ENVIRONMENTAL INDEMNITY AGREEMENT

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                                                                    EXHIBIT 4.20

                        ENVIRONMENTAL INDEMNITY AGREEMENT
                                 (JOHNSON CAMP)

THIS ENVIRONMENTAL INDEMNITY AGREEMENT (the "AGREEMENT") is made by NORD
RESOURCES CORPORATION, a Delaware corporation and successor by merger to NORD
COPPER CORPORATION whose address is P.O. Box 384, Dragoon, AZ 85609 ("NORD") in
favor of AURAMET TRADING, LLC, a Delaware limited liability company (the
"LENDER").

     WHEREAS, Lender has made a loan in the principal amount of $2,850,000 (as
amended, supplemented, refinanced, renewed, refunded or otherwise modified from
time to time, the "Loan") to Nord represented by that certain secured promissory
note, dated as of even date herewith (as amended, supplemented or otherwise
modified from time to time, the "NOTE"), pursuant to which Nord has agreed,
among other things, to make the full and punctual payment and performance when
due of the obligations and liabilities of Nord, whether direct or indirect,
absolute or contingent, due or to become due, or existing now or prior to the
date hereof or hereafter incurred, which may arise under, out of, or in
connection the Note and any other agreements relating to the Loan (together with
any and all other obligations arising under the Loan, the "OBLIGATIONS");

     WHEREAS, contemporaneously herewith and as required by the Note, and the
other transaction documents executed by the parties in connection with the Note
(collectively with the Note, the "LOAN DOCUMENTS"), Nord is delivering to Lender
a Deed of Trust, Assignment of Rents, Security Agreement and Fixture Filing
(collectively, the "DEED OF TRUST"), for the purpose of, among other things,
securing the Obligations by and through the grant to Lender of a lien against
certain premises located in Cochise County, Arizona, commonly known as the
Johnson Camp Mine, and which are more particularly described on Exhibit "A"
attached hereto (the "JOHNSON CAMP MINE"); and

     WHEREAS, the Loan Documents require Nord indemnify Lender as set forth
herein.

     NOW, THEREFORE, FOR AND IN CONSIDERATION of valuable consideration, the
receipt and sufficiency of which are acknowledged, and further in consideration
of the mutual covenants and conditions contained in this Agreement, Nord hereby
certifies, represents, and warrants to Lender, and agrees as follows:

1. As used herein, the following terms shall have the meanings specified below:

     The term "ENVIRONMENTAL LAWS" shall mean any federal, state or local law,
whether by common law, statute, ordinance, or regulation, pertaining to health,
industrial hygiene, or environmental conditions, including without limitation,
the Comprehensive Environmental Response Compensation and Liability Act of 1980,
42 U.S.C. Sections 9601, et seq. ("CERCLA"); the Resource Conservation and
Recovery Act of 1976, 42 U.S.C. Sections 6901, et seq. ("RCRA"); the Toxic
Substances Control Act of 1976, 15 U.S.C.

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$62501, et seq. ("TSCA"); the Superfund Amendments and Reauthorization Act of
1986, Title III, 42 U.S.C. Sections 11001, et seq. ("SARA"); the Clean Air Act,
42 U.S.C. Sections 7401, et seq.; the Federal Water Pollution Control Act, 33
U.S.C. Sections 1251, et seq.; the Safe Drinking Water Act, 42 U.S.C. Sections
300f, et seq.; the Solid Waste Disposal Act, 42 U.S.C. Sections 3251, et seq.;
the Arizona Environmental Quality Act, Ariz. Rev. Stat. Ann. 49-101, et seq.;
and any other federal, state or local law, common law, statute, ordinance, or
regulation now in effect or hereinafter enacted which pertains to health,
industrial hygiene, or the regulation or protection of the environment.

