EXHIBIT 2.3

                                AMENDMENT NO. 1

                                      TO

                   LLC INTEREST SALE AND PURCHASE AGREEMENT



     AMENDMENT NO. 1 TO LLC INTEREST SALE AND PURCHASE AGREEMENT ("Amendment No.
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1") dated as of September 30, 1998 among OWENS CORNING, a Delaware corporation
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("Seller"), ADVANCED GLASSFIBER YARNS LLC (formerly, Lincoln Yarns, LLC), a
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Delaware limited liability company (the "Company"), and AGY HOLDINGS, INC., a
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Delaware corporation ("Buyer").
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                              W I T N E S S E T H
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     WHEREAS, Seller, the Company and Glass Holdings, Inc. entered into a LLC
Interest Sale and Purchase Agreement dated as of July 31, 1998 (the "Purchase
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Agreement"), which Purchase Agreement was assigned by Glass Holdings, Inc. to
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Buyer by an Assignment and Assumption Agreement dated September 30, 1998; and

     WHEREAS, Seller, the Company and Buyer desire to make certain amendments to
the Purchase Agreement, all as set forth below;

     NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

1.   Defined Terms.  Except as otherwise expressly provided herein, capitalized
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terms used herein which are defined in the Purchase Agreement, as amended
hereby, shall have the meanings specified for such terms in the Purchase
Agreement, as so amended.

2.   Amendments to Purchase Agreement.
     -------------------------------- 

     (a)  Section 1.2 of the Purchase Agreement shall be amended to read as
follows:

          "The aggregate purchase price for the Buyer Interest shall be three
          hundred thirty one million five hundred thousand Dollars
          ($331,500,000) in the aggregate, subject to adjustment as provided in
          Section 1.4 (the "Purchase Price")."
                            --------------    

     (b)  Section 1.4 of the Purchase Agreement is hereby amended to read as
follows:

          "1.4  Cash Payment for Change in Net Asset Value.
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     (a)  Calculation of the Cash Payment. The Company shall make a cash payment
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     (the "NAV Payment") in the amount by which the Net Asset Value of the
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     Company as of the Closing Date (the "Closing NAV"), as finally determined
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     pursuant to Section 1.4(d) below, is greater or less than thirty one
     million seven hundred thirty eight thousand dollars ($31,738,000)(the "Base
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     NAV").  The calculation of the Base NAV is set forth on Schedule 1.4(a).
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     If the Closing NAV is greater than the Base NAV, then the Company shall
     make the NAV Payment to Jefferson Holdings, Inc. ("Jefferson").  If the
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     Closing NAV is less than the Base NAV, then the Company shall make the NAV
     Payment to Buyer.  Such NAV Payment shall be paid as set forth in Sections
     1.4(b) and (e) below.

     (b)  Estimated Adjustment. On the Closing Date, Seller shall deliver to
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     Buyer a statement (the "Estimated Closing Statement") prepared in
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     accordance with GAAP setting forth a calculation of Seller's good faith
     estimate of the Closing NAV (the "Estimated Closing NAV"). If the
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     Estimated Closing NAV as set forth on the Estimated Closing Statement is
     in excess of the Base NAV, the Company shall make the NAV Payment to
     Jefferson at Closing. If the Estimated Closing NAV as set forth on the
     Estimated Closing Statement is less than the Base NAV, then the Company
     shall make the NAV Payment to Buyer at Closing.

