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                                                 FEDERAL EXPRESS
                                                 December 23, 1997

Investors
c/o Dr. Melvin B. Chrein
21 Copper Beech Lane
Lawrence, NY  11559

    Re:  Sale of Starmet Corporation (formerly Nuclear Metals, Inc.)
         Convertible Debentures

Gentlemen:

    The purpose of this letter is to set forth the following terms and 
conditions which shall apply to the sale of an aggregate of $900,000 Starmet 
Corporation 10% Convertible Subordinated Debentures (the "Debentures") by the 
Company to you.

    The purchase price for the Debentures shall be Nine Hundred Thousand 
($900,000) Dollars.   

    You acknowledge and understand that the Debentures and the underlying 
stock (the "Securities") are being offered and sold without registration 
under the Securities Act of 1933, as amended (the "Act") and in reliance upon 
an exemption from the registration requirements contained in the Act and the 
rules and regulations promulgated thereunder.

    Each of you hereby makes the following representations and warranties to 
the Company: 

    (1)  You are an "accredited investor" within the meaning of Rule
         501(a) under the Act.

    (2)  You have sufficient knowledge and experience in financial and
         business matters which enable you to evaluate the merits and
         risks of making an investment in the Company.  We have provided
         you with any and all public information concerning the Company
         which you deem relevant.  You have had the opportunity to ask and
         have received answers to any questions you have with respect to
         the business and prospects of the Company.  You recognize and
         agree that non-public information provided to you may be used
         only for purposes of evaluating the investment described above,
         and for no other purpose.

    (3)  You are acquiring the Securities with your own funds, for your
         own benefit, for investment, and not with a view to the resale or
         distribution thereof or any 

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Investors
December 23, 1997
Page 2


         interest therein.

    (4)  You agree with the Company that, as the Securities are unregistered
         under the Act, they must be held indefinitely unless they are
         subsequently registered under the Act or an exemption from such
         registration is available.  In addition, you agree not to transfer or
         dispose of any of the Securities, or any interest therein, except in
         accordance with all applicable Federal and state laws.  You agree that
         there may be affixed to any certificate representing the Securities
         and to all certificates issued thereafter representing such Securities
         (until in the opinion of counsel, which opinion must be satisfactory
         to counsel to the Company, it is no longer necessary or required) an
         appropriate legend evidencing the applicable restrictions under the
         Act.

    Please acknowledge the foregoing by signing the acknowledgement below and 
returning it to me.  If you have any questions or comments, feel free to give 
me a call. 

                                       Very truly yours,

                                       Starmet Corporation

                                       By: /s/ James M. Spiezio
                                          ------------------------

Acknowledgement of :

/s/ Melvin B. Chrein                   /s/ Marshall J. Chrein
---------------------------            ---------------------------
Melvin B. Chrein                       Marshall J. Chrein

WIAF Investors Co.

By: /s/ Charles Alpert                 /s/ George J. Matthews
    ----------------------             ---------------------------
                                       George J. Matthews

Joshua M. Feibusch, MD, PC

By: /s/ Joshua M. Feibusch
    ----------------------

TAW:cy
Enclosure
cc: Robert E. Quinn, President