Document:

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                                                                EXHIBIT 4.2

                            SUPPLEMENTAL INDENTURE

               Supplemental Indenture (this "Supplemental Indenture"), dated as
               of December 1, 2000, among BMAC SERVICES CO., INC., a Delaware
               corporation (the "New Guarantor"), BETTER MINERALS & AGGREGATES
               COMPANY, a Delaware corporation ("Better Minerals"), U.S. SILICA
               COMPANY, a Delaware corporation, BETTER MATERIALS CORPORATION, a
               Pennsylvania corporation, GEORGE F. PETTINOS, INC., a Delaware
               corporation, OTTAWA SILICA COMPANY, a Delaware corporation, THE
               FULTON LAND AND TIMBER COMPANY, a Pennsylvania corporation,
               PENNSYLVANIA GLASS SAND CORPORATION, a Delaware corporation,
               CHIPPEWA FARMS CORPORATION, a Pennsylvania corporation, BMC
               TRUCKING, INC., a Delaware corporation, STONE MATERIALS COMPANY,
               LLC, a Delaware limited liability company, COMMERCIAL STONE CO.,
               INC., a Pennsylvania corporation, and COMMERCIAL AGGREGATES
               TRANSPORTATION AND SALES, LLC, a Delaware limited liability
               company (collectively, the "Existing Guarantors"), and THE BANK
               OF NEW YORK, a New York banking corporation, as trustee under the
               indenture referred to below (the "Trustee").

                                  WITNESSETH:

          WHEREAS Better Minerals and the Existing Guarantors have heretofore
executed and delivered to the Trustee an Indenture (the "Indenture"), dated as
of October 1, 1999, providing for the issuance of an aggregate principal amount
of up to $150,000,000 of 13% Senior Subordinated Notes due 2009 (the
"Securities");

          WHEREAS Section 4.11 of the Indenture provides that under certain
circumstances Better Minerals is required to cause the New Guarantor to execute
and deliver to the Trustee a supplemental indenture pursuant to which the New
Guarantor shall unconditionally guarantee all of Better Minerals' obligations
under the Securities pursuant to a Note Guarantee on the terms and conditions
set forth herein; and

          WHEREAS pursuant to Section 9.01 of the Indenture, the Trustee, Better
Minerals and the Existing Guarantors are authorized to execute and deliver this
Supplemental Indenture without the consent of any holder of the Securities;
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          NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the New
Guarantor, Better Minerals, the Existing Guarantors and the Trustee mutually
covenant and agree for the equal and ratable benefit of the holders of the
Securities as follows:

          1. Agreement to Guarantee.  The New Guarantor hereby agrees, jointly
             -----------------------
and severally with all the Existing Guarantors, to unconditionally guarantee
Better Minerals' obligations under the Securities on the terms and subject to
the conditions set forth in Articles 11 and 12 of the Indenture and to be bound
by all other applicable provisions of the Indenture and the Securities.

          2. Ratification of Indenture; Supplemental Indentures Part of
             ----------------------------------------------------------
Indenture.  Except as expressly amended hereby, the Indenture is in all respects
----------
ratified and confirmed and all the terms, conditions and provisions thereof
shall remain in full force and effect.  This Supplemental Indenture shall form a
part of the Indenture for all purposes, and every holder of Securities
heretofore or hereafter authenticated and delivered shall be bound hereby.

          3. Governing Law.  THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY,
             --------------
AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

          4. Trustee Makes No Representation.  The Trustee makes no
             --------------------------------
representation as to the validity or sufficiency of this Supplemental Indenture.

          5. Counterparts.  The parties may sign any number of copies of this
             -------------
Supplemental Indenture.  Each signed copy shall be an original, but all of them
together represent the same agreement.

          6. Effect of Headings.  The Section headings herein are for
             -------------------
convenience only and shall not affect the construction thereof.

                                       2
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          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                                         BMAC SERVICES CO., INC.

