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                                                               Exhibit 10(ll)

                       SECOND ADDITIONAL REVOLVING CREDIT NOTE


$3,000,000                                                 December 29, 1997

    FOR VALUE RECEIVED, the undersigned, STARMET CORPORATION, STARMET POWDERS,
LLC, STARMET AEROCAST, LLC, STARMET COMCAST, LLC, STARMET NMI CORPORATION,
STARMET CMI CORPORATION, STARMET HOLDINGS CORPORATION, NMI FOREIGN SALES
CORPORATION (the "Borrowers"), hereby jointly and severally, promise to pay to
the order of STATE STREET BANK AND TRUST COMPANY, a Massachusetts trust company
("Bank"), in lawful money of the United States of America in immediately
available funds at its office at 225 Franklin Street, Boston, Massachusetts
02110 the principal sum of THREE MILLION DOLLARS ($3,000,000) or such lesser sum
as may from time to time be outstanding under the terms of the Credit Agreement
between the Borrowers and Bank of even date herewith, as amended, modified,
supplemented and/or restated from time to time (the "Credit Agreement").

    The Borrowers promise to pay interest on the unpaid principal balance at
the rates and at the times provided in the Credit Agreement.  This Note may be
prepaid only in accordance with the terms of the Credit Agreement.

    The principal balance of this Note shall be reduced as provided in the
Credit Agreement and the remaining balance shall become due and payable on July
15, 1998 and earlier upon the occurrence of an Event of Default (as defined in
the Credit Agreement).  This Note replaces an Additional Revolving Credit Note
dated December 19, 1997 in the principal amount of $1,500,000.  The Borrowers
agree to pay all reasonable legal fees and other costs of collection of this
Note.

    No delay or omission on the part of the holder in exercising any right
hereunder shall operate as a waiver of such right, nor shall any waiver on one
occasion be deemed to be an amendment or waiver of any such right with respect
to any future occasion.  The Borrowers hereby waive presentment, demand, protest
and notice of every kind and assents to any one or more indulgences, to any
substitution, exchange or release of collateral (if at any time there be
available collateral to the holder of this Note) and to the addition or release
of any other party or persons primarily or secondarily liable.


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    This Note shall be governed and construed under the laws of the
Commonwealth of Massachusetts and shall be deemed to be under seal.

                               STARMET CORPORATION

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: VP Finance


                               STARMET POWDERS, LLC

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer

                              STARMET AEROCAST, LLC

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer

                               STARMET COMCAST, LLC

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer


                               STARMET NMI CORPORATION


WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer


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                               STARMET CMI CORPORATION

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer


                               STARMET HOLDINGS CORPORATION

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer


                               NMI FOREIGN SALES CORPORATION

WITNESS: /s/ Rebecca Perry     By: /s/ James M. Spiezio
         -----------------        ---------------------
                               Name: James M. Spiezio
                               Title: Treasurer