Sierrita

Site Name

Primary: Sierrita
Secondary: Duval Sierrita Corp.
Secondary: Twin Buttes

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Commodity

Primary: Copper
Secondary: Silver
Secondary: Zinc
Secondary: Lead
Secondary: Molybdenum
Secondary: Gold
Tertiary: Rhenium

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Location

State: Arizona
County: Pima
District: Pima

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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

Type: Fee Ownership
Type: Patented
Type: Located Claim

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Workings

Type: Surface

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Ownership

Owner Name: FREEPORT-MCMORAN COPPER AND GOLD INC
Percent: 100.0
Home Office: One North Central Avenue Phoenix AZ 85004 United States
Info Year: 2009

Owner Name: PARK CORP
Home Office: P. O. Box 1488 Green Valley AZ 85622 United States
Info Year: 2009

Owner Name: PHELPS DODGE CORP (FREEPORT-MCMORAN COPPER A
Percent: 100.0
Info Year: 2009

Owner Name: Cyprus Amax Minerals Co.
Company ID: 200144
Percent: 100.0
Home Office: Colorado
Info Year: 1995
Years: 1990 - 1999

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Production

Year: 2009
Material type: The Mo production amount includes Morenci, Bagdad, and others. Freeport-McMoRan 2009 10-K p. 9, 23.
Year: 2008
Material type: The Mo production amount includes Morenci, Bagdad, and others. Freeport-McMoRan 2008 10-K p. 8, 21.
Year: 2007
Material type: Freeport-McMoRan 2009 10-K, p. 23.
Year: 2006
Mined: 40326000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2006 10-K, p. 13-14.
Year: 2005
Mined: 37274000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2006 10-K, p. 13-14.
Year: 2004
Mined: 32854000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2006 10-K, p. 13-14.
Year: 2003
Mined: 24520000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2006 10-K, p. 13-14.
Year: 2000
Mined: 51442000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2001 10-K p. 6-7.
Year: 2001
Mined: 47609000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2001 10-K p. 6-7.
Year: 2002
Mined: 19603000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2006 10-K, p. 13-14.
Year: 1999
Mined: 11206000.000 mt
Material type: Mill ore processed + leach ore placed in stockpiles. Phelps Dodge 2001 10-K p. 6-7.
Year: 1998
Mined: 54000000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution was probably very small to insignificant. Cyprus Amax 1998 10-K p. 4.
Year: 1997
Mined: 52000000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution probably very small to insignificant. Cyprus Amax 1997 10-K p. 4.
Year: 1996
Mined: 47000000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution probably very small to insignificant. Cyprus Amax 1997 10-K p. 4.
Year: 1993
Mined: 32600000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution was significant. Cyprus Amax 1993 10-K p. 7-9.
Year: 1994
Mined: 42000000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution was small. Cyprus Amax 1994 10-K p. 3-4.
Year: 1995
Mined: 48000000.000 mt
Material type: Sierrita/Twin Buttes. TB contribution was very small. Cyprus Amax 1995 10-K p. 3-4.
Year: 1992
Mined: 31900000.000 mt
Material type: Sierrita/Twin Buttes. 6.8 mi conveyor system from TB to Sierrita probably made a significant contribution. Cyprus Amax 1993 10-K p. 7-9.
Year: 1984
Description: 78,985 Mt Cu & 7,653 Mt Mo Produced 27020000 Mtpy Ore
Year: 1985
Description: 102,290 Mt Cu & 8,850 Mt Mo Produced 37000000 Mtpy Ore
Year: 1986
Description: 73,945 Mt Cu & 7,088 Mt Mo Produced 26928000 Mtpy Ore
Year: 1983
Description: 59,149 Mt Cu & 5,731 Mt Mo Produced 18804000 Mtpy Ore
Year: 1982
Description: 47,417 Mt Cu & 4,388 Mt Mo Produced 16142000 Mtpy Ore
Year: 1981
Description: Average Grade 0.302% Cu; Recovery 86.7% 29587000 Metric Tons Of Ore Milled
Year: 1979
Description: Average Grade 0.338% Cu; Recovery 87.7% 30312000 Metric Tons Of Ore Milled
Year: 1980
Description: Average Grade 0.337% Cu; Recovery 88.7% 30714000 Metric Tons Of Ore Milled
Year: 1977
Description: 26975000 Metric Tons Of Ore Milled
Year: 1978
Description: Average Grade 0.338% Cu; Recovery 87.1% 30441000 Metric Tons Of Ore Milled

