1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Sierrita

Producer in Pima county in Arizona, United States with commodities Copper, Molybdenum, Gold, Silver, Lead, Zinc, Rhenium
Map
XML
JSON
KML
A
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Alteration
  9. Mineral occurrence model information
  10. Host and associated rocks
  11. Nearby scientific data
  12. Geologic structures
  13. Ore body information
  14. Controls for ore emplacement
  15. Economic information about the deposit and operations
  16. Mining district
  17. Mineral rights holdings
  18. Land status
  19. Ownership information
  20. Production statistics
  21. Reserves and resources
  22. Workings at the site
  23. Links to other databases
  24. Bibliographic references
  25. General comments
  26. Reporter information

Geologic information

Identification information

Deposit ID 10137918
MRDS ID M050531
MAS/MILS ID 0040190004
Record type Deposit
Current site name Sierrita
Alternate or previous names Duval Sierrita Corp., Twin Buttes

Comments on the site identification

  • Data Merged from Sierrita Mine Deposit ID 10039631
    **** SEE Esperanza Deposit ID 10039594 for related record.

Geographic coordinates

Point of reference Ore Body
Geographic coordinates: -111.14879, 31.87152 (WGS84)
Elevation 1250
Location accuracy 500(meters)

Site location context

Political divisions (FIPS codes)

Pima(county)

Arizona(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Batamote Hills(quadrangle 1:24,000 scale)

Sells(quadrangle 1:100,000 scale)

Nogales(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Santa Cruz(hydrologic unit)

Santa Cruz(hydrologic accounting unit)

Middle Gila(hydrologic subregion)

Lower Colorado(hydrologic region)

Geographic areas

Country State County
United States Arizona Pima

Public Land Survey System information

Meridian Township Range Section Fraction State
Gila and Salt River 018 S 012 E 07,08,17,18 SW Arizona

Comments on the location information

  • 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.

Commodities

Commodity Importance
Copper Primary
Molybdenum Secondary
Gold Secondary
Silver Secondary
Lead Secondary
Zinc Critical Secondary
Rhenium Tertiary

Materials information

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

Alteration

  • (Local) Potassic, Phyllic, Argillic, Supergene Effects, Propylitic

Mineral occurrence model information

Model code 79
USGS model code 21a
Deposit model name Porphyry Cu-Mo
Mark3 model number 2

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Quartz Monzonite
    Rock unit name Ruby Star Quartz Monzonite Porphyry;Harris Ranch Quartz Monzonite
    Stratigraphic age (youngest) Tertiary
    Stratigraphic age (oldest) Cretaceous
    Chronological age 58.7
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Quartz Latite

Nearby scientific data

Ore Body (1) -111.14879, 31.87152
ListMap

Economic information

Geologic structures

Type of structure Local
Structure name Fractures that strike N50-85E and N50-25W that are steeply dipping.

Ore body information

  • Thickness 500M
    Length 2300M
    Width 1800M
    Depth to top 53M
    Field Value
    MAS Matrix # 1
    MAS Column # 1
    Type of Orebody #1 DISSEMINATED
    Shape of Orebody #1 MASSIVE
    Primary mode of Origin OXIDATION
    Primary Ore Control FAULTING
    Secondary Ore Control IGNEOUS
    Degree of Wallrock Alter. INTENSE
    Type of Wallrock Alter. #1 POTASSIC
    Type of Wallrock Alter. #2 PYRITIZATION
    Minimum Depth to Top 40
    Date of Last Modification 880826
  • Area 1800HA
    Field Value
    Total Surface Area (HA) 1800
    Date of Last Modification 910418
  • General form V-shaped
    Strike N50-85E,N50-25W

Comments on the ore body information

  • Ore genesis: Contact Metamorphic (Metasomatic), Hydrothermal
  • Orebody type: Replacement, Disseminated

Controls for ore emplacement

  • N50-85E & N50-25W Fractures. Seams & Fractures, Breccia Pipe

Economic information about the deposit and operations

Operation type Surface
Development status Producer
Commodity type Metallic
Deposit size Large
Significant Yes
Discovery year 1960
Mining method Open Pit
Year of first production 1970
Milling method Flotation

Mining district

District name Pima

Mineral rights holdings

Type of mineral rights Located Claim
Type of mineral rights Patented
Type of mineral rights Fee Ownership

Land status

Ownership category Private

Ownership information

  • Type Lessee/Operator
    Owner Cyprus Amax Minerals Co.
    ID 0200144
    Interest 100
    Home office Colorado
    Year 1995
    First year 1990
    Last year 1999
  • Type Lessee/Operator
    Owner PHELPS DODGE CORP (FREEPORT-MCMORAN COPPER A
    Interest 100
    Year 2009
    Last year 2006
  • Type Lessor
    Owner PARK CORP
    Home office P. O. Box 1488\nGreen