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                                                              Exhibit 4(j)

    THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE 
SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, ASSIGNED OR 
TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES 
UNDER THE SECURITIES ACT OF 1933, AS AMENDED, UNLESS THE COMPANY HAS RECEIVED 
THE WRITTEN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY TO THE EFFECT THAT 
SUCH SALE, ASSIGNMENT OR TRANSFER DOES NOT INVOLVE A TRANSACTION REQUIRING 
REGISTRATION OF SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED.

Issue Date:   September 22, 1997
Void After:   September 21, 2000                 Right to Purchase 60,000
                                                 Shares of Common Stock 
                                                 Stock (subject to adjustment) 
                                                 of Nuclear Metals, Inc.


                                 NUCLEAR METALS, INC.
                            COMMON STOCK PURCHASE WARRANT


    THIS CERTIFIES that, in consideration of value received, Roger Marino 
(the "Holder"), is entitled, upon the terms and subject to the conditions 
hereinafter set forth, to subscribe for and purchase from Nuclear Metals, 
Inc., a Massachusetts corporation (the "Company"), Sixty Thousand (60,000) 
fully paid and nonassessable shares of the Company's Common Stock, $0.10 par 
value per share (the "Common Stock").  The number and exercise price of the 
securities that may be purchased upon the exercise of this Common Stock 
Purchase Warrant (the "Warrant") are subject to adjustment as provided herein.

    1.   Exercise Period and Price - The purchase rights represented by this 
Warrant are exercisable by the Holder, in whole or in part, at any time from 
time to time during the Exercise Period at the Exercise Price.  The Exercise 
Price shall initially be $17.875 per share of Common Stock subject to 
adjustment as hereinafter provided.  

    The Exercise Period shall commence at 9:00 a.m. Boston, Massachusetts 
time on the date first set forth above and shall end at 5:00 p.m. Boston, 
Massachusetts time on the third anniversary of such date.  

    2.   Exercise of Warrant - During the Exercise Period and provided this 
Warrant has not been terminated, this Warrant shall be exercised, in whole or 
in part and from time to time, by the surrender of this Warrant and the 
Notice of Exercise annexed hereto duly executed at the principal office of 
the Company, in Boston, Massachusetts (or such other office or agency of the 
Company as it may designate) and upon payment of the Exercise Price of the 
shares thereby purchased (payment to be by check or bank draft payable to the 
order of the Company).  If the amount of the payment received by the Company 
is less than

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the Exercise Price, the Holder will be notified of the deficiency and shall 
make payment in that amount within three days.  In the event the payment 
exceeds the Exercise Price, the Company will refund the excess to the holder 
within three days of receipt.  Upon exercise, the Holder shall be entitled to 
receive, within a reasonable time after payment in full, one or more 
certificates, issued in the Holder's name or in such name or names as the 
Holder may direct, subject to the limitations on transfer contained herein, 
for the number of shares of Common Stock so purchased.  The shares so 
purchased shall be deemed to be issued as of the close of business on the 
date on which this Warrant shall have been exercised.

    The Company covenants that all shares of Common Stock that are issued 
upon the exercise of rights represented by this Warrant will be fully paid, 
nonassessable, and free from all taxes, liens and charges in respect of the 
issue thereof (other than taxes in respect of any transfer occurring 
contemporaneously with such issue).

    3.   No Fractional Shares or Scrip - No fractional shares or scrip 
representing fractional shares shall be issued upon the exercise of this 
Warrant.  In lieu thereof, a cash payment shall be made equal to such 
fraction multiplied by the Exercise Price per share as then in effect.

    4.   Charges, Taxes and Expenses - Issuance of certificates for shares of 
Common Stock upon the exercise of this Warrant shall be made without charge 
to the Holder for any issue or transfer tax or other incidental expense in 
respect of the issuance of such certificate, all of which taxes and expenses 
shall be paid by the Company.