     The term "HAZARDOUS SUBSTANCE" shall include:

     (a) Those substances included within the definitions of "hazardous
materials," "toxic substances," or "solid waste" in CERCLA, RCRA, TSCA, SARA,
and the Hazardous Materials Transportation Act, 49 U.S.C. Sections 1801, et
seq., and in the regulations promulgated pursuant thereto;

     (b) Those substances defined as "hazardous substances" in A.R.S. 49-201 and
in rules adopted or guidelines promulgated pursuant thereto;

     (c) Those substances listed in the United States Department of
Transportation Table (49 C.F.R. 172.1010 and amendments thereto) or by the
Environmental Protection Agency as hazardous substances (40 C.F.R. Part 302 and
amendments thereto); and

     (d) All other substances, materials and wastes that are, or that become,
regulated under, or that are classified as hazardous or toxic under any
Environmental Law.

     The term "RELEASE" shall mean any releasing, spilling, leaking, pumping,
pouring, emitting, emptying, discharging, injecting, escaping, leaching,
disposing, or dumping.

2. Nord shall neither use, generate, manufacture, produce, store, or Release,
on, under or about the Johnson Camp Mine, or transfer to or from the Johnson
Camp Mine, any Hazardous Substance nor permit any third party to do so, except
in substantial compliance with all applicable Environmental Laws. Nord shall not
permit any environmental liens to be placed on any portion of the Johnson Camp
Mine.

3. Nord shall give prompt written notice to Lender at the address set forth in
the Note of:

     (a) Any proceeding, including lawsuit, investigation or settlement by or
with any federal, state or local governmental authority (including, without
limitation, the Arizona Department of Health Services, Arizona Department of
Environmental Quality or the U.S. Environmental Protection Agency) with respect
to the presence of any Hazardous Substance on the Johnson Camp Mine or the
migration thereof from or to any other property adjacent to, or in the vicinity
of, the Johnson Camp Mine;


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     (b) Nord's discovery of a violation of Environmental Laws that Nord is
legally required to report to any federal, state or local governmental authority
or the discovery of a Release of a Hazardous Substance in sufficient quantities
to be reportable under CERCLA or the Arizona Environmental Quality Act to any
federal, state or local governmental authority.

     (c) All claims made or threatened by any third party against Nord or the
Johnson Camp Mine relating to any loss or injury resulting from any Hazardous
Substance; and

     (d) Nord's discovery of any occurrence or condition on any property
adjoining or in the vicinity of the Johnson Camp Mine that could cause the
Johnson Camp Mine or any part thereof to be subject to any restrictions on its
ownership, occupancy, transferability or use under any Environmental Laws.

4. Nord shall conduct and complete all investigations, studies, sampling,
testing and all remedial, removal, and other actions necessary to clean up and
remove all Hazardous Substances in, from or affecting the Johnson Camp Mine;

     (a) In compliance with all applicable Environmental Laws;

     (b) In accordance with the orders and directives of all governmental
authorities.

5. If Lender shall ever have good reason to believe that there are Hazardous
Substances (other than those disclosed in writing to Lender) affecting any of
the Johnson Camp Mine, Lender (by their respective officers, employees, and
agents) at any time and from time to time may contract for the services of
persons (the "SITE REVIEWERS") to perform environmental site assessments ("SITE
ASSESSMENTS") on the Johnson Camp Mine for the purpose of determining whether
there exists on the Johnson Camp Mine any environmental condition that could
result in any liability, cost, or expense to the owner, occupier, or operator of
such Johnson Camp Mine arising under any Environmental Laws. The Site
Assessments may be performed at any time or times, upon reasonable notice, and
under reasonable conditions established by Nord that do not impede the
performance of the Site Assessments and do not unreasonably interfere with any
of Nord's activities or operations at the Johnson Camp Mine. The Site Reviewers
are hereby authorized to enter upon the Johnson Camp Mine for such purposes. The
Site Reviewers are further authorized to perform both above and below the ground
testing for environmental damage or the presence of Hazardous Substances on the
Johnson Camp Mine and such other tests on the Johnson Camp Mine as may be
necessary to conduct the Site Assessments in the reasonable opinion of the Site
Reviewers. Nord will supply to the Site Reviewers such historical and
operational information regarding the Johnson Camp Mine as may be reasonably
requested by the Site Reviewers to facilitate the Site Assessments and will make
available for meetings with the Site Reviewers appropriate personnel having
knowledge of such matters. On request, Lender shall make the results of such
Site Assessments fully available to Nord, which (prior to an Event of Default


