or bankruptcy, the holders of the Senior
      Indebtedness shall first be entitled to receive payment in full of all of
      the Senior Indebtedness before any holder of this Note is entitled to
      receive any payment on account of the principal of or interest on the
      indebtedness evidenced by this Note.

            (d) Maturity of Senior Indebtedness. Upon the maturity of any Senior
      Indebtedness by lapse of time, acceleration or otherwise, all such
      maturing Senior Indebtedness shall first be paid in full before any
      payment is made on account of the principal of or interest on this Note.

            (e) Loan Covenants. Payments, whether on account of interest or
      principal, may be prohibited, or otherwise restricted or conditioned by
      any holder of the Senior Indebtedness, upon delivery of notice to Payee or
      other holder hereof, at any time if (1) Maker, at such time, is in default
      under such Senior Indebtedness or (2) the effect of making such payment
      would be to cause


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      Maker to be in default under the provisions of any loan agreement with any
      holder of the Senior Indebtedness.

            (f) Subordination Agreement. To the extent that any holder of the
      Senior Indebtedness requests that Payee or any other holder of this Note
      execute a separate agreement respecting the terms and conditions of
      subordination relative to the indebtedness evidenced hereby (any such
      agreement being hereinafter referred to as a "Subordination Agreement"),
      Payee or such other holder shall, so long as the same is not materially
      inconsistent with the terms of subordination herein set forth or the
      intent hereof, execute such Subordination Agreement and, to the extent so
      executed by Payee or other holder hereof, the terms and conditions of such
      Subordination Agreement shall govern in the event of any conflict with the
      terms hereof.

            (g) Payments in Contravention. In the event that any direct or
      indirect payment or distribution shall be received by the holder of this
      Note in contravention of the provisions of this Section 7 or a
      Subordination Agreement, if any, then, and in any such event, such payment
      or distribution shall be held in trust for the benefit of, and shall be
      paid over and delivered to, the holders of the Senior Indebtedness (as
      their respective interests may appear) for application to the payment of
      all Senior Indebtedness.

            (h) Continuing Terms of Subordination/Future Lenders. The
      indebtedness evidenced hereby shall continue to be subordinated to any and
      all future indebtedness, including renewals, extensions and refundings
      thereof, of Maker to any person or entity which is or may become a holder
      of any Senior Indebtedness unless the instrument creating or evidencing
      the same and pursuant to which the same is outstanding provides that such
      indebtedness or such renewal, extension or refunding thereof is not
      superior in right to payment of this Note.

      8. Acceleration. The entire unpaid principal balance of this Note,
together with all accrued and unpaid interest thereon, shall become due and
payable forthwith without presentation, protest, demand or notice of any kind,
all of the foregoing being expressly waived, upon the occurrence of any one or
more of the following events of default:

            (a) the failure by Maker to make any payment required hereunder
      within thirty (30) days after the due date thereof;

            (b) the failure or neglect of Maker to perform, keep or observe any
      other term, provision, condition, covenant, warranty or representation
      that is required to be performed, kept or observed by Maker under this
      Note, if Maker fails to cure such failure or neglect within thirty (30)
      days after Maker's receipt of written notice thereof delivered by Payee.

            (c) the commencement by or against Maker of any proceeding for
      reorganization, liquidation, dissolution or receivership, or the filing of
      any voluntary or involuntary petition in bankruptcy by or against Maker or
      the commencement of any proceeding under any other present or future
      federal or state insolvency or other law for the relief from, or
      adjustment of, any indebtedness, to the extent that any of the foregoing
      are not dismissed within ninety (90) days after the filing thereof;

            (d) the dissolution or termination of existence of Maker; or

            (e) the sale of all, or substantially all, of the assets of Maker.


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      9. Representations, Warranties and Covenants of Payee. Payee, for itself
and for each subsequent holder of this Note, by its acceptance hereof
represents, warrants and covenants to Maker, that:

            (a) Payee is acquiring this Note for his own account, for
      investment, and not for distribution or resale, and will make no transfer
      of this Note except in compliance with applicable federal and state
      securities laws;

            (b) Payee can bear the economic risk of investment in this Note,
      including a total loss of Payee's investment;

            (c) Payee is experienced in business and financial matters and is
      capable of (1) evaluating the merits and risks of an investment in this
      Note, (2) making an informed investment decision regarding this Note and
      (3) protecting Payee's interests in connection therewith; and

            (d) Payee is an "Accredited Investor," as such term is defined in
      Rule 501 of Regulation D promulgated by the Securities and Exchange
      Commission pursuant to the Securities Act of 1933, as amended.

      10. Governing Law. This Note shall be construed under and governed by the
laws of the State of Ohio, without giving effect to principles of conflicts of
laws contained therein.

      11. Notices. Any notice to Maker required or permitted hereunder shall be
deemed to have been effectively delivered (a) upon transmission if sent via
facsimile, with a copy sent via overnight courier, provided that such overnight
delivery is received, (b) when received if in writing and served by personal
delivery to Maker or (c) three business days after deposit in the United States
mail if sent by registered or certified mail with return receipt requested,
postage prepaid, to Maker. Such notices and other communications shall be sent
to Maker at the address or facsimile number below or at such other address or
facsimile number as Maker may designate in writing to Payee from time to time:

             American Stone Industries, Inc.
             Attn: James M. Rallo
             8705 Quarry Road
             Amherst, Ohio 44001
             Facsimile: (440) 986-4531

      12. Successors. This Note shall be binding upon the successors and assigns
of Maker and shall inure to the benefit of the heirs, successors and assigns of
Payee; provided, however, that Payee may not sell, transfer, hypothecate or
assign his interest hereunder, in whole or in part, directly or indirectly, by
operation of law or otherwise without the prior written consent of Maker, which
consent may be withheld in Maker's sole and absolute discretion, and any
attempted sale, transfer, hypothecation or assignment in the absence of such
consent shall be void and of no effect.