    5.   No Rights as Shareholder - This Warrant does not entitle the Holder 
to any voting rights or other rights as a shareholder of the Company prior to 
exercise and payment of the Exercise Price in accordance with Section 2 
hereof.  

    6.   Sale or Transfer of the Warrant; Legend - This Warrant shall not be 
sold or transferred unless either (i) it first shall have registered under 
the 1933 Act and any applicable state securities laws, or (ii) the Company 
first shall have been furnished with an opinion of legal counsel reasonably 
satisfactory to the Company to the effect that such sale or transfer is 
exempt from the registration requirements of the 1933 Act and such state 
laws.  Each certificate representing any Warrant that has not been registered 
and that has not been sold pursuant to an exemption that permits removal of 
the legend shall bear a legend substantially in the form of the legend 
affixed to this Warrant.

Upon the request of a holder of a certificate representing any Warrant, the 
Company shall remove the foregoing legend from the certificate or issue to 
such holder a new certificate therefor free of any transfer legend, if, with 
such request, the Company shall have received either (i) an opinion of 
counsel reasonably satisfactory to the Company to the effect that such legend 
may be removed from such certificate or (ii) if the present Paragraph (k) of 
Rule 144 or a substantially similar successor rule remains in force and 
effect, representations from the 

                                         -2-
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holder that such holder is not then, and has not been during the preceding 
three months, an affiliate of the Company and that such holder has 
beneficially owned the security (within the meaning of Rule 144) for three 
years or more.

    Such Warrant may be subject to additional restrictions on transfer 
imposed under applicable state and federal securities law.

    7.   Adjustments

         7.1  Adjustments for Stock Splits, Reverse Stock Splits and Stock 
Dividends     In the event that the outstanding shares of Common Stock shall 
be subdivided (split), combined (reverse split), by reclassification or 
otherwise, or in the event of any dividend payable on the Common Stock in 
shares of Common Stock, the number of shares of Common Stock available for 
purchase in effect immediately prior to such subdivision, combination, or 
dividend shall be proportionately adjusted. 

         7.2  Adjustment for Capital Reorganizations - If at any time there 
shall be a capital reorganization of the Company or a merger or consolidation 
of the Company with or into another corporation, or the sale of the Company's 
properties and assets as, or substantially as, an entirety to any other 
person, then, as part of such reorganization, merger, consolidation, or sale, 
lawful provision shall be made so that the Holder of this Warrant shall 
thereafter be entitled to receive on exercise of this Warrant during the 
period specified in this Warrant and on payment of the Exercise Price then in 
effect, the number of shares of stock or other securities or property of the 
Company, or of the successor corporation resulting from such merger or 
consolidation, to which a holder of the Common Stock deliverable on exercise 
of this Warrant would have been entitled on such capital reorganization, 
merger, consolidation, or sale if this Warrant had been exercised immediately 
before that capital reorganization, merger, consolidation, or sale.  In any 
such case, appropriate adjustment, as determined in good faith by the Board 
of Directors of the Company, shall be made in the application of the 
provisions of this Warrant with respect to the rights and interests of the 
Holder of this Warrant after the reorganization, merger, consolidation, or 
sale to the end that the provisions of this Warrant (including adjustment of 
the number of shares purchasable on exercise of this Warrant) shall be 
applicable after that event, as near as reasonably may be, in relation to any 
shares or other securities or property deliverable after that event on 
exercise of this Warrant.

         7.3  Certificate as to Adjustments - Upon the occurrence of each 
adjustment or readjustment pursuant to this Section 7, the Company at its 
expense shall promptly compute such adjustment or readjustment in accordance 
with the terms hereof and furnish to each Holder a certificate setting forth 
such adjustment or readjustment and showing in detail the facts upon which 
such adjustment or readjustment is based.  The Company shall, upon the 
written request, at any time, of any Holder, furnish or cause to be furnished 
to such Holder, a like certificate setting forth:  (i) such adjustments and 
readjustments; (ii) the Exercise Price at the time in effect; and (iii) the 
number of shares of Common Stock and the 

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amount, if any, of other property that at the time would be received upon the 
exercise of the Warrant.