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under the Loan Documents) may, at their election, participate under reasonable
procedures in the direction of such Site Assessments and the description of
tasks of the Site Reviewers. The cost of performing such Site Assessments shall
be paid by Lender. Lender agrees to keep all data and information pertaining to
the Site Assessments, and the Site Assessments themselves, confidential, and not
to disclose any such data or information to any third party (other than the
consultants preparing the Site Assessments; unless such disclosure is required
by applicable law or court order).

6. Lender shall have the right, but not the obligation, without in any way
limiting Lender's other rights and remedies under the Loan Documents, to enter
onto the Johnson Camp Mine or to take such other actions as it deems reasonably
necessary or advisable in good faith, to clean up, remove, resolve, or minimize
the impact of, or otherwise deal with, any Hazardous Substances on or affecting
the Johnson Camp Mine following receipt of any notice from any person or entity
asserting the existence of any Hazardous Substances pertaining to the Johnson
Camp Mine or any part thereof that, if true could result in an order, notice,
suit, imposition of a lien on the Johnson Camp Mine, or other action and/or
that, in Lender's reasonable and good faith opinion, could jeopardize Lender's
security under the Loan Documents. All reasonable costs and expenses paid or
incurred by Lender in the exercise of any such rights shall be paid by Nord, and
all such reasonable costs and expenses paid or incurred by Lender shall be
secured by the Loan Documents and shall be payable by Nord upon demand. All such
actions taken by Lender pursuant to this Paragraph 7 shall be in a manner so as
not to unreasonably interfere with any of Nord's activities or operations at the
Johnson Camp Mine, and shall be taken in accordance with Nord's reasonable
safety rules and regulations and any such rules and regulations imposed by any
governmental agency.

7. Lender shall have the right at any time to appear in and to participate in,
as a party if it so elects, and be represented by counsel of its own choice in,
any action or proceeding initiated in connection with any Environmental Law that
affects the Johnson Camp Mine.

8. Nord shall indemnify and hold harmless Lender, any successor to Lender, any
purchaser of the Johnson Camp Mine upon foreclosure of Lender's interest in the
Johnson Camp Mine, and all directors, officers, employees and agents of all of
the foregoing, from and against all claims, costs, expenses, actions, suits,
proceedings, losses, damages and liabilities of any kind whatsoever, including
but not limited to attorneys' fees and expenses, directly or indirectly arising
out of or attributable to (i) the use, generation, manufacture, production,
storage, Release, threatened Release, or presence of a Hazardous Substance on,
under or about the Johnson Camp Mine occurring from and after the closing of the
sale of the Johnson Camp Mine to Nord and not substantially arising out of or
substantially related to any material action or omission to act by Lender; (ii)
any violation or claim of violation of any Environmental Law with respect to the
Johnson Camp Mine, and not substantially arising out of or substantially related
to any material action or omission to act by Lender; or (iii) any material
breach of any of the warranties, representations and covenants contained herein.
Lender shall give written notice to Nord promptly of any claim, suit, action,
the commencement of any proceeding


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or demand of which Lender has received written notice from a third party and as
to which Lender believes it may be entitled to indemnification hereunder.

9. This Agreement shall be binding upon Nord and its successors and assigns and
shall inure to the benefit of Lender, their respective successors and assigns.
The indemnity contained herein shall continue in full force and effect and shall
survive the payment and performance of the Note, the release of any lien or
encumbrance securing the Note, any foreclosure (or action in lieu of
foreclosure) of any lien or encumbrance securing the Note, the exercise by
Lender of any other remedy under any documents securing the Note, and any suit,
proceeding or judgment against Nord by Lender hereon.