                                         By:__________________________
                                            Name:
                                            Title:

                                         BETTER MINERALS & AGGREGATES COMPANY

                                         By:__________________________
                                            Name:
                                            Title:

                                         U.S. SILICA COMPANY

                                         By:__________________________
                                            Name:
                                            Title:

                                         BETTER MATERIALS CORPORATION

                                         By:__________________________
                                            Name:
                                            Title:

                                         GEORGE F. PETTINOS, INC.

                                         By:__________________________
                                            Name:
                                            Title:

                                       3
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                                         OTTAWA SILICA COMPANY

                                         By:___________________________
                                            Name:
                                            Title:

                                         THE FULTON LAND AND TIMBER COMPANY

                                         By:___________________________
                                            Name:
                                            Title:

                                         PENNSYLVANIA GLASS SAND CORPORATION

                                         By:___________________________
                                            Name:
                                            Title:

                                         CHIPPEWA FARMS CORPORATION

                                         By:___________________________
                                            Name:
                                            Title:

                                         BMC TRUCKING, INC.

                                         By:___________________________
                                            Name:
                                            Title:

                                         STONE MATERIALS COMPANY, LLC

                                         By:___________________________
                                            Name:
                                            Title:

                                       4
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                                         COMMERCIAL STONE CO., INC.

                                         By:___________________________
                                            Name:
                                            Title:

                                         COMMERCIAL AGGREGATES TRANSPORTATION
                                         AND SALES, LLC

                                         By:___________________________
                                            Name:
                                            Title:

THE BANK OF NEW YORK, as Trustee

By:________________________________
   Name:
   Title:

                                       5<PAGE>

                                                                   Exhibit 10.11

                             AMENDMENT NUMBER ONE

               (to Employment Agreement dated December 14, 1998)

         THIS AGREEMENT, made this _________ day of ________________, 2001, is
between Better Materials Corporation, a Pennsylvania corporation (hereinafter
"Company"), and Craig S. Cinalli (hereinafter "Executive").

         WHEREAS, the Company and the Executive are parties to an Employment
Agreement dated December 14, 1998, which expires on December 14, 2000; and,

         WHEREAS, the Company and the Executive desire to extend the Term of
Employment of the Executive and change some of the other terms of the Employment
Agreement;

         NOW, THEREFORE, the Company and the Executive agree as follows:

         1.   The Employment Agreement between the parties dated
              December 14, 1998, attached as Exhibit "A" (hereinafter
              "Agreement"), as amended by this Amendment Number One, is ratified
              and confirmed and shall remain in effect.

         2.   The last sentence of Paragraph 1 of the Agreement is amended to
              read as follows:

              The Executive shall not be required to have his primary place
              of employment more than 50 miles from his current place of
              employment.

         3.   Paragraph 2 of the Agreement is amended to read as follows:

              Term of Employment. The employment hereunder shall be for a term
              ------------------
              of two years beginning on December 14, 2000 and ending on the
              second anniversary thereof (the "Expiration Date"), unless earlier
              terminated pursuant to Paragraph 4 of this Agreement (the "Term of
              Employment").

         4.   Paragraphs 3(a), (b) and (d) of the Agreement are amended to read
              as follows:

              (a)   Salary. As compensation for services rendered hereunder, the
                    ------
                    Executive shall receive in the calendar year 2001 a minimum
                    Annual Salary of One Hundred Ninety Five Thousand Dollars
                    ($195,000.00), which salary shall be paid in accordance with
                    the Company's then prevailing payroll practices. The
                    Executive shall be eligible for merit increases in the
                    Annual Salary in accordance with the practice applicable to
                    other USSH senior executives.

              (b)   Restricted Stock. If (i) the Executive is terminated without
                    ----------------
                    cause pursuant to paragraph 4(d) of this Employment
                    Agreement, or (ii) the Company and the Executive fail to
                    enter into a new agreement with respect to the employment of
                    the Executive within ninety days after the Expiration Date,
                    and the Company or the Executive terminate the Executive's
                    employment with the Company, then, for purposes of the
                    Manager Repurchase Agreement dated as of March 17, 1999 (the
                    "Repurchase Agreement")
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                                                                     Page 2 of 3

                    between USS Holdings, Inc. and the Executive, a Termination
                    Event (as defined in the Stockholders Agreement dated
                    October 6, 1998) shall be deemed to occur not sooner than
                    December 14, 2001, which is the third anniversary of the
                    date of the Executive's initial employment with a Subsidiary
                    of the Corporation (as defined in the Repurchase Agreement).

