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                                                                   EXHIBIT 10.12

                           NORD RESOURCES CORPORATION
                         P.O. BOX 384, OREGON, AZ 85809
                     TEL: (520) 586-2241 FAX: (520) 586-7020

February 20, 2004

Mr. Jeff Carr
Cognis Corporation
5051 East Creek Drive
Cincinatti, OH  46232

BY FAX: (513) 482-5502

Dear Mr. Carr:

I am sending this letter to confirm the acceptance by Cognis Corporation
("Cognis") of the issuance of 28,508 common shares of Nord Resources Corporation
("Nord") as full and final satisfaction of Nord's current debt to Cognis. One
share of Nord's common stock will be issued for each one dollar of debt. The
share certificate will be issued to "Cognis Corporation").

Please indicate the acceptance of this offer by signing below. You may return
the signed letter to me by fax at (520) 219-1877.

All of us at Nord wish to thank both you and Cognis for your acceptance of our
offer. This is an important step in our continuing efforts to reorganize Nord
and we look forward to a "normal" business relationship with Cognis in the
future.

Yours sincerely,


/s/ Erland A. Anderson
-------------------------------------
Erland A. Anderson
President & COO

Accepted:

COGNIS CORPORATION


By: /s/ Michael W. Emery
    ---------------------------------
Name: Michael W. Emery
Title: Director, Accounting Operations

Date: May 24, 2004

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                           NORD RESOURCES CORPORATION

                            DEBT CONVERSION AGREEMENT

THIS DEBT CONVERSION AGREEMENT (the "Agreement") is entered into and made
effective as of the 24th day of May, 2004 (the "Effective Date"), by and BETWEEN
COGNIS CORPORATION, a corporation organized and existing under the laws of the
State of Delaware (the "Investor"), and NORD RESOURCES CORPORATION, a
corporation organized and existing under the laws of the State of Delaware (the
"Company").

                                    RECITALS

WHEREAS, the Company has incurred indebtedness to the Investor in the stated
aggregate amount of Twenty Eight Thousand Five Hundred and Six Dollars
($28,506.00) (the "Debt"); and

WHEREAS, the Company has requested, and the Investor has agreed, to accept
shares of common stock from the Company in settlement and full satisfaction of
the Debt, subject to the terms and conditions set forth in this Agreement.

                                    AGREEMENT

NOW, THEREFORE, in consideration of the foregoing premises, and the mutual
promises and covenants contained in this Agreement, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties, intending to be legally bound, hereby agree as
follows:

1. Company Obligations. Promptly upon the execution of this Agreement, the
Company shall issue to the Investor a stock certificate evidencing the
Investor's ownership of twenty eight thousand five hundred and six (28,506)
shares of its capital common stock (the "Repayment Shares"), at an effective
purchase price of One Dollar ($1.00) per Repayment Share. The parties have
further agreed that, in the event any shares of common stock are sold by the
Company to an investor in any similar debt conversion transaction for less than
the price of One Dollar ($1.00) per share within twelve (12) months from the
Effective Date, then the price of the Repayment Shares shall be adjusted to
reflect the lower purchase price through the issuance of additional Repayment
Shares to the Investor.

2. Investor Obligation. In consideration and payment in full for' the issuance
and delivery of the Repayment Shares to the Investor in accordance with the
provisions of Section 1 above, the Investor hereby agrees to release and
discharge the Company and its respective successors and assigns from any and all
further liability in respect of the Debt, except for the Company's performance
as expressly required under this Agreement.

