Twin Buttes

The Twin Buttes is a copper sulfide, copper oxide, and copper mine located in Pima county, Arizona at an elevation of 3,353 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

Name: Twin Buttes

State: Arizona

County: Pima

Elevation: 3,353 Feet (1,022 Meters)

Commodity: Copper Sulfide, Copper Oxide, Copper

Lat, Long: 31.9081, -111.05000

Map: View on Google Maps

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.

Satelite image of the Twin Buttes

Twin Buttes MRDS details

Site Name

Primary: Twin Buttes
Secondary: Copper Butte Mine

Commodity

Primary: Copper Sulfide
Primary: Copper Oxide
Primary: Copper
Secondary: Lead
Secondary: Silver
Secondary: Molybdenum
Secondary: Gold
Tertiary: Wollastonite
Tertiary: Uranium
Tertiary: Zinc

Location

State: Arizona
County: Pima
District: Pima District

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.

Holdings

Type: Located Claim
Type: Patented

Workings

Type: Surface

Ownership

Owner Name: Freeport-McMoran Copper and Gold
Percent: 100.0
Home Office: Arizona
Info Year: 2009
Years: 2006 -

Owner Name: Phelps Dodge Corp
Percent: 100.0
Info Year: 2009
Years: 1999 - 2006

Owner Name: Anamax Company
Percent: 100.0
Years: 1973 - 1985

Owner Name: Banner Mining Company
Percent: 100.0
Years: 1950 - 1973

Owner Name: Park Corp.
Company ID: 200136
Percent: 100.0
Home Office: West Virginia
Info Year: 1991

Owner Name: Cyprus Amax Corp.
Company ID: 200136
Percent: 100.0
Home Office: Arizona
Info Year: 1991
Years: 1985 - 1999