           (d)      Other Benefits. The fringe benefits, perquisites and other
                    --------------
                    benefits of employment to be provided to the Executive shall
                    be equivalent to such benefits and perquisites as are
                    provided to other senior executives of USSH as amended from
                    time to time. The Executive shall be entitled to a company
                    automobile, which the Executive shall use for business
                    purposes only. The Executive shall be entitled to live at
                    the residence at Chippewa Farms owned by the Company rent
                    free during the term of this Agreement, provided, however,
                    that the rental value of residing in the residence rent free
                    realized by the Executive shall be imputed to the Executive
                    as income.

5.         Paragraph 4(a) of the Agreement is amended to read as follows:

           (a)      Disability. If, as a result of the incapacity of the
                    ----------
                    Executive due to physical or mental illness, the Executive
                    is unable to perform substantially and continuously the
                    duties assigned to him hereunder, with or without reasonable
                    accommodation, for a period of five (5) consecutive months
                    or for a non-consecutive period of nine (9) months during
                    the Term of Employment, the Company may terminate his
                    employment for "Disability" upon thirty (30) days prior
                    written notice to the Executive.

6.         Paragraphs 6 (c) and (d) of the Agreement are amended to read as
           follows:

           (c)      Non-competition. The Executive agrees that, during the term
                    ---------------
                    of Employment and for a period of two (2) years following
                    the date of termination of the Executive's employment with
                    the Company for any reason, the Executive will not, directly
                    or indirectly, own, manage, operate, control or participate
                    in the ownership, management or control of, or be connected
                    as an officer, employee, partner, director, or otherwise
                    with, or have any financial interest in, or aid or assist
                    anyone else in the conduct of, any entity or business that
                    competes with any business conducted by the Company or any
                    of its subsidiaries or affiliates, in any area where such
                    business is being conducted on the date of the Executive's
                    employment is terminated hereunder and as to which the
                    Executive has material responsibilities.

           (d)      Further Covenant. Until the date which is two (2) years
                    ----------------
                    after the date of the termination of the Executive's
                    employment hereunder for any reason, the Executive will not,
                    directly or indirectly, take any of the following actions,
                    and, to the extent the Executive owns, manages, operates,
                    controls, is employed by or participates in the ownership,
                    management,
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                                                                     Page 3 of 3

                    operation or control of, or is connected in any manner with,
                    any business of the type and character engaged in and
                    competitive with that conducted by the Company or way of the
                    Affiliates during the period of the Executive's employment,
                    the Executive will use his best efforts to ensure that such
                    business does not take any of the following actions:

                    (i)      persuade or attempt to persuade any client of the
                             Company to cease doing business with the Company or
                             any Affiliate, or to reduce the amount of business
                             it does with the Company or any Affiliate;

                    (ii)     solicit for himself or any entity the business of a
                             client of the Company or any Affiliate, or solicit
                             any business which was a client of the Company or
                             any Affiliate within six months prior to the
                             termination of the Executive's employment;

                    (iii)    persuade or attempt to persuade any employee of the
                             company or any Affiliate or any individual who was
                             its employee of the Company or any Affiliate during
                             the two (2) years prior to the Executive's
                             termination of employment, to leave the employ of
                             the Company or any of its subsidiaries or
                             affiliates.

         7.      Except as amended in the above paragraphs, all of the terms of
                 the December 14, 1998 agreement shall remain in effect.

         IN WITNESS WHEREOF, the Company and the Executive have executed this
Amendment No. One as of the date first written above.

CRAIG S. CINALLI                          BETTER MATERIALS CORPORATION

________________________________          By:   _____________________________
                                                Name:

                                                Title:

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