     (c)  Closing NAV.  Within ninety (90) days after the Closing, Seller will
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     prepare and deliver to Buyer a balance sheet of the Company as of the
     Closing Date prepared in accordance with GAAP together with a statement
     setting forth a calculation of the Closing NAV (the "Closing Statement").
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     At the option of the Buyer, exercisable in writing on or before the Closing
     Date, the Closing Statement shall be audited by PricewaterhouseCoopers LLP.
     The cost of such audit shall be borne by the Company.  Buyer shall
     cooperate fully and shall cause the Company to provide Seller with all
     assistance and access to books and records necessary for Seller to prepare
     the Closing Statement.  In connection therewith, Buyer and Seller will
     jointly conduct a physical inventory of the Inventory as of the Closing
     Date in accordance with the procedures to be mutually agreed by Buyer and
     Seller acting reasonably and in good faith and, at Buyer's option, such
     physical inventory will be observed by Buyer's auditors,
     PricewaterhouseCoopers LLP, and, at Seller's option, such physical
     inventory will be observed by Seller's auditors, Arthur Andersen LLP.

     (d)  Closing Calculation.
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          (i) Buyer shall be entitled to full access to the relevant records and
     working papers prepared by or for Seller, and to Seller's employees
     involved in such preparation, to aid in its review of the calculation of
     the Closing NAV set forth on the Closing Statement. If Buyer believes that
     the Closing NAV calculation (hereinafter the "Closing Calculation") has not
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     been properly calculated in accordance with the calculation methodologies
     set forth in this Section 1.4, it shall,

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     within thirty (30) days after receipt of the Closing Calculation, give
     written notice (the "Buyer's Objection") to Seller, setting forth the basis
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     of the Buyer's Objection in reasonable detail and, to the extent
     practicable, the adjustments to the Closing Calculation which Buyer
     believes should be made. Failure to so notify Seller within such thirty
     (30) day period shall constitute acceptance and approval of the Closing
     Calculation. There shall be no adjustment to the Closing Calculation unless
     the cumulative amount of Buyer's Objection equals or exceeds one million
     dollars ($1,000,000.00) and provided that any individual item of adjustment
     contained in Buyer's Objection which is less than fifty thousand dollars
     ($50,000.00) shall be excluded in its entirety. If Seller agrees that any
     change proposed by Buyer is appropriate, the change shall be made to the
     Closing Calculation, whereupon Buyer shall be deemed to have accepted and
     approved the Closing Calculation with respect to such change and any other
     non-disputed item of the Closing Calculation. If the proposed change is
     disputed by Seller, then Seller and Buyer shall negotiate in good faith to
     resolve such dispute as expeditiously as possible. If, after a period of
     thirty (30) days following the date on which Buyer gives Seller notice of
     any such proposed change, any such proposed change still remains disputed,
     then:

          (ii)  KPMG Peat Marwick LLP (the "Neutral Accounting Firm") shall be
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     engaged to resolve any remaining disputes. The Neutral Accounting Firm
     shall act as an arbitrator to determine, based solely on presentations
     submitted by Seller and Buyer, and not by independent review, only those
     issues still in dispute. Each of Buyer and Seller shall have made its
     complete submission to the Neutral Accounting Firm within ten (10) days
     following the expiration of the thirty (30) day negotiation period
     described in Section 1.4(d)(i). The failure by either party to make a
     complete submission prior to the expiration of such ten (10) day period
     shall be deemed a waiver of such party's right to make a submission or a
     further submission to the Neutral Accounting Firm. The Neutral Accounting
     Firm's determination, based upon the calculation methodologies set forth in
     this Section 1.4, shall be made within thirty (30) days following the date
     on which the dispute is submitted, shall be set forth in a written
     statement delivered to Seller and Buyer, and shall be final, binding and
     conclusive. The fees and any expenses of the Neutral Accounting Firm shall
     be shared equally by Seller and Buyer. In the event a party does not comply
     with the procedure and time requirements contained herein, the Neutral
     Accounting Firm shall render a decision based solely on the evidence it has
     which was timely filed by either of the parties.