Production

Year: 1989
Description: Oxide Ore Treated 1103000 Year: 1990
Description: Oxide Ore Treated 753000 Year: 1992
Time Period: 1969-1992
Mined: 183416000.00 mt
Material type: 16,828 tonnes molybdenum; Year: 1990
Description: Sulfide Ore Treated 5198000 Year: 1989
Description: Sulfide Ore Treated 2553000 Year: 1988
Description: Oxide Ore Treated 1124000 Year: 1985
Description: Mine, Sulfide & Oxide Plants Permanently Year: 1985
Description: Produced At Oxide Plant Year: 1985
Description: Mine Closed - Cu Oxide Stockpiled Ore Year: 1984
Description: Mo Byproduct Plant Closed Year: 1984
Description: Oxide Plant Closed For 1984 Year: 1984
Description: Only Cu Recovered From Stockpiled Ore Year: 1984
Description: Stockpile Ore (No Palo Verde Ore Milled) Year: 1984
Description: Twin Buttes Mine Closed In 1984 Year: 1983
Description: Inc. 15,831 Mt Cu Rec From Palo Verde Year: 1983
Description: Inc. 149 Mt Mo From Palo Verde Ore Year: 1983
Description: Cathode Cu Produced At Oxide Plant Year: 1983
Description: No Oxide Ore Mined No Year: 1983
Description: Includes 2,836,000 Mt From Palo Verde Year: 1983
Description: Ore Mined At Twin Buttes Year: 1982
Description: Inc. 324 Mt Mo From Palo Verde Ore Year: 1982
Description: Produced From Oxide Plant Year: 1982
Description: Inc. 24,691 Mt Cu From Palo Verde Ore Year: 1982
Description: Cu Oxide Ore Mined At Twin Buttes Year: 1982
Description: Inc. 4,248,000 Mt Palo Verde Ore Year: 1982
Description: Ore Mine At Twin Buttes Year: 1981
Description: Inc 252 Mt Mo From Palo Verde Ore Year: 1981
Description: Produced At Oxide Plant Year: 1981
Description: Inc. 29,174 Mt Cu From Palo Verde Ore Year: 1981
Description: Cu Oxide Ore Mined At Twin Buttes Year: 1981
Description: Ore Milled At Twin Buttes (Includes Year: 1981
Description: Ore Mined At Twin Buttes Year: 1980
Description: Cu Cathode-Oxide Mill 63719000 Year: 1980
Description: Sulfide Ore Treated Incl Palo Verde Feed Year: 1979
Description: Cu Cathode-Oxide Mill 70343000 Year: 1978
Description: Sulfide Ore Treated 6795600 Year: 1978
Description: Cu Cathode-Oxide Mill 71614000 Year: 1979
Description: Sulfide Ore Treated Incl Palo Verde Feed Year: 1977
Description: Cu Cathode-Oxide Mill 68772000 Year: 1977
Description: Sulfide Ore Treated 8387800 Year: 1976
Description: Us Bumines Stats - Smelter Cu Output Year: 1976
Description: Pounds Cu Cathode/Twin Buttes Oxide Mill Year: 1974
Description: Us Bumine Stats - Smelter Cu Output Year: 1975
Description: Us Bumines Stats - Smelter Cu Output Year: 1971
Description: Us Bumines Stats - Smelter Cu Output Year: 1972
Time Period: 1969-1972
Material type: Ore
Year: 1972
Description: Us Bumines Stats - Smelter Cu Output Year: 1973
Description: Us Bumines Stats - Smelter Cu Output Year: 1971
Material type: Ore
Year: 1970
Description: Us Burmines Stats - Smelter Cu Output Year: 1970
Material type: Ore
Year: 1969
Description: Us Bumines Stats - Smelter Cu Output Year: 1929
Material type: Ore
Mt Ore Mined
Mt Ore Mined
>392 tonnes U3O8
Mt Ore Mined
Mt Ore Mined
Mt Ore Mined
Mine & Mills Closed 9/85
8949 Mtpy Cu (Cathode)
1355000 Mtpy Oxide Ore Milled
No Mo Recovered
No Cathode Cu Produced
22788 Mtpy Cu Recovered
3137000 Mtpy Ore Milled
No Ore Mine At T B Or P V
21576 Mtpy Cu Recovered
270 Mtpy Mo Produced
22973 Mtpy Cu (Cathode)
Oxide Ore Mined
6815000 Mtpy Ore Milled
661000 Mtpy Ore Mined
1876 Mtpy Mo Produced
25577 Mtpy Cu Cathode Produced
104228 Mtpy Cu Recovered
3338000 Mtpy Cu Oxide Ore Mined
14789000 Mtpy Ore Milled
10540000 Mtpy Ore Mined
1004 Mtpy Mo Produced
30809 Mtpy Cu (Cathode)
91914 Mtpy Cu Recovered
3342000 Mtpy Cu Oxide Ore Mined
14513000 Mtpy Ore Milled
9926000 Mtpy Ore Mined
Pounds Of Cathode Copper
4419699 Short Tons
Pounds Of Cathode Copper
Short Tons
Pounds Of Cathode Copper
13911000 Short Tons
Pounds Of Cathode Copper
Short Tons
128247000 Pounds Of Cu From Smelter
57925000 Lbs Of Cathode Cu From Ox
88644000 Pounds Of Cu From Smelter
16617000 Pounds Of Cu From Smelter
104208000 Pounds Of Cu From Smelter
154446000 Pounds Of Cu From Smelter
124451000 Pounds Of Cu From Smelter
172061000 Pounds Of Cu From Smelter
21812000 Pounds Of Cu From Smelter

Deposit

Record Type: Deposit
Operation Category: Past Producer
Deposit Type: Porphyry Cu, Skarn Related
Operation Type: Surface
Mining Method: Open Pit
Milling Method: Flotation
Year First Production: 1969
Year Last Production: 1994
Discovery Year: 1870
Years of Production:
Organization:
Significant: Y
Deposit Size: L

