AMENDMENT NO. 1
                   TO CONVERTIBLE DEBENTURE PURCHASE AGREEMENT

         This  Amendment  No.  1 to  Convertible  Debenture  Purchase  Agreement
("Amendment") is entered into as of November 27, 1996, by and between FiberCore,
Inc., a Nevada corporation (the "Borrower") having its chief executive office at
174 Charleston Road, Sturbridge,  MA 01566 and AMP INCORPORATED,  a Pennsylvania
corporation  (the  "Lender"),  having  an  office at 470  Friendship  Road,  M/S
176-034, Harrisburg, Pennsylvania 17111.


                                RECITALS OF FACT.

         A.  Borrower and FiberCore  Incorporated,  a Nevada  corporation  ("Old
FiberCore"), previously entered into that certain Convertible Debenture Purchase
Agreement, dated as of April 17, 1995 (the "Purchase Agreement"), pursuant which
Borrower issued to Lender that certain  Convertible  Debenture dated as of April
17,  1995,  in the  original  principal  amount of  $5,000,000,  secured by that
certain Collateral Assignment,  Patent Mortgage and Security Agreement, dated as
of April 17, 1995, made by Old FiberCore in favor of Lender  (collectively,  the
"Existing Loan Documents").

         B. On July 18, 1995,  Old  FiberCore  merged into  Venturecap,  Inc., a
Nevada  corporation  ("Vencap"),  with Vencap (i.e.  Borrower) as the  surviving
corporation (the "Merger").  Simultaneously with the consummation of the Merger,
Vencap changed its name to "FiberCore, Inc."

         C. Borrower assumed the obligations of Old FiberCore, including without
limitation,  the obligations under the Existing Loan Documents,  by operation of
law in the Merger.

         D. The aggregate  principal amount  outstanding under the Existing Loan
Documents is $5,000,000 (the "Existing Loan") and the aggregate accrued interest
on the  Existing  Loan  as of the  date  hereof  is  $541,883.55  with  interest
currently accruing at a rate of $898.97 per day ("Accrued Interest").

         E.  This  Amendment  sets  forth the  manner in which a portion  of the
indebtedness  owed by  Borrower  to Lender  shall be  converted  into  equity of
Lender.

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

         1. PARTIAL  CONVERSION OF THE EXISTING  LOAN.  Lender agrees to convert
$3,000,000  of the  Existing  Loan and  $540,984.58  of  Accrued  Interest  into
3,058,833 shares of Common Stock of Borrower (the "Shares").

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         2. ISSUANCE OF STOCK  CERTIFICATES.  Upon execution of this  Agreement,
Borrower shall issue to Lender (i) a stock  certificate  representing the Shares
and (ii) a new  convertible  debenture in the form of Exhibit A hereto (the "New
Debenture").

         3. REAFFIRMATION OF CONVERTIBLE DEBENTURE PURCHASE AGREEMENT.  Borrower
hereby affirms that there will remain  outstanding,  after partial conversion of
the Existing  Loan  pursuant to Section 1 above,  $2,000,000  of  principal  and
$898.97 of accrued  interest  as of the date  hereof  (with  interest  currently
accruing at the rate of $898.97 per day), which  indebtedness shall be evidenced
by the New  Debenture  and shall be subject to the terms and  conditions  of the
Existing Loan Documents, as amended hereby.

         4. BORROWER'S  REPRESENTATIONS  AND WARRANTIES.  In order to induce the
Lender to enter into this  Amendment  in the manner  provided  herein,  Borrower
represents  and warrants to the Lender that the following  statements  are true,
and correct and complete:

                  a. Authorization of Agreements.  The execution and delivery of
this Amendment and the performance of the Purchase Agreement,  as amended,  have
been duly authorized by all necessary corporate action on the part of Borrower.

                  b.  Incorporation  of  Representations   and  Warranties  From
Purchase Agreement. The representations and warranties contained in Section 3 of
the Purchase Agreement are and will be true and correct in all material respects
on and as of the date hereof to the same extent as though made on and as of that
date,  except to the extent such  representations  and  warranties  specifically
relate to an  earlier  date,  in which  case they were true and  correct  in all
material respects on and as of such earlier date.

                  c. Absence of Default. No event has occurred and is continuing
or will result from the  consummation of the  transactions  contemplated by this
Amendment that would constitute a default under the Purchase Agreement.

         5.  REAFFIRMATION  OF  SECURITY   INTEREST.   That  certain  Collateral
Assignment,  Patent Mortgage and Security Agreement,  made as of April 17, 1995,
by Old FiberCore in favor of Lender (the "Security  Agreement")  shall remain in
full force and effect and is hereby ratified and confirmed by Borrower.  Exhibit
B  hereto  contains  a  true  and  complete  list  of  all  patents  and  patent
applications  of Borrower as of the date  hereof,  domestic  and  foreign.  With
limitation  of the terms and  conditions  of the  Security  Agreement,  Borrower
hereby  agrees from time to time to file any and all  necessary or desirable (i)
Uniform Commercial Code filings and

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(ii) filings or recordations  with the United States Patent and Trademark Office
or any other government  agency,  in order to perfect or maintain the perfection
and first priority of Lender's  security interest in the "Collateral" as defined
in the Security Agreement.

         6. MISCELLANEOUS.

                  a.   Reference To And Effect On The Purchase Agreement.

                           i. On and after the date  hereof,  each  reference in
the Purchase Agreement to "this Agreement",  "hereunder",  "hereof", "herein" or
words of like import in the Existing  Loan  Documents  referring to the Purchase
Agreement,  shall mean and be a reference to the Purchase Agreement,  as amended
by this Amendment.

                           ii. Except as specifically amended by this Amendment,
the Purchase  Agreement and the other Existing Loan  Agreements  shall remain in
full force and effect and are hereby ratified and confirmed.

                           iii. The execution,  delivery and performance of this
Amendment shall not, except as expressly provided herein, constitute a waiver of
any  provision  of, or operate as a waiver of any right,  power or remedy of the
Lender  under  the  Purchase  Agreement  or  any  of  the  other  Existing  Loan
Agreements.

                  b. Headings. Section and subsection headings in this Amendment
are included herein for convenience of reference only and shall not constitute a
part of this Amendment for any other purpose or be given any substantive effect.

                  c.  Applicable  Law. The  Amendment  shall be governed by, and
shall be construed  and enforced in  accordance  with,  the internal laws of the
commonwealth of Massachusetts, without regard to conflicts of laws principles.

                  d. Counterparts.  This Amendment may be executed in any number
of counterparts and by different parties hereto in separate  counterparts,  each
of which when so executed and  delivered  shall be deemed an  original,  but all
such  counterparts  together shall  constitute but one and the same  instrument;
signature pages may be detached from multiple separate counterparts and attached
to a single  counterpart so that all signature pages are physically  attached to
the same document.



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         IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Amendment as of the date set forth above.


Borrower:                                          FIBERCORE, INC.


                                                   By: /s/ Mohd Aslami
                                                       -------------------------
                                                   Name:   Mohd Aslami
                                                   Title:  Chairman and CEO


Lender:                                            AMP INCORPORATED


                                                   By: /s/ James E. Marley
                                                       -------------------------
                                                   Name:   James E. Marley
                                                   Title:  Chairman of the Board

Exhibit A - Convertible Debenture
Exhibit B - List of Patents and Patent Applications



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