     (e)  Payment of Cash NAV Payment.  If the Closing NAV shown on  the Closing
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     Statement exceeds the Estimated Closing NAV, then the Company shall make
     the NAV Payment to Jefferson, and if the Closing NAV shown on the Closing
     Statement is less than the Estimated Closing NAV, then the Company shall
     make the NAV Payment to Buyer. Payment of any NAV Payment pursuant to this
     Section 1.4(e) shall be made by wire transfer to an account designated by
     Jefferson or Buyer, as the 

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          case may be, in United States Dollars, in immediately available
          federal funds within three (3) business days after the Closing
          Calculation has been finally determined together with interest from
          the Closing Date to the date of payment at the "base rate" of
          Citibank, N.A. or any successor thereto in New York, New York in
          effect on the Closing Date, based on a 360-day year."

     (c)  Schedule 1.4(a) of the Purchase Agreement is hereby amended to read as
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set forth on Exhibit A hereto.

     (d)  Section 2.20 of the Purchase Agreement is hereby amended to read as
     follows:

          "Section 2.20  Disclaimer of Warranty.
                         ---------------------- 

          SELLER MAKES NO WARRANTY WITH RESPECT TO THE VALUE, CONDITION OR,
          SUBJECT TO SECTION 2.19, USE OF THE ASSETS OWNED OR USED BY THE
          COMPANY, WHETHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION,
          ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
          PURPOSE."

     (e)  Section 4.20 of the Purchase Agreement is hereby amended to insert the
words "to execute and deliver" after the words "Jefferson Holdings, Inc." in the
first line.

     (f)  Section 4.29 of the Purchase Agreement is hereby amended to read as
     follows:

          "4.29  Purchase of Assets from Seller's Subsidiaries.  The parties
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          acknowledge that, pursuant to agreements dated September 29, 1998, the
          Company has purchased certain assets from, and has assumed certain
          liabilities of, Owens-Corning (Japan) Ltd., OCC and NVOC (the
          "Subsidiary Asset Purchase Agreements").  The parties agree that to
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          the extent that there is any adjustment to the Purchase Price pursuant
          to Section 2(b) of each of the Subsidiary Asset Purchase Agreements,
          any payment required to be paid by the Company shall be paid by the
          Seller, and any amount required to be paid to the Company shall be
          paid to the Seller."

     (g)  Section 4.34(i) of the Purchase Agreement is hereby amended to read as
     follows:

          "(i)  Stock Options.  Each outstanding option to purchase Seller
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          common stock held by Transferred Employees shall vest immediately upon
          the Closing and expire on the earlier of (a) December 31, 1999 or (b)
          the date on which the option expires by the terms of the applicable
          option contract.  The Company agrees to indemnify Seller for any costs
          or other damages incurred by Seller in connection with the extension
          of any option beyond six months following the Closing."

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     (h)  Section 4.38 of the Purchase Agreement is hereby amended to read as
     follows:

          "4.38  Post-Closing Distributions by the Company.
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                 Immediately upon the Closing, the parties shall cause the
          Company to, and the Company shall, make a cash distribution in the
          aggregate amount of three hundred ninety million Dollars
          ($390,000,000) to its members, pro rata in accordance with their then
          respective ownership interests in the Company, and Buyer shall have
          caused the Company to obtain any and all financing necessary to fund
          such cash distribution (the "Company Financing") in accordance with
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          the terms and conditions set forth in the Commitments. In addition,
          the parties shall cause the Company to, and the Company shall, make
          the NAV Payment in accordance with and in the form and manner
          described in Section 1.4 of this Amendment No. 1."

     (i)  Schedule 7.1 of the Purchase Agreement is hereby amended to read as
          ------------
set forth on Exhibit B hereto.

     (j)  Section 10.10(a) of the Purchase Agreement is hereby amended to revise
the definitions of "Material Adverse Effect" and "Net Asset Value" to read as
follows:

          " "Material Adverse Effect" has the meaning ascribed to it in Section
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          2.2.

          "Net Asset Value" means the sum of Total Current Assets less Current
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          Liabilities as reflected in the Pro Forma Statement of Net Assets to
          be sold as of 12/31/97 but excluding Trade Payables (which shall be
          paid in full immediately prior to the Closing Date), with such amounts
          determined in accordance with GAAP using the same assumptions
          reflected in the 12/31/97 Historical Financial Statements and
          methodology in calculating the Base NAV as set forth in Schedule
          1.4(a)."