Physiography

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

Mineral Deposit Model

Model Name: Porphyry Cu, skarn-related

Orebody

Form: Irregular

Structure

Type: L
Structure: NW Trending Fault Just North of Mine

Type: L
Structure: Stratigraphic Unconformities

Type: L
Structure: Sediments Folded & Contorted, Dip Steeply, Several Fault Systems

Alterations

Alteration Type: L
Alteration: Biotization, Sericitization

Alteration Type: L
Alteration: 200 Ft Thick Oxide Zone, Skarn, Recrystallization

Rocks

Name: Limestone
Role: Host
Age Type: Host Rock
Age Young: Late Permian

Name: Granite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cretaceous

Analytical Data

Analytical Data: Sulfide Zone Averages 0.5% Cu. Diorite Porphyry Contains 0.4-0.6% Cu in Places.

Materials

Ore: Chalcopyrite
Ore: Bornite
Ore: Brochantite
Ore: Chalcocite
Ore: Chrysocolla
Ore: Cuprite
Ore: Galena
Ore: Malachite
Ore: Melaconite
Ore: Molybdenite
Ore: Wulfenite
Ore: Wollastonite
Ore: Tenorite
Ore: Sphalerite
Ore: Pyrite
Ore: Powellite
Gangue: Anhydrite
Gangue: Antigorite
Gangue: Biotite
Gangue: Calcite
Gangue: Epidote
Gangue: Fluorite
Gangue: Quartz
Gangue: Sericite
Gangue: Talc
Gangue: Actinolite
Unknown: Magnetite

Comments

Comment (Ownership): Park Corp. Bought The Twin Buttes Equipment And Facilities In 1986 For Resale. The Firm Also Plans To Acquire The Property For Future Devel. Not Related To Mining. Cyprus Bought Twin Buttes As Supplemental Feed For Sierrita Mill

Comment (Deposit): Original Evaluation Was Done In 1978. Revised In 1980. Updated In 1983, In July 1987, And In 1991.

Comment (Production): Production Data For Years 1981 - 1985 From Primary Copper Industry Of Arizona Special Reports For 1981 - 1985 (Special Repts Nos 5,6,8,9 & 10.) Az Dept Of Mines & Min. Resources. Mine & Sulfide And Oxide Plants Closed In Sept. 1985. All Mine & Mill Equipment Sold. Twin Buttes Mine Closed In June 1994 - Ore Mined Out.

Comment (Deposit): Associated Minerals: actinolite, anhydrite/gypsum, apatite, apophyllite, azurite/malachite, biotite, bornite, brochantite, chalcocite/digenite, chalcopyrite, chlorite, chrysocolla, copper, cuprite/tenorite, Cu-Mn wad, diopside, epidote, ferrimolybdite, fluorite, galena, garnet, goethite/limonite, hematite/specularite, jarosite, magnetite, molybdenite, montmorillonite, powellite, pyrite, pyrolusite, pyrrhotite, rhodochrosite, rhodonite, rutile, scheelite, sericite, siderite, sphalerite, stibnite, tenorite, tetrahedrite, vanadinite, vesuvianite, wollastonite, wulfenite

Comment (Deposit): Associated Rocks: breccia, quartz monzonite porphyry, quartz-feldspar porphyry, skarn, andesite, anhydrite, conglomerate, dolomite, fanglomerate, granite, limestone, quartzite, rhyodacite porphyry, rhyolite, sandstone, shale, siltstone, tuff

Comment (Commodity): Total Sulfide Content Generally Corresponds To Total Copper Content.

Comment (Deposit): STRONGEST MINERALIZATION FOUND IN SILICATED, GARNETIZED, CHLORITIZED LIMESTONE & SILTSTONE; QUARTZITE ONLY WEAKLY MINERALIZED. CLASTICS ARE MINERALIZED ON S, AND BETTER CU VALUES OCCUR IN CONTACT WITH PORPHYRY TO THE SE. PORPHYRY SHOWS ONLY SCATTERED AND WEAK MINERALIZATION. SULFIDE ZONE 600-800 FT BELOW SURFACE. WOLLASTONITE OCCURS IN SKARN.

