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                                                                   EXHIBIT 10.17

Assignment Agreement made May 26, 2000 between UCAR Graph-Tech Inc., a Delaware
corporation ("ASSIGNOR"), and UCAR Carbon Company Inc., a Delaware corporation
("ASSIGNEE").


RECITALS:

WHEREAS a Memorandum of Understanding was made on April 12, 2000 between the
ASSIGNOR and Mazarin Mining Corporation Inc. ("MAZARIN") with respect to a
graphite deposit located at Lac Knife in the Province of Quebec, Canada and to
an acquisition by the ASSIGNOR or a company to be owned by or affiliated to the
ASSIGNOR of an Equity Investment (as this term is defined at section 1
hereinafter) in the share capital of MAZARIN (the "MOU");

WHEREAS the ASSIGNEE is an affiliate of the ASSIGNOR as the term affiliate is
defined in the MOU;

WHEREAS the ASSIGNOR and the ASSIGNEE wish to enter into an agreement whereby
the rights, interests and benefits under the MOU with respect to the transfer,
assignment and conveyance of the rights, benefits and interests of the ASSIGNOR
provided for in the MOU but only as they concern the Equity Investment as above
described are assigned, transferred and conveyed to the ASSIGNEE;

WHEREAS the ASSIGNOR and the ASSIGNEE wish to hereby consign in writing the
terms and conditions of their agreements as to said assignment, transfer and
conveyance;


NOW THIS AGREEMENT WITNESSES AS FOLLOWS:

1.       ASSIGNMENT. For good and valid consideration, of which the ASSIGNOR
         acknowledges receipt and for which release and discharge is hereby
         given, the ASSIGNOR assigns, transfers and conveys its rights, benefits
         and interests with respect to the acquisition of an equity investment
         in the share capital of MAZARIN as provided for in the MOU, in
         particular at section 6 of its recitals, at its section 10 and at its
         Appendix "B" (the "Equity Investment") to the ASSIGNEE, who accepts
         such assignment, transfer and conveyance.

2.       ASSUMPTION. The ASSIGNEE hereby agrees to be bound by the provisions of
         the MOU as they concern the Equity Investment and assume the ASSIGNOR'S
         obligations, undertakings, representations and warranties as they
         relate specifically to said Equity Investment and as if the ASSIGNEE,
         in this regard, had signed the MOU, in the place of the ASSIGNOR.

3.       NOTICES. Any notice or other communication to be given hereunder may be
         effectively given to a party by delivering the same at the addresses
         hereinafter set forth or by sending the same by prepaid registered
         mail, prepaid courier or telecopy to such party at such addresses and
         numbers. Any notice so mailed shall be deemed to have been received on
         the third (3rd) business day following the mailing thereof and if given
         by delivery or telecopy the same shall be deemed to have been received
         upon delivery or upon
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         transmission. The mailing and telecopy address of the parties for the
         purposes hereof shall be:

         3.1      If to the ASSIGNOR:

                  UCAR GRAPH-TECH INC.
                  11709, Madison Avenue
                  Lakewood, Ohio 44107
                  USA

                  Attention:
                  Facsimile: (216) 529-3888

         3.2      If to the ASSIGNEE:

                  UCAR CARBON COMPANY INC.
                  3102 West End Avenue, Suite 1100
                  Nashville, Tennessee 37203
                  USA

                  Attention:
                  Facsimile: (615) 760-7785

         Any party may from time to time notify the other in accordance with the
         provisions hereof of any change of address which thereafter, until
         changed by like notice, shall be the address of such party for the
         purposes of this agreement. In the event of actual or threatened postal
         interruption, notice shall be made by delivery or telecopy. Receipt of
         a courtesy copy of any notice or other communication shall not be a
         condition to the effectiveness thereof.

4.       INVALID OR UNENFORCEABLE PROVISIONS. If any provision of this agreement
         is judicially determined to be invalid or unenforceable, the remainder
         of this agreement shall not be affected thereby and shall be applied
         and construed as if such invalid or unenforceable provision had been
         omitted.

5.       FURTHER ASSURANCES. Each party shall do such acts and shall execute
         such further documents, conveyances, deeds, assignments, transfers and
         the like and will cause the doing of such acts and will cause the
         execution of such further documents as are within its powers as any
         other party may in writing at any time and from time to time reasonably
         request to be done and/or executed, in order to give full effect to the
         provisions of the present agreement.

6.       ENTIRE AGREEMENT. This agreement, with respect to its specific subject
         matter, together with any agreements and other documents to be
         delivered pursuant hereto constitutes the only and entire agreement
         between the parties pertaining to the subject matter hereof and
         supersedes all prior agreements, negotiations, discussions and
         understandings, written or oral between the parties. There are no
         representations, warranties, conditions, other

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         agreements or acknowledgments, whether direct or collateral, express
         or implied, that form part or affect this agreement.

7.       ENGLISH LANGUAGE. The parties have expressly required that this
         agreement and all documents and notices relating hereto be drafted in
         English. Les parties aux presentes ont expressement exige que la
         presente convention et tous les documents et avis qui y sont afferents
         seront rediges en anglais.

8.       GOVERNING LAW. This agreement evidences a binding agreement between the
         parties and shall be governed by and construed in accordance with the
         laws of Ontario and the federal laws applicable therein.

9.       RECITALS. The recitals form an integral part of the present agreement.

IN WITNESS WHEREOF the parties hereto have executed this agreement in as of the
date first above written,

                                             THE ASSIGNOR

                                             UCAR GRAPH-TECH INC.


                                             Per:  /s/ John J. Wetula
                                                   ------------------------
                                                   (Authorized signature)

                                                   President
                                                   ------------------------
                                                   (Position)


                                             THE ASSIGNEE

                                             UCAR CARBON COMPANY INC.


                                             Per:  /s/ Craig S. Shular
                                                   -------------------------
                                                   (Authorized signature)


                                                   EVP-CFO
                                                   -------------------------
                                                   (Position)



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                                     CONSENT


Mazarin Mining Corporation Inc. ("MAZARIN"), a Quebec corporation, hereby
declares that it has examined the present agreement, is satisfied of its content
and, to the extent this may be required, consents to the assignment, transfer
and conveyance described therein in accordance with its terms and conditions.

IN WITNESS WHEREOF, MAZARIN has executed the present consent in Quebec City, as
of the date first above written.


                                                MAZARIN MINING CORPORATION INC.




                                                Per:/s/ J. Bonneau
                                                    -------------------------
                                                    (Authorized signature)


                                                    President - C.E.O.
                                                    -------------------------
                                                    (Position)


                                                Per:/s/ Robert Dutil
                                                    -------------------------
                                                    (Authorized signature)


                                                    Chairman
                                                    -------------------------
                                                    (Position)


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