3. Legends on Stock Certificates. Each certificate representing Repayment Shares
shall contain the following legends on the reverse of such certificate:

     THIS SECURITY HAS NOT BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE
     COMMISSION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR ANY
     STATE SECURITIES DEPARTMENT, IN RELIANCE UPON

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                                       -2-


     THE EXEMPTION FROM REGISTRATION PROVIDED IN SECTION 4(2) OF THE ACT AND
     REGULATION D THEREUNDER. AS SUCH, THE PURCHASE OF THIS SECURITY WAS
     NECESSARILY WITH THE INTENT OF INVESTMENT AND NOT WITH A VIEW FOR
     DISTRIBUTION. THEREFORE, ANY SUBSEQUENT TRANSFER OF THIS SECURITY OR ANY
     INTEREST THEREIN WILL BE UNLAWFUL UNLESS IT IS REGISTERED UNDER THE ACT OR
     UNLESS AN EXEMPTION FROM REGISTRATION IS AVAILABLE. FURTHERMORE, IT IS
     UNLAWFUL TO CONSUMMATE A SALE OR TRANSFER OF THIS SECURITY, OR ANY INTEREST
     THEREIN, WITHOUT THE OPINION OF COUNSEL FOR THE COMPANY THAT THE PROPOSED
     TRANSFER OR SALE DOES NOT AFFECT THE EXEMPTIONS RELIED UPON BY THE COMPANY
     IN ORIGINALLY DISTRIBUTING THIS SECURITY.

     THIS SECURITY HAS NOT BEEN REGISTERED WITH THE OHIO SECURITIES DIVISION
     UNDER THE OHIO SECURITIES ACT, OR ANY OTHER LAW, AND MAY NOT BE RESOLD TO
     ANY PERSON UNLESS AND UNTIL SUCH REGISTRA NON HAS OCCURRED OR PURSUANT TO
     AN EXEMPTION FROM REGISTRATION PERMITTED BY THE APPLICABLE SECURITIES LAWS
     AND REGULATIONS OF THE STATE OF OHIO.

4. Investor Representations. The Investor hereby represents and warrants to the
Company, as of the date hereof, the following:

     (a) the Investor is a corporation duly organized and validly existing under
the laws of the State of Delaware, and has full power and authority to enter
into, execute and perform this Agreement, which Agreement, once executed by the
Investor, shall be the valid and binding obligation of such party, enforceable
against such party by any court of competent jurisdiction in accordance with its
terns;

     (b) the individuals signing this Agreement on behalf of the Investor are
the duly elected executive officers of the Investor, and have full power and
authority to enter into and execute this Agreement for and on behalf of the
Investor;

     (c) with respect to the Repayment Shares being acquired by the Investor:

          (i) the Investor is acquiring the Repayment Shares for its own
account, and not with a view toward the subdivision, resale, distribution, or
fractionalization thereof; the Investor has no contract, undertaking, or
arrangement with any person to sell, transfer, or otherwise dispose of the
Repayment Shares (or any portion thereof), and has no present intention to enter
into any such contract, undertaking, agreement or arrangement;

          (ii) the subscription for Repayment Shares by the Investor hereunder
is not the result of any form of general solicitation or general advertising;

          (iii) the Investor hereby acknowledges that: (A) the offering of the
Repayment Shares was made only through direct, personal communication between
the Investor and the Company; (B) the Investor has had full access to material
concerning the Company's planned business and operations, which material was
furnished or made available to the Investor by officers or representatives of
the Company; (C) the Company has given the Investor the opportunity to ask any
questions and obtain all additional information desired in order to verify or
supplement the material so furnished; and (D) the Investor understands and
acknowledges that

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                                       -3-


the Repayment Shares are subject to substantial restrictions upon the transfer
thereof, and that a purchaser of the Repayment Shares must be prepared to bear
the economic risk of such investment for an indefinite period;

          (iv) the Investor understands that the Repayment Shares have not been
registered under the Securities Act of 1933 (the "Act") or any state securities
act (nor passed upon by the SEC or any state securities commission), and that
the Repayment Shares may never be registered or qualified by the Investor under
federal or state securities laws solely in reliance upon an available exemption
from such registration or qualification, and hence such Repayment Shares cannot
be sold unless they are subsequently so registered or qualified, or are
otherwise subject to any applicable exemption from such registration
requirements; and