Comment (Deposit): Other Slightly Mineralized Garnetiferous Zones Eastward Along The Limestone - Granite Fault Contact.

References

Reference (Geology): Einaudi, M.T., 1982, Description of skarns associated with porphyry copper plutons, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 139-183.

Reference (Geology): Kelley, J.L., 1976, Geology of the Twin Buttes copper deposit, Pima county, Arizona: AIME Annual Meeting, February 22?26, 1976, Las Vegas, Preprint No. 76?1?3, 23 p.

Reference (Geology): Titley, S.R., 1982, Some features of tectonic history and ore genesis in the Pima mining district, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 387?406.

Reference (Production): Sutulov, Alexander, Copper Porphyries, Univ. Of Utah Printing Services, 1974. (Mill)

Reference (Geology): Barter, C. F., 1978, Stratigraphy, alteration, and ore controls in the main ore zone, Twin Buttes mine, Pima County, Arizona: Arizona Geological Society Digest, v. 11, p. 115?116.

Reference (Geology): Barter, C.F., and Kelly, J.L., 1982, Geology of the Twin Buttes mineral deposit, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 407?432.

Reference (Deposit): Singer and others, 2008

Reference (Reserve-Resource): Cyprus/Amax 1972-92 SEC Form 10K; Anaconda 1971-75 SEC Form 10K; PCIA 1975-93

Reference (Production): Emj 7/77 (Countercurrent Decantation-Oxide Plant)

Reference (Deposit): Peirce, H.W., 1990, Arizona Geological Survey Industrial Mineral Card Files.

Reference (Deposit): Skillings Mining Review 6/4/77,P.12-16, Anamax Mining Co.'S Copper Operations At Twin Buttes Mine (Oxide Plant, Mining Equipment, Exploration)

Reference (Deposit): Mining Magazine. July 1991. Moly And More From Sierrita.

Reference (Deposit): Hopkins,W.R., and Lynch,A.J., Anamax Oxide Plant: A New U.S. Dimension. E/Mj, 2/77, P.56.

Reference (Deposit): Cyprus Minerals Company Annual Report 1988 P. 2.

Reference (Production): World Mining, 11/76, P. 77.

Reference (Deposit): World Mining 5/77, P.96-99 (Reserves, Mining Rate, Recovery Production Stats.)

Reference (Deposit): Isolated Processing Of Twin Buttes Ore In The Cyprus Sierrita Mill. Aime Annual Meeting. Arizona Section. December 5, 1989.

Reference (Deposit): Cooper, J. R., Some Geologic Features Of The Pima Mining District, Pima County, Arizona: USGS Bulletin 1112 - C.

Reference (Deposit): Brooke, James N. Uranium Recovery From Copper Leaching Operations In Mining Congress Journal, 8/77, P. 38-41.

Reference (Deposit): Skillings Mining Review, 5/24/80, P. 7.

Reference (Deposit): Keith, S. B., 1974 , Index Of Mining Properties In Pima County, Arizona: Arizona Bureau Of Mines Bulletin, 189 , P. 133 .

Reference (Deposit): Energy Use Patterns In Metalurgical And Nonmetallic Mineral Processing: U.S. Dept. Of Commerce P.B. 245-759.

Reference (Deposit): Pay Dirt 4/25/77, P.57 (Drying Concentrate, Exploration)

Reference (Deposit): Lorraine, 1976, USBM Ic 8702

Reference (Deposit): Cummings, J. B., And Romslo, T. M., 1950 , Investigation Of The Twin Buttes Copper Mines, Pima Co, Ariz: USBM R. I. 4732 .

Reference (Other Database): Cimri

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