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                                                                     EXHIBIT 4.5

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A
VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO SUCH SALE
OR DISTRIBUTION MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT
RELATED THERETO OR AN OPINION OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY
THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OF 1933.

                           CONVERTIBLE PROMISSORY NOTE

                                   ----------

October 4, 2004

     For value received, Nord Resources Corporation, a Delaware corporation (the
"Company"), promises to pay to Ronald A. Hirsch (the "Holder"), the principal
sum of One Hundred Six Thousand Dollars and no Cents ($106,000.00). Simple
interest shall accrue from the date of this Note on the unpaid principal amount
at a rate equal to ten percent (10 %) per annum. This Note is subject to the
following terms and conditions:

     1. Maturity. Unless converted as provided in Section 2, this Note will
automatically mature and be due and payable on October 5, 2005 (the "Maturity
Date"). Subject to Section 2 below, interest shall accrue on this Note.

     2. Conversion.

          (a) Investment by the Holder. On the Maturity Date, some or all of the
          entire principal amount of and (at the Company's option) accrued
          interest on this Note may be converted into shares of the Company's
          equity securities. The conversion price shall be Twenty Cents ($0.20)
          per share.

          (b) Mechanics and Effect of Conversion. No fractional shares of the
          Company's capital stock will be issued upon conversion of this Note.
          In lieu of any fractional share to which the Holder would otherwise be
          entitled, the Company will pay to the Holder in cash the amount of the
          unconverted principal and interest balance of this Note that would
          otherwise be converted into such fractional share. Upon conversion of
          this Note pursuant to this Section 2, the Holder shall surrender this
          Note, duly endorsed, at the principal offices of the Company. At its
          expense, the Company will, as soon as practicable thereafter, issue
          and deliver to such Holder, at such principal office, a certificate or
          certificates for the number of shares to which such Holder is entitled
          upon such conversion, together with an other securities and property
          to which the Holder is entitled upon such conversion under the terms
          of this Note, including a check payable to the Holder for any cash
          amounts payable as described herein. Upon conversion of this Note, the
          Company will be forever released from all of its obligations and
          liabilities under this Note with regard to that portion of the
          principal amount and accrued interest being converted including
          without limitation the obligation to pay such portion of the principal
          amount and accrued interest.


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     3. Payment. All payments shall be made in lawful money of the United States
of America at such place as the Holder hereof may from time to time designate in
writing to the Company. Payment shall be credited first to the accrued interest
then due and payable and the remainder applied to principal. Prepayment of any
part of this Note or the entire amount of this Note may be made at any time
without penalty.

     4. Transfer; Successors and Assigns. The terms and conditions of this Note
shall inure to the benefit of and be binding upon the respective successors and
assigns of the parties. Notwithstanding the foregoing, the Holder may not
assign, pledge, or otherwise transfer this Note without the prior written
consent of the Company, except for transfers to affiliates. Subject to the
preceding sentence, this Note may be transferred only upon surrender of the
original Note for registration of transfer, duly endorsed, or accompanied by a
duly executed written instrument of transfer in form satisfactory to the Holder.
Thereupon, a new note for the same principal amount and interest will be issued
to, and registered in the name of, the transferee. Interest and principal are
payable only to the registered holder of this Note.

     5. Governing Law. This Note and all acts and transactions pursuant hereto
and the rights and obligations of the parties hereto shall be governed,
construed and interpreted in accordance with the laws of the State of Arizona,
without giving effect to principles of conflicts of law.

     6. Notices. Any notice required or permitted by this Note shall be in
writing and shall be deemed sufficient upon delivery, when delivered personally
or by a nationally-recognized delivery service (such as Federal Express or UPS),
or forty-eight (48) hours after being deposited in the U.S. Mail, as certified
or registered mail, with postage prepaid, addressed to the party to be notified
at such party's address as set forth below or as subsequently modified by
written notice.

     7. Amendments and Waivers. Any term of this Note may be amended only with
the written consent of the Company and the Holder. Any amendment or waiver
effected in accordance with this Section 7 shall be binding upon the Company,
the Holder and each transferee of the Note.

     8. Stockholders, Officers and Directors Not Liable. In no event shall any
stockholder, officer or director of the Company be liable for any amounts due or
payable pursuant to this Note.

     9. Entire Agreement. This Agreement, together with any exhibits attached
hereto, constitutes the entire understanding and agreement of the parties
hereto. This Agreement supersedes all prior negotiations, discussions,
correspondence, communications, understandings and agreements between the
parties relating to the subject matter of this Agreement.

     10. 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 containing original signatures shall be
deemed for all purposes to be originally-signed copies of the documents which
are the subject of such facsimiles.

                  [SIGNATURES TO APPEAR ON THE FOLLOWING PAGE]


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AGREED TO AND ACCEPTED:

COMPANY:

NORD RESOURCES CORPORATION


By: /s/ Erland A. Anderson
    ---------------------------------
Name: Erland A. Anderson
Title: President
Address: 3048 N. Seven Dash Road,
         PO Box 384 Dragoon,
         Arizona 85609


HOLDER:

RONALD A. HIRSCH


By: /s/ Ronald A. Hirsch
    ---------------------------------
Name: Ronald A. Hirsch
Address: 668 N. Coast, Apt #171
         Laguna Beach, CA 92051


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