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Deposit

Record Type: Deposit
Operation Category: Producer
Deposit Type: Porphyry Cu-Mo
Operation Type: Surface
Mining Method: Open Pit
Milling Method: Flotation
Year First Production: 1970
Discovery Year: 1960
Years of Production:
Organization:
Significant: Y
Deposit Size: L

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Physiography

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

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Mineral Deposit Model

Model Name: Porphyry Cu-Mo

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Orebody

Form: V-shaped

Not available

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Structure

Type: L
Structure: Fractures that strike N50-85E and N50-25W that are steeply dipping.

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Alterations

Alteration Type: L
Alteration: Potassic, Phyllic, Argillic, Supergene Effects, Propylitic

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Rocks

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock
Age in Years: 58.700000+-
Age Young: Tertiary
Age Old: Cretaceous

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Analytical Data

Not available

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Materials

Ore: Galena
Ore: Molybdenite
Ore: Chalcocite
Ore: Bornite
Ore: Chrysocolla
Ore: Cuprite
Ore: Magnetite
Ore: Malachite
Ore: Marcasite
Ore: Pyrite
Ore: Sphalerite
Ore: Tenorite
Ore: Tennantite
Ore: Chalcopyrite
Gangue: Fluorite
Unknown: Gold
Unknown: Silver

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Comments

Comment (Workings): Open Pit, Mine Area Approximated From Map

Comment (Production): Pre-Mine Stripping Began In 1968 With Initial Production In 1970. In 1980 Produced 90,000 Tons Ore And 135,000 Tons Waste Daily.

Comment (Location): Is Part Of Esperanza-Sierrita Deposit. WHEN CYPRUS PURCHASED THE SIERRITA-ESPERANZA MINE & MILL COMPLEX THEY COMBINED THE TWO PROPERTIES AS ONE COMPLEX CALLED SIERRITA. THE RESERVES HAVE BEEN COMBINED AND THE ESPERANZA PIT IS NOW CALLED THE EAST PIT AND THE SIERRITA PIT IS CALLED THE WEST PIT.

Comment (Production): Approx. 4.7 Mt/Dy, 13.5%, Of Pb Goes To The Ferromolybdenum Plant; The Remainder Is Sold As Molybdic Trioxide.

Comment (Development): Owned By Duval Corp. Until 1986. Part Of The Deposit Is Mined By Solution.

Comment (Production): Processing method: Crushing, Grinding, Flotation, Solvent-Extraction Electrowinning

Comment (Identification): Data Merged from Sierrita Mine Deposit ID 10039631 **** SEE Esperanza Deposit ID 10039594 for related record.

Comment (Orebody): Ore genesis: Contact Metamorphic (Metasomatic), Hydrothermal

Comment (Orebody): Orebody type: Replacement, Disseminated

Comment (Ownership): Property Sold To Cyprus Minerals By Pennzoil In Mar 1986 For An Undisclosed Amount. Cyprus Minerals And Amax Merged In November 1993. Corporate Headquarters Address: Cyprus Amax Minerals Co. 9100 East Mineral Circle Englewood, Co 80112 Division Address: Cyprus Climax Metals Co. 1501 W. Fountainhead Parkway Suite 290 Tempe, Az 85282 Mine / Operating Co. Address: Cyprus-Sierrita Corp. P.O. Box 527 Green Valley, Az 85622

Comment (Production): Reserves & Grades Are As Of 12/31/94 And Includes The Sierrita And Twin Butte Pits. Twin Buttes Pit Will Be Mined Out Mid-1994. 1982-1985 Production Data From Primary Copper Industry Of Az Special Reports 1982-1985. Az Dept Of Mines & Mineral Res. 1986 Production Provided By Pennzoil Corp And Cyprus Minerals Co.