10. If any material warranty, representation or statement contained herein shall
be or shall prove to have been false when made or if Nord shall fail or neglect
to perform or observe any of the terms, provisions or covenants contained
herein, the same shall constitute an Event of Default under the Note and under
all documents and instruments executed and delivered in connection therewith
that shall entitle Lender to pursue any and all remedies provided for such
default.

11. Any notice required or permitted in connection herewith shall be given in
the manner provided in the Note or other documents executed and delivered in
connection with the Note.

12. Nord acknowledges that Lender has and will rely upon the representations,
warranties and agreements herein set forth in closing and funding (or modifying
as the case may be) the Note and that the execution and delivery of this
Agreement is an essential condition but for which Lender would not have agreed
to loan Nord the funds as set forth in the Note.

13. Nord waives any right or claim of right to cause a marshaling of the assets
of Nord or to cause Lender to proceed against any of the security for the Note
before proceeding under this Agreement against Nord; Nord agrees that any
payments required to be made hereunder shall become due on demand; Nord
expressly waives and relinquishes all rights and remedies accorded by applicable
law to Nord or guarantors (including, without limitation, A.R.S. Sections
12-1641, et seq., and 44-142, and Rule 17f of the Arizona Revised Statutes Rules
of Civil Procedure), except any rights of subrogation that Nord may have,
provided that the indemnity provided for hereunder shall neither be contingent
upon the existence of any such rights of subrogation nor subject to any claims
or defenses whatsoever that may be asserted in connection with the enforcement
or attempted enforcement of such subrogation rights, including, without
limitation, any claim that such subrogation rights were abrogated by any acts or
omissions of Lender.

14. This Agreement shall be governed by and construed according to the laws of
the State of Arizona, without giving effect to conflict of laws principles.


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     IN WITNESS WHEREOF, Nord has executed this Agreement on October 17th, 2005.

                                        NORD RESOURCES CORPORATION, a
                                        Delaware corporation and successor by
                                        merger to NORD COPPER CORPORATION


                                        By: /s/ Erland A. Anderson
                                            ------------------------------------
                                        Name: Erland A. Anderson
                                        Title: President

STATE OF ARIZONA   )
                   ) ss.
County of Pima     )

The foregoing instrument was acknowledged before me this day of October 17th,
2005 by Erland A. Anderson, the President of NORD RESOURCES CORPORATION, a
Delaware corporation and the successor by merger to NORD COPPER CORPORATION, on
behalf of the corporation.

     IN WITNESS WHEREOF, I hereunto set my hand and official seal.


                                        /s/ Madelyn L. Swingle
                                        ----------------------------------------
                                        Notary Public

My commission expires:
6-14-09


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                                   EXHIBIT "A"

The following property located in Cochise County, Arizona, together with all
extralateral rights, water rights, and appurtenances, and all fixtures,
stockpiles, leach heaps, dumps, and tailings situated thereon:

                         Part 1 - Patented Mining Claims

PARCEL 1

     Arizona, Blue Grass, Puzzle, Enough, and Canton patented lode mining
claims, Mineral Survey No. 4340, embracing a portion of Section 23, Township 15
South, Range 22 East, G&SRB&M, in the Cochise Mining District, Cochise County,
Arizona, U.S. Patent No. 1143496, recorded in the records of Cochise County at
Docket 100, Page 283,

     EXCEPT all that portion of the ground within the boundaries of Ross, Dewey,
and True Blue, Mineral Survey No. 1717, and North Star, Mineral Survey No. 3242;
and further except all veins, lodes, and ledges, throughout their entire depth,
the tops or apexes of which lie inside the said excluded ground,

     containing 66.721 acres, more or less.