         7.4  Notices of Record Date - In the event of any taking by the 
Company of a record of the holders of any class of securities for the purpose 
of determining the holders thereof who are entitled to receive any dividend 
(other than a cash dividend that is the same as cash dividends paid in 
previous quarters) or other distribution, the Company shall mail to each 
Holder at least ten days prior to the date specified for the taking of a 
record, a notice specifying the date on which any such record is to be taken 
for the purpose of such dividend or distribution.

    8.   Reservation of Stock, etc., Issuable on Exercise of Warrant - The 
Company will at all times reserve and keep available, solely for issuance and 
delivery upon the exercise of this Warrant, all shares of Common Stock (or 
other securities) from time to time issuable upon the exercise of this 
Warrant and all shares of Common Stock issuable upon conversion of such 
shares of Common Stock.

    9.   Loss, Theft, Destruction or Mutilation of Warrant - Upon receipt by 
the Company of evidence reasonably satisfactory to it of the loss, theft, 
destruction, or mutilation of this Warrant, and in case of loss, theft, or 
destruction, of indemnity or security reasonably satisfactory to it, and upon 
reimbursement to the Company of all reasonable expenses incidental thereto, 
and upon surrender and cancellation of this Warrant, if mutilated, the 
Company will make and deliver a new Warrant of like tenor and dated as of 
such cancellation in lieu of this Warrant.

    10.  Remedies - The Company stipulates that the remedies at law of the 
holder of this Warrant in the event of any default or threatened default by 
the Company in the performance of or compliance with any of the terms of this 
Warrant are not adequate and may be enforced by a decree for the specific 
performance of any agreement contained herein or by an injunction against a 
violation of any of the terms hereof or otherwise.

    11.  Notices, etc. - All notices and other communications from the 
Company to the holder of this Warrant shall be mailed, by first class mail, 
to such address as may have been furnished to the Company in writing by such 
holder, or, until an address is so furnished, to and at the address of the 
last holder of this Warrant who has so furnished an address to the Company.  
All communications from the holder of this Warrant to the Company shall be 
mailed by first class mail to the Company's principal office, or such other 
address as may have been furnished to the holder in writing by the Company.

    12.  Miscellaneous - This Warrant shall be construed and enforced in 
accordance with and governed by the laws of The Commonwealth of 
Massachusetts. The headings in this Warrant are for purposes of reference 
only, and shall not limit or otherwise affect any of the terms hereof.

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    IN WITNESS WHEREOF, the Company has caused this Warrant to be executed in
its corporate name by its duly authorized officer and to be dated as of the
issue date set forth on the first page of this Warrant.

                                  NUCLEAR METALS, INC.

    
                                  By:  /s/ George J. Matthews
                                     -----------------------------------
                                       Chairman
[CORPORATE SEAL]        

Attest:


/s/ Thomas A. Wooters
-----------------------------------
Clerk


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                             NOTICE OF EXERCISE OF Common
                                STOCK PURCHASE WARRANT


TO:  Nuclear Metals, Inc.

    (1)  Pursuant to the terms of the attached Warrant, the undersigned 
hereby elects to purchase ______ shares of Common Stock of Nuclear Metals, 
Inc. (the "Company"), and either (i) tenders herewith payment of the Exercise 
Price of such shares in full or (ii) by indicating "cashless exercise" below, 
directs that payment of the Exercise Price be made by cancellation as of the 
date of exercise of a portion of this Warrant having a net fair market value 
equal to the Exercise Price.

    (2)  Please issue a certificate or certificates representing said shares 
of Common Stock, in the name of the undersigned or in such other name(s) as 
is/are specified immediately below or, if necessary, on an attachment hereto:

              Name                          Address
              ----                          -------








    (3)  In the event of partial exercise, please reissue an appropriate
Warrant exercisable into the remaining shares.




DATE:____________________              HOLDER:_____________________________



Check here if cashless exercise: ______