          (v) the Investor further understands and acknowledges that (A) the
Repayment Shares have not been registered with the Ohio Securities Division
under the Ohio Securities Act, or any other law or regulation, (B) may not be
resold to any person unless and until such registration has occurred or pursuant
to an exemption from registration permitted by the applicable securities laws
and regulations of the State of Ohio; and (C) that there are substantial
restrictions on transfer of the Repayment Shares, as set forth by legend on the
reverse side of every certificate evidencing the ownership of the Repayment
Shares;

     (d) the Investor is an "accredited investor" as such term is defined in
Rule 501 of Regulation D promulgated by the Securities and Exchange Commission
under the Act, or is a sophisticated investor meeting the minimum standards for
an investment in an unregistered security under Section 1301 :6-3-03 of the Ohio
Administrative Code and Section 1707.03(0) of the Ohio Revised Code; and

     (e) the Investor has been advised to consult with an attorney regarding
legal matters concerning the purchase and ownership of the Repayment Shares, and
with a tax advisor regarding the tax consequences of purchasing such Repayment
Shares.

5.   Miscellaneous Provisions.

     (a) Notices. All notices, requests, demands and other communications to be
given hereunder shall be in writing and shall be deemed to have been duly given
on the date of personal service or transmission by fax if such transmission is
received during the normal business hours of the addressee, or on the first
business day after sending the same by overnight courier service or by telegram,
or on the third business day after mailing the same by first class mail, or on
the day of receipt if sent by certified or registered mail, addressed as set
forth below, or at such other address as any party may hereafter indicate by
notice delivered as set forth in this Section 5(a):

     If to the Company:

          Nord Resources Corporation
          9947 North Calle Solano
          Tucson, AZ 85737
          Attn: Erland Anderson, President

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                                       -4-


     If to the Investor:

          Cognis Corporation
          5051 Este Creek Drive
          Cincinnati, Ohio 45232
          Attn: President

     (b) Entire Agreement. This Agreement constitutes the entire and final
agreement and understanding between the parties with respect to the subject
matter hereof and the transactions contemplated hereby, and supersedes any and
all prior oral or written agreements, statements, representations, warranties or
understandings between the parties, all of which are merged herein and
superseded hereby.

     (c) Counterparts; Facsimiles. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. Facsimiles of original
signatures shall be deemed original signatures for all purposes.

     (d) Further Documents and Acts. Each party agrees to execute such other and
further documents and to perform such other and further acts as may be
reasonably necessary to carry out the purposes and provisions of this Agreement.

     (e) Governing Law; Venue. This Agreement shall be governed by and construed
in accordance with the internal laws of the State of Arizona applicable to
contracts to be performed within that state, without giving effect to the law of
conflicts of laws applied thereby. In the event either party shall be forced to
bring any legal action to protect or defend its rights hereunder, then the
prevailing party in such proceeding shall be entitled to reimbursement from the
non-prevailing party of all fees, costs and other expenses (including, without
limitation, the reasonable expenses of its attorneys) in bringing or defending
against such action.

     (f) Severable Provisions. The provisions of this Agreement are severable,
and if anyone or more provisions is determined to be illegal, indefinite,
invalid or otherwise unenforceable, in whole or in part, by any court of
competent jurisdiction, then the remaining provisions of this Agreement and any
partially unenforceable provisions to the extent enforceable in the pertinent
jurisdiction, shall continue in full force and effect and shall be binding and
enforceable on the parties.

                    [SIGNATURES APPEAR ON THE FOLLOWING PAGE]

IN WITNESS WHEREOF, the parties have executed this Agreement as of the date and
year first written above.

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                                       -5-


THE COMPANY:

NORD RESOURCES CORPORATION:             ATTEST:


By:
    ---------------------------------   ----------------------------------------
    Erland Anderson                     Secretary
    President


THE INVESTOR:

COGNIS CORPORATION:                     ATTEST:


By:
    ---------------------------------   ----------------------------------------
Name:
      -------------------------------   ----------------------------------------
Title:                                  Secretary
       ------------------------------