Commonwealth Mine

Site Name

Primary: Commonwealth Mine
Secondary: Pearce Mine
Secondary: Includes Eisenhart Vein
Secondary: North
Secondary: Rinaud
Secondary: Smith
Secondary: Footwa Ll
Secondary: Main
Secondary: Extension
Secondary: Ritter
Secondary: Brockman
Secondary: Hartery Veins
Secondary: Discovery Stope

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Commodity

Primary: Silver
Primary: Silica
Primary: Gold
Tertiary: Molybdenum
Tertiary: Copper
Tertiary: Lead
Tertiary: Vanadium

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Location

State: Arizona
County: Cochise
District: Pearce District

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Land Status

Land ownership: Private
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.

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Holdings

Not available

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Workings

Type: Underground

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Ownership

Owner Name: C. O. R. Ford Corp.
Home Office: Dallas, Tx.
Years: 1979 -

Owner Name: Phelps Dodge Corp.
Years: 1987 -

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Production

Not available

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Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1895
Year Last Production: 1979
Discovery Year: 1895
Years of Production:
Organization:
Significant: Y
Deposit Size: S

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Physiography

General Physiographic Area: Intermontane Plateaus
Physiographic Province: Basin And Range Province
Physiographic Section: Mexican Highland

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Mineral Deposit Model

Not available

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Orebody

Form: TABULAR, STRINGERS, MASSIVE

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Structure

Type: R
Description: Flows Dip 35-40e

Type: L
Description: Fissure Veins And Fault Breccia Zones; N-S Faults Are Premineraliz Ation, Others Are Postmineralization

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Alterations

Alteration Type: L
Alteration Text: Propylitic, Silicification, Oxidation; Alteration More Intense In And Near Vein Fractures. Sericitic And K-Spar Alteration Closest To The Veins, With Extensive Argillic And Propylitic Alteration Away From The Veins.

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Rocks

Name: Rhyolite
Role: Associated
Age Type: Associated Rock
Age Young: Pliocene

Name: Rhyolite
Role: Associated
Age Type: Host Rock
Age Young: Pliocene

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Analytical Data

Not available

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Materials

Ore: Silver
Ore: Cerargyrite
Ore: Tetrahedrite
Ore: Chalcopyrite
Ore: Galena
Ore: Chalcocite
Ore: Iodyrite
Ore: Argentite
Ore: Chrysocolla
Ore: Gold
Ore: Molybdenite
Ore: Embolite
Ore: Wulfenite
Ore: Proustite
Ore: Pyrite
Gangue: Hematite
Gangue: Sericite
Gangue: Fluorite
Gangue: Gypsum
Gangue: Jarosite
Gangue: Limonite
Gangue: Kaolin
Gangue: Rhodochrosite
Gangue: Alunite
Gangue: Calcite
Gangue: Siderite
Unknown: Quartz

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Comments

Comment (Reserve-Resource): KEITH REPORTED THAT UP TO A MILLION TONS OF TAILINGS REMAIN AND THAT IN ADDITION APPROXIMATELY 150,000 TONS OF MINE DUMP MATERIAL IN THE AREA THAT AVERAGES 2.5 OZ OF AG/T. NIEMUTH (1987) REPORTS THAT THE OPENP PIT RESERVES ARE ONLY PARTIALLY DRILLED. THE UNDERGROUND FIGURE IS FOR DRILLED RESERVES.

Comment (Location): INFO FROM LAND.ST :(1992)

Comment (Production): IN RECENT YEARS THERE HAVE BEEN SPORADIC SHIPMENTS OF TAILINGS TO THE HIDALGO SMELTER AT PLAYAS, NEW MEXICO. SO FAR, ABOUT 100,000 TONS OF TAILINGS HAVE BEEN SOLD FOR USE AS HIGH-SILICA SMELTER FLUX. IT IS ESTIMATED THAT UP TO A MILLION TONS OF TAILINGS REMAIN. IN ADDITION THERE ARE APPROXIMATELY 150,000 TONS OF MINE DUMP MATERIAL IN THE AREA THAT AVERAGE 2.5 OZ OF AG/T.

Comment (Development): OPERATORS HAVE INCLUDED COMMONWEALTH MINING AND MILLING CO, MONTANA TO NOPAH MINING & MILLING CO, COMMONWEALTH DEVELOPMENT CO, GOURMET CHIEF INC. (1975). TAILINGS BEING REWORKED, 1976-79, FLOTATION METHODS. IN MID-1980'S MADE INTERMITTENT SHIPPINGS OF TAILINGS.

Comment (Deposit): IRREGULAR AG-AU HALIDES AND MNOR SULFO-SALTS WITH SOME MANGANESE IN QUARTZ-CALCITE FISSURE VEINS AND IN FAULT BRECCIA ZONES IN SILICIFIED TERTIARY RHYOLITE AND ANDESITE.

Comment (Workings): LENGTH OF WORKINGS ESTIMATED FROM MINE MAPS; TWO INCLINED SHAFTS, 62 DEG, WITH EXTENSIVE WORKINGS ON 8 LEVELS. THE WATER LEVEL WAS AT 700 FT, AND A MAJORITY OF MINING WAS DONE ABOVE THE WATER-TABLE, ALTHOUGH SHAFT "C" WAS EVENTUALLY SUNK TO 1,000 FT. THERE ARE ABOUT 20 MILES OF UNDERGROUND WORKINGS.

Comment (Geology): ONE OF ARIZONA'S MAJOR SILVER PRODUCERS.

Comment (Deposit): THIS REPORT WAS MODIFIED FROM RECORD M030569 OF JAN WILT IN MOLYBDENUM FILE, CONTACT PERSON T.G. THEODORE, USGS. ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

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References

Reference (Deposit): SCOTT, 1916, MINING AND ENGINEERING WORLD, V. 45, P. 187-188.

Reference (Deposit): HOWELL, 1977, MS. THESIS, UNIVERSITY OF ARIZONA.

Reference (Deposit): SMITH, 1927, MS THESIS, UNIVERSITY OF ARIZONA.

Reference (Deposit): ADMR FILE DATA

Reference (Deposit): KEITH, 1973, ABM BULL 187.

Reference (Deposit): ABM FILE DATA.

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 (Other Database): CIMRI

Reference (Production): KEITH, 1973, P. 69; HEYLMUN, 1988, P. 16; SAWYER AND OTHERS, 1992.

Reference (Reserve-Resource): NIEMUTH, 1987.

Reference (Deposit): HEYLMUN, E.B., 1988, COMMONWEALTH SILVER-GOLD MINE, ARIZONA: CALIFORNIA MINING JOURNAL, V. 57, NO. 5, P. 14-16.

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

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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.