Comment (Economic Factors): Reserves & Grades Are As Of 12/31/94 And Includes The Sierrita And Twin Butte Pits. Twin Buttes Pit Will Be Mined Out Mid-1994. 1982-1985 Production Data From Primary Copper Industry Of Az Special Reports 1982-1985. Az Dept Of Mines & Mineral Res. 1986 Production Provided By Pennzoil Corp And Cyprus Minerals Co. Johnson Camp Sx-Ew Lix Plant Relocated To Sierrita/Esperanza Mine For Cost Of $2.4mm (1987). Cyprus Stated That A $ 40 Million Non-Recourse Loan Was Used To Purchase Sierrita.

Comment (Deposit): The Property Was Visited By Rc Smith And A Hite On 1-12-78. A Copy Of The Patent Application For The Clear Process Is Located With The Property File. Property Updated Jul 1987. Property Visited April 8, 1988. Complete Update Done In August 1988.

Comment (Reserve-Resource): Reserves & Grades Are As Of 12/31/94 And Includes The Sierrita And Twin Butte Pits. Twin Buttes Pit Will Be Mined Out Mid-1994.

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References

Reference (Geology): Ruiz, J. and Mathur, R., 1999, Metallogenesis in continental margins: Re-Os evidence from porphyry copper deposits in Chile; in Lambert, D.D. and Ruiz, J., eds., Application of Radiogenic Isotopes to Ore Deposit Research and Exploration, Reviews in Economic Geology, v. 12, p. 59-72.

Reference (Deposit): E and M J 8/70 (Mill Rcvry).

Reference (Geology): Barter, Charles F. And James L. Kelly, Geology Of The Twin Buttes Mineral Deposit, In Advances In Geology Of The Porphyry Copper Deposits- Southwestern North America, 1982, University Of Arizona Press, P.407-432.

Reference (Deposit): Co Prospectus 1970 (Tons and Grade- Cu and Mo).

Reference (Reserve-Resource): Securities and Exchange Commission Form 10k For Pennzoil Company For Year Ending Dec. 31, 1981.

Reference (Production): Nickel News. Issue 32/52. 8/6/97. P.12.

Reference (Deposit): O'Neil, Thomas J., Cyprus Sierrita Explains Effort To Control Tailings Dust, Southwestern Pay Dirt, 10/90, P.10a,11a.

Reference (Deposit): Southwestern Pay Dirt. November 1986, P. 10a-11a.

Reference (Deposit): Southwestern Pay Dirt. August 1987, P. 18a-19a.

Reference (Geology): Titley, Spencer R., Some Features Of Tectonic History And Ore Genesis In The Pima Mining District, In Advances In Geology Of The Porphyry Copper Deposits- Southwestern North America, 1992, University Of Arizona Press, P.387-406.

Reference (Deposit): Dillard, Gary, Benefits Starting From $350 Million Program, Southwestern Pay Dirt, 9/93, P.4a,5a.

Reference (Deposit): Dillard, Gary, Cyprus Cuts 220 At Sierrita In Fight To Reduce Unit Costs, Southwestern Pay Dirt, 8/93, P.12a.

Reference (Deposit): Mining Magazine, 7/91, P.5.

Reference (Deposit): Epler, Bill, Cyprus Sierrita Gets Lower Power Rate From Tucson Electric, Southwestern Pay Dirt, 4/91, P.24a.