      13. Partial Invalidity. If any term or provision of this Note or the
application thereof to any person, firm or corporation or any circumstance,
shall be invalid or unenforceable, the remainder of this Note, or the
application of such term or provision to any person, firm or corporation or any
circumstance, other than those as to which it is held invalid, shall both be
unaffected thereby and each term or provision of this Note shall be valid and be
enforced to the fullest extent permitted by law.


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      14. Captions. The captions and section numbers appearing in this Note are
inserted only as a matter of convenience; they do not define, limit, construe or
describe the scope or intent of the provisions of this Note.

      15. Consent. Maker and Payee hereby irrevocably and unconditionally
consent to submit to the exclusive jurisdiction of the courts of the State of
Ohio and of the United States of America located in the City of Cleveland, Ohio,
for any actions, suits or proceedings arising out of or relating to this Note
and the transactions contemplated hereby (and Maker and Payee agree not to
commence any action, suit or proceeding relating thereto except in such courts),
and further agree that service of any process, summons, notice or document by
U.S. certified or registered mail, return receipt requested, to the addresses
set forth in Section 11 or Section 2 above shall be effective service of process
for any action, suit or proceeding brought against Maker or Payee in any such
court. Maker and Payee hereby irrevocably and unconditionally waive any
objection to the laying of venue of any action, suit or proceeding arising out
of this Note, or the transactions contemplated hereby, in the courts of the
State of Ohio or of the United States of America located in the City of
Cleveland, Ohio, and hereby further irrevocably and unconditionally waive and
agree not to plead or claim in any such court that any such action, suit or
proceeding brought in any such court has been brought in an inconvenient forum.

      16. Joint Preparation. This Note shall be deemed to have been prepared
jointly by Maker and Payee, and any uncertainty or ambiguity existing herein
shall not be interpreted against either party, but shall be interpreted
according to the rules for the interpretation of arm's length agreements.

      17. Third Parties. Nothing herein, express or implied, is intended to be
or shall be construed to confer upon or give any person other than the parties
hereto and their successors or assigns, any rights or remedies under or by
reason of this Note.

      18. Waiver of Jury Trial. MAKER AND PAYEE HEREBY VOLUNTARILY, IRREVOCABLY
AND UNCONDITIONALLY WAIVE ANY RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY
DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT, OR OTHERWISE, BETWEEN MAKER AND
PAYEE ARISING OUT OF, IN CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED BETWEEN MAKER AND PAYEE IN CONNECTION WITH THIS NOTE OR
ANY OTHER AGREEMENT OR DOCUMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR
THEREWITH OR THE TRANSACTIONS RELATED HERETO OR THERETO.

      IN WITNESS WHEREOF, Maker has executed this Note as of the day and year
first written above.

                                        AMERICAN STONE INDUSTRIES, INC.


                                                By: /s/ James M. Rallo
                                                   -----------------------------
                                                Name: James M. Rallo
                                                Title: President


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                                    EXHIBIT A
                                       TO
                    CONVERTIBLE SUBORDINATED PROMISSORY NOTE

                            FORM OF CONVERSION NOTICE

                    NOTICE OF EXERCISE OF CONVERSION FEATURE
                                      UNDER
              $ 500,000.00 CONVERTIBLE SUBORDINATED PROMISSORY NOTE

To:   American Stone Industries, Inc. ("Maker")

From: Cost Controls, Inc.

Date: _____________, _____

      Pursuant to the terms and conditions of that certain $500,000.00
Convertible Subordinated Promissory Note dated February ____, 2002, as issued by
Maker and made payable to the order of Payee (the "Note"), the undersigned
hereby exercises the right to convert the entire outstanding principal balance
due and payable under the Note into Maker's common stock in accordance with the
terms of the Note (the "Common Stock").

      The undersigned hereby represents, warrants, and covenants to Maker that:

      (a) The undersigned is acquiring the Common Stock for his own account, for
investment, and not for distribution or resale, and the undersigned will make no
transfer of the Common Stock except in compliance with applicable federal and
state securities laws.

      (b) The undersigned can bear the economic risk of the investment in the
Common Stock resulting from this exercise of the "Conversion Feature" (as such
term is defined in the Note), including a total loss of the undersigned's
investment.

      (c) The undersigned is experienced in business and financial matters and
is capable of (i) evaluating the merits and risks of an investment in the Common
Stock; (ii) making an informed investment decision regarding exercise of the
Conversion Feature; and (iii) protecting the undersigned's interests in
connection therewith.

      (d) The undersigned is an "Accredited Investor," as such term is defined
in Rule 501 of Regulation D promulgated by the Securities and Exchange
Commission pursuant to the Securities Act of 1933, as amended.

      The undersigned acknowledges that issuance of the Common Stock pursuant to
the Note is subject to further conditions set forth in the Note.


Date: _____________, _____              ________________________________________
                                        Cost Controls, Inc.


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