Copperstone

The Copperstone is a gold mine located in La Paz county, Arizona at an elevation of 879 feet.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Copperstone

Commodity

Primary: Gold
Tertiary: Silver
Tertiary: Barium-Barite

Location

State: Arizona
County: La Paz
District: Moon Mountains District, La Paz District

Land Status

Land ownership: BLM Administrative Area
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

Holdings

Not available

Workings

Type: Surface

Ownership

Owner Name: Cyprus Minerals Corp. , Don Patch Retains Royalty Rights
Years: 1988 -

Owner Name: Morrison-Knudsen
Years: 1989 -

Production

Not available

Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1987
Discovery Year: 1979
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: M

Physiography

General Physiographic Area: Intermontane Plateaus
Physiographic Province: Basin And Range Province
Physiographic Section: Sonoran Desert

Mineral Deposit Model

Not available

Orebody

Form: TABULAR

Structure

Type: R
Description: Moon Mountains Detachment Fault

Type: L
Description: Probable Fault Separating Jurassic Metamorphosed Volcanic Rocks And Overlying Sedimentary Breccias Derived From Them.

Alterations

Alteration Type: L
Alteration Text: Sericitization, Some Chloritization

Rocks

Name: Volcanic Breccia (Agglomerate)
Role: Host
Age Type: Host Rock
Age Young: Late Jurassic

Analytical Data

Not available

Materials

Ore: Gold
Ore: Chalcopyrite
Ore: Pyrite
Gangue: Quartz
Gangue: Amethyst
Gangue: Calcite
Gangue: Magnetite
Gangue: Fluorite
Gangue: Chrysocolla
Gangue: Barite
Gangue: Malachite

Comments

Comment (Location): SITE CONSISTS OF 290 UNPATENTED MINING CLAIMS LEASED BY CYPRUS, COVERING 5800 ACRES OF FEDERAL LAND. INFO FROM LAND.ST :(1992)

Comment (Commodity): PRESENCE OF QUARTZ, HEMATITE, AND CHRYSOCOLLA IS A GOOD INDICATOR OF GOLD MINERALIZATION.

Comment (Development): LIFE OF PROJECT IS ESTIMATED AT 7-9 YEARS. NO PREVIOUS MINING OCCURRED AT THIS SITE. UNDERGROUND DEVELOPMENT WAS STOPPED BY CYPRUS IN 1990 DUE TO LOWER GOLD PRICES AND BECAUSE OF CAVING GROUND CONDITIONS WHICH REQUIRED COSTLY SUPPORT METHODS. CYPRUS MAY CONSIDER REACHING THE FORMER UNDERGROUND MINING TARGETS FROM THE SURFACE. ; TOTAL$: 25 ; MILL$: 13.9 ; ECON.YEAR: 1987 ; ECON.COM: TOTAL WORK FORCE OF ABOUT 105, WITH 65 CONTRACT MINERS FOR M-K AND 40 CYPRUS EMPLOYEES; PRODUCTION COSTS ARE ABOUT $200 PER OZ ; MILL.CAP : 2500 T/D

Comment (Deposit): GOLD IN A BRECCIA UNIT ABOVE A LISTRIC FAULT, IN QUARTZ LATITE BELOW THE LISTRIC FAULT, AND IN BASALT PLUGS. THE BASALT PLUGS HAVE THE LEAST MINERALIZATION. THE LISTRIC FAULT IS IN THE UPPER PLATE OF A DETACHMENT FAULT. THE MINERALIZED CONTACT ZONE EXTENDS HORIZONTALLY FOR 3,000 FT AND AT LEAST 1,000 FT DOWN DIP AND IS GENERALLY SEVERAL TENS OF FT THICK.

Comment (Workings): THE BENCH OPEN PIT WILL BE 360 FT DEEP.

Comment (Geology): FRACTURE AND FAULT FILLING WITH HYDROTHERMAL BRECCIATION OF QUARTZ LATITES.

Comment (Production): COPPERSTONE WILL BE THE LARGEST GOLD PRODUCER IN ARIZONA AND WILL MORE THAN DOUBLE THE STATE'S 1986 GOLD OUTPUT OF 42,556 OZ.

References

Reference (Deposit): PETERSON, E.K., AND DUPREE, J.A., 1993, PRELIMINARY INVESTIGATION OF BULK MINABLE GOLD DEPOSITS, COLORADO RIVER INDIAN RESERVATION, ARIZONA AND CALIFORNIA, IN MANYDEEDS, S.A., AND SMITH, B.D., EDS., MINERAL FRONTIERS ON INDIAN LANDS: BUREAU OF INDIAN AFFAIRS DIVISION OF ENERGY AND MINERAL RESOURCES, P. 35-42.

Reference (Deposit): NIEMUTH, N.J., 1987, ARIZONA MINERAL DEVELOPMENT 1984-1986: ARIZONA DEPARTMENT OF MINES AND MINERAL RESOURCES DIRECTORY 29, 46 P.

Reference (Deposit): SAWYER, M.B., GURMENDI, A.C., DALEY, M.R., AND HOWELL, S.B., 1992, PRINCIPAL DEPOSITS OF STRATEGIC AND CRITICAL MINERALS IN ARIZONA: UNITED STATS BUREAU OF MINES SPECIAL PUBLICATION, 334 P.

Reference (Deposit): MINERAL TODAY, 1/90, P. 26.

Reference (Other Database): CIMRI

Reference (Production): WALENGA, 1987, P. 4A; SAWYER AND OTHERS, 1992; MINERAL TODAY, 1990.

Reference (Reserve-Resource): WALENGA, 1988, P. 5A; NIEMUTH, 1987.

Reference (Deposit): WALENGA, KAREN, 1987, NEW OPERATION TO DOUBLE ARIZONA GOLD PRODUCTION: SOUTHWESTERN PAY DIRT, NO. 581, P. 4A-5A.

Reference (Deposit): WALENGA, KAREN, 1988, CYPRUS STARTS WORK ON UNDERGROUND MINE AT COPPERSTONE: SOUTHWESTERN PAYDIRT, NO. 592, P. 5A.

Reference (Deposit): SPENCER, J.E., DUNCAN, J.T., AND BURTON, W.D., 1988, THE COPPERSTONE MINE: ARIZONA'S NEW GOLD PRODUCER: ARIZONA BUREAU OF GEOLOGY AND MINERAL TECHNOLOGY FIELDNOTES, V. 18, NO. 2, P. 1-3.

Arizona Gold

"Where to Find Gold in Arizona" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in Arizona. Read more: Where to Find Gold in Arizona.