Reference (Deposit): Epler, Bill, Power Rates Lead Cyprus Sierrita To Consider Its Own Plant, Southwestern Pay Dirt, 1/91, P.7a.

Reference (Deposit): Southwestern Pay Dirt, 1/91, P.12a.

Reference (Deposit): Cyprus Amax Minerals Co., News Release, 12/31/93, 1pp.

Reference (Deposit): Hill, Leonard N., Installing Cyclones On The Primary Grinding Circuit At Cyprus Sierrita, Mining Engineering, 9/94, P.1057-1060.

Reference (Reserve-Resource): Cyprus Minerals Company 1987 Form 10-K Report, Page 3.

Reference (Reserve-Resource): Cyprus Amax Minerals Co., 1994 Form 10-K, P.2.

Reference (Reserve-Resource): Cyprus-Amax Minerals Co., Sec Form 10-K Rept, 12/31/93, P.7.

Reference (Deposit): Southwestern Pay Dirt. July 1986, P. 18a-19a.

Reference (Reserve-Resource): Cyprus Amax Minerals Company 1995 10-K, P.2-4.

Reference (Deposit): Southwestern Pay Dirt. April 1986, P. 8a-10a.

Reference (Deposit): Southwestern Pay Dirt. March 1986, P. 4a-5a.

Reference (Deposit): Rocky Mountain Pay Dirt. April 1986, P. 22a.

Reference (Geology): West, Richard J. And Daniel M. Aiken, Geology Of The Sierrita- Esperanza Deposit, In Advances In Geology Of The 1982, University Of Arizona Press, P.433-465.

Reference (Deposit): Cyprus Minerals Company. Press Release, Feb. 18, 1986.

Reference (Deposit): Cyprus Minerals Company. 1987 Annual Report

Reference (Deposit): Cyprus Minerals Company. 1986 Form 10-K Report, P.1, 3-7.

Reference (Deposit): Arizona Pay Dirt. Pennzoil Pushing Duval Asset Sale. December 1984, Pp. 8a-9a.

Reference (Deposit): Emj August 70 Pg 70 Flot Mill-Feed Cap 85000 T

Reference (Deposit): Emj June 75 Pg 98 (Good) Emj Mine Directory 1975 (Good)

Reference (Deposit): Engineering And Mining Journal, October, 1987, P. 12.

Reference (Geology): The Porter GeoConsultancy webpage for Sierrita - Esperanza contains a description of the geology. Accessed on 8/26/2010. http://www.portergeo.com.au/
URL: http://www.portergeo.com.au

Reference (Geology): Jensen, P.W., 1998, A structural and geochemical study of the Sierrita porphyry copper system, Pima County, Arizona; unpublished M.S. thesis, University of Arizona, Tucson, 136 p.

Reference (Deposit): Greeley, 1978, Admr Spec Rept No 2.

Reference (Deposit): Lynch, 1966, In Titley and Hicks, Univ Of Az Press.

Reference (Deposit): Keith, 1974, Abm Bull 189, P. 138.

Reference (Reserve-Resource): Greeley, 1978; Sawyer And Others, 1992.

Reference (Other Database): Cimri

Reference (Production): Aiken and West, 1978; Sawyer And Others, 1992.

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: U.S. Bureau Of Mines Special Publication, 334 P.

Reference (Deposit): Aiken and West, 1978, Az Geol Soc Digest Vii, P. 117-128.

Reference (Geology): McCandless, T.E. and Ruiz, J., 1993, Rhenium-osmium evidence for regional mineralization in southwestern North America; Science, v. 261, p. 1282-1286.

Reference (Geology): Porter, T.M., 1998, An overview of the World's porphyry and other hydrothermal copper & gold deposits and their distribution; in Porter, T. M., ed., Porphyry and Hydrothermal Copper and Gold Deposits: a global perspective, PACRIM '98 Conference Proceedings, Australian Mineral Foundation, p. 3-17.

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