PARCEL 2

     Afterthought, Burro, Burro No. 3, Coronado, Coronado No. 2, and Mason No. 1
patented lode mining claims, Mineral Survey No. 4571, embracing portions of
Sections 25, 26, and 35, Township 15 South, Range 22 East, G&SRB&M, in the
Cochise Mining District, Cochise County, Arizona, U.S. Patent No. 02-63-0060,
recorded in the records of Cochise County at Docket 315, Page 561,

     EXCEPT all that portion of the ground within the boundaries of Republic,
Mineral Survey No. 324; Golden Shield, Mineral Survey No. 325; Chicora, Mineral
Survey No. 326; Southern, Mineral Survey No. 327; Mayflower, Mineral Survey No.
2764; Calumet, Mineral Survey No. 4197; Tenderfoot, Mineral Survey No. 4314; and
Section 36, Township 15 South, Range 22 East; and further except all veins,
lodes, and ledges, throughout their entire depth, the tops or apexes of which
lie inside the said excluded ground,

     containing 89.005 acres, more or less.

PARCEL 3

     St. George patented lode mining claim, Mineral Survey No. 1966, embracing a
portion of Section 36, Township 15 South, Range 22 East, G&SRB&M, in the Cochise
Mining District, Cochise County, Arizona, U.S. Patent No. 42949, recorded in the
records of Cochise County at Book 20, Deeds of Mines, Page 312,

     containing 17.732 acres, more or less.


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PARCEL 4

     Mayflower (aka May Flower) patented lode mining claim, Mineral Survey No.
2764, embracing portions of Sections 25 and 26, Township 15 South, Range 22
East, G&SRB&M, in the Cochise Mining District, Cochise County, Arizona, U.S.
Patent No: 298716, recorded in the records of Cochise County at Docket 12, Page
581,

     containing 19.414 acres, more or less.

PARCEL 5

     Acorn, A-Number One, A-Number Two, Chicago, Cochise, Copper Thread,
Johnson, Little Johnnie, Rough Rider, Tenderfoot, and United Fraction patented
lode mining claims, Mineral Survey No. 4314, embracing portions of Sections 23,
25, and 26, Township 15 South, Range 22 East, G&SRB&M, in the Cochise Mining
District, Cochise County, Arizona, U.S. Patent No. 1141449, recorded in the
records of Cochise County at Docket 93, Page 620,

     EXCEPT all that portion of the ground within the boundaries of Blue Lead
Extension, Dwarf, Esmeralda, and Copper Chief, Mineral Survey No. 3242; Copper
Bell, Mineral Survey 1717; Highland Mary, Mineral Survey No. 284; Copper King,
Mineral Survey No. 285; Republic, Mineral Survey No. 324; Golden Shield, Mineral
Survey No. 325; Mayflower, Mineral Survey No. 2764; Tycoon, Mineral Survey No.
329; and Gingham No. 3, unsurveyed; and further except all veins, lodes, and
ledges, throughout their entire depth, the tops or apexes of which lie inside
the said excluded ground,

     FURTHER EXCEPT those portions of Cochise and United Fraction, containing
0.026 and 0.387 acres, more or less, respectively, being those portions lying in
the Southeast Quarter of the Northwest Quarter (SE1/4NW1/4) and the Northeast
Quarter of the Southwest Quarter (NE1/4SW1/4) of Section 25, Township 15 South,
Range 22 East, G&SRB&M, conveyed by Special Warranty Deed dated January 26, 1987
from Cyprus Mines Corporation, Grantor, to David Rae, Grantee, recorded in the
Cochise County records as document No. 870102364,

     containing 106.572 acres, more or less.

PARCEL 6

     Blue Lead, North Star, Little Bush, Copper Chief, Southern Cross, Blue Lead
Extension, Dwarf, and Esmeralda patented lode mining claims, Mineral Survey No.
3242, embracing portions of Sections 23 and 26, Township 15 South, Range 22
East, G&SRB&M, in the Cochise Mining District, Cochise County, Arizona, U.S.
Patent No. 610053, recorded in the records of Cochise County at Book 29, Deeds
of Mines, Page 92,

     containing 92.563 acres, more or less.


