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                                                                    EXHIBIT 4.16

                             SECURED PROMISSORY NOTE

$600,000.00                                                          Dragoon, AZ
                                                                   June 21, 2005

This Secured Promissory Note (the "Note") is made and executed as of the date
referred to above, by and between Nord Resources Corporation, a Delaware
corporation (the "Borrower"), and Ronald A. Hirsch and Stephen Seymour
(collectively, "Lender"). By this Note, the Borrower promises and agrees to pay
to the order of Lender the principal sum of Six Hundred Thousand Dollars
($600,000.00), or the aggregate unpaid principal amount of all advances made by
Lender to Borrower pursuant to the terms of a Revolving Line of Credit Agreement
(the "Loan Agreement ") and a Security Agreement (the "Security Agreement") of
even date herewith, whichever is less, together with interest thereon from the
date each advance is made until paid in full, both before and after judgment, at
the rate of six percent (6%) per annum, simple interest.

The entire unpaid principal balance, together with any accrued interest and
other unpaid charges or fees hereunder, shall be due and payable on December 31,
2005, (the "Maturity Date").

Prepayment in whole or part may occur at any time hereunder without penalty;
provided that the Lender shall be provided with not less than ten (10) days
notice of the Borrower's intent to pre-pay; and provided further that any such
partial prepayment shall not operate to postpone or suspend the obligation to
make, and shall not have the effect of altering the time for payment of the
remaining balance of the Note as provided for above, unless and until the entire
obligation is paid in full. All payments received hereunder shall be applied,
first, to any costs or expenses incurred by Lender in collecting such payment or
to any other unpaid charges or expenses due hereunder; second, to accrued
interest; and third, to principal.

An event of default will occur if any of the following events occurs: (a)
failure to pay any principal or interest hereunder within ten (10) days after
the same becomes due; (b) if any representation or warranty made by Borrower in
the Loan Agreement or in connection with any borrowing or request for an advance
thereunder, or in any certificate, financial statement, or other statement
furnished by Borrower to Lender is untrue in any material respect at the time
when made; (c) default by Borrower in the observance or performance of any other
covenant or agreement contained in the Loan Agreement or Security Agreement, (d)
filing by Borrower of a voluntary petition in bankruptcy seeking reorganization,
arrangement or readjustment of debts, or any other relief under the Bankruptcy
Code as amended or under any other insolvency act or law, state or federal, now
or hereafter existing; or (e) filing of an involuntary petition against Borrower
in bankruptcy seeking reorganization, arrangement or readjustment of debts, or
any other relief under the Bankruptcy Code as amended, or under any other
insolvency act or law, state or federal, now or hereafter existing, and the
continuance thereof for sixty (60) days undismissed, unbonded, or undischarged.


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Any notice or demand to be given to the parties hereunder shall be deemed to
have been given to and received by them and shall be effective when personally
delivered or when deposited in the U.S. mail, certified or registered mail,
return receipt requested, postage prepaid, and addressed to the party at his or
its last known address, or at such other address as the one of the parties may
hereafter designate in writing to the other party.

The Borrower hereof waives presentment for payment, protest, demand, notice of
protest, notice of dishonor, and notice of nonpayment, and expressly agrees that
this Note, or any payment hereunder, may be extended from time to time by the
Lender without in any way affecting its liability hereunder.

In the event any payment under this Note is not made at the time and in the
manner required, the Borrower agrees to pay any and all costs and expenses which
may be incurred by the Lender hereof in connection with the enforcement of any
of its rights under this Note or under any such other instrument, including
court costs and reasonable attorneys' fees.

This Note shall be governed by and construed and enforced in accordance with the
laws of California.

The Borrower:

NORD RESOURCES CORPORATION,
A Delaware corporation


/s/ Erland A. Anderson
-------------------------------------
By: Erland A. Anderson
Its: President


The Lender:


/s/ Ronald A. Hirsch
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Ronald A. Hirsch, an individual


/s/ Stephen Seymour
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Stephen Seymour, an individual


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