     (k)  Section 10.10(a) of the Purchase Agreement is hereby amended to add
the following new definitions in appropriate alphabetical order:

          " "Jefferson" has the meaning ascribed to it in Section 1.4(a).
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          "NAV Distribution" has the meaning ascribed to it in Section 1.4(a).
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          "Subsidiary Asset Purchase Agreement" has the meaning ascribed to it
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          in Section 4.29."

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     (l) Section 10.10(a) of the Purchase Agreement is hereby amended to delete
the following definitions: "NVOC Assets," "NVOC Asset Purchase Agreement," "OCC
Assets" and "OCC Asset Purchase Agreement."

     (m) The Purchase Agreement is hereby amended to delete Exhibits V and W
therefrom.

3.   Condition to Effectiveness of Amendment No. 1.
     --------------------------------------------- 

     The amendments contained in this Amendment No. 1 are subject to and
conditioned upon the Closing occurring on or before September 30, 1998.

4.   Representations and Warranties.
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     (a)  Seller represents and warrants to Buyer that:

          (i)  Each of Seller and the Company has the corporate power and
authority to execute and deliver this Amendment No. 1.

          (ii) This Amendment No. 1 is the legal, valid and binding obligation
of Seller and the Company enforceable against each of them in accordance with
the terms hereof.

     (b)  Buyer represents and warrants to Seller that:

          (i)  Buyer has the corporate power and authority to execute and
deliver this Amendment No. 1.

          (ii) This Amendment No. 1 is the legal, valid and binding obligation
of Buyer enforceable against it in accordance with the terms hereof.

5.   Miscellaneous.
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     (a)  Amendment to Purchase Agreement. This Amendment No. 1 shall be
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construed, administered and applied in accordance with all of the terms and
provisions of the Purchase Agreement.

     (b)  Successors and Assigns. This Amendment No. 1 shall inure to the
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benefit of and be binding on the parties hereto and their respective successors
and permitted assigns.

     (c)  Effect of Amendment No. 1.  The amendments hereunder shall be limited
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precisely as written and shall not constitute a waiver or modification of any
other covenants, terms or provisions of the Purchase Agreement, which shall
remain in full force and effect.

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     (d)  Amendment; Waiver. This Amendment No. 1 may be amended, supplemented
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or otherwise modified only by a written instrument executed by the parties
hereto. No waiver by either party of any of the provisions hereof shall be
effective unless explicitly set forth in writing and executed by the party so
waiving.

     (e)  Governing Law. This Amendment No. 1 shall be governed by, and
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construed in accordance with, the laws of the state of New York applicable to a
contract executed and performed in such State without giving effect to the
conflicts of laws principles thereof, except that matters herein strictly within
the purview of the matters covered by the Limited Liability Company Act of the
State of Delaware shall be governed by such Limited Liability Company Act.

     (f)  Counterparts. This Amendment No. 1 may be executed by the parties
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hereto in separate cou nterparts, each of which when so executed and delivered
shall be an original, but all such counterparts shall together constitute one
and the same agreement, and all signatures need not appear on any one
counterpart.

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     IN WITNESS WHEREOF, the parties have caused this Amendment No. 1 to be duly
executed as of the date first above written.



                              OWENS CORNING

                              By: /s/ Charles E. Dana
                                  ----------------------
                                  Name:
                                  Title:


                              GLASS HOLDINGS, CORP.


                              By: /s/ Robert Porcher
                                  ----------------------
                                  Name: Robert Porcher
                                  Title: President


                              ADVANCED GLASSFIBER YARNS LLC
                              By: Owens Corning, Member


                              By: /s/ Charles E. Dana
                                  ----------------------
                                  Name:
                                  Title:

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