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PARCEL 7

     Anaconda, Last Chance, Delta, and Sara patented lode mining claims, Mineral
Survey No. 1525, embracing portions of Sections 23 and 24, Township 15 South,
Range 22 East, G&SRB&M, in the Cochise Mining District, Cochise County, Arizona,
U.S. Patent No. 036147, recorded in the records of Cochise County at Book 15,
Deeds of Mines, Page 236,

     containing 54.14 acres, more or less.

PARCEL 8

     Southern patented lode mining claim, Lot 45, Mineral Survey No. 327,
embracing portions of Sections 25, 26, and 36, Township 15 South, Range 22 East,
G&SRB&M, in the Cochise Mining District, Cochise County, Arizona, U.S. Patent
No. 9043 (or 9143), recorded in the records of Cochise County at Book 31, Deeds
of Mines, Page 459,

     containing 18.79 acres, more or less.

PARCEL 9

     Mi-an-te-no-mah patented lode mining claim, Lot 48, Mineral Survey No. 330,
embracing a portion of Section 23, Township 15 South, Range 22 East, G&SRB&M, in
the Cochise Mining District, Cochise County, Arizona, U.S. Patent No. 10723,
recorded in the records of Cochise County at Book 31, Deeds of Mines, Page 455,

     containing 19.28 acres, more or less.

PARCEL 10

     Peabody patented lode mining claim, Lot 39, Mineral Survey No. 286,
embracing portions of Sections 23 and 24, Township 15 South, Range 22 East,
G&SRB&M, in the Cochise Mining District, Cochise County, Arizona, U.S. Patent
No. 6424, recorded in the records of Cochise County at Book 12, Deeds of Mines,
Page 433,

     containing 17.36 acres, more or less.

PARCEL 11

     Donna Anna patented lode mining claim, Lot 40, Mineral Survey No. 287,
embracing a portion of Section 26, Township 15 South, Range 22 East, G&SRB&M, in
the Cochise Mining District, Cochise County, Arizona, U.S. Patent No. 6423,
recorded in the records of Cochise County. at Book 31, Deeds of Mines, Page 427,

     containing 20.66 acres, more or less.


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PARCEL 12

     Highland Mary patented lode mining claim, Lot 37, Mineral Survey No. 284,
embracing portions of Sections 25 and 26, Township 15 South, Range 22 East,
G&SRB&M, in the Cochise Mining District, Cochise County, Arizona, U.S. Patent
No. 6474, recorded in the records of Cochise County at Book 31, Deeds of Mines,
Page 431,

     EXCEPT all that portion of Highland Mary containing 0.064 acres, more or
less, being that portion lying in the Southeast Quarter of the Northwest Quarter
(SE1/4NW1/4) of Section 25, Township 15 South, Range 22 East, G&SRB&M, conveyed
by Special Warranty Deed dated January 26, 1987 from Cyprus Mines Corporation,
Grantor, to David A. Rae, Grantee, recorded in the Cochise County records as
Document No. 870102364,

     containing 20.596 acres, more or less.

PARCEL 13

     Copper King patented lode mining claim Lot 38, Mineral Survey No. 285,
embracing a portion of Section 26, Township 15 South, Range 22 East, G&SRB&M, in
the Cochise Mining District, Cochise County, Arizona, U.S. Patent No. 6475,
recorded in the records of Cochise County at Book 31, Deeds of Mines, Page 435,

     containing 20.11 acres, more or less.

PARCEL 14

     Golden Shield patented lode mining claim, Lot 43, Mineral Survey No. 325,
embracing a portion of Section 26, Township 15 South, Range 22 East, G&SRB&M, in
the Cochise Mining District, Cochise County, Arizona, U.S. Patent No. 8891,
recorded in the records of Cochise County at Book 31, Deeds of Mines, Page 439,

     containing 19.51 acres, more or less.

PARCEL 15

     Republic patented lode mining claim, Lot 42, Mineral Survey No. 324,
embracing a portion of Section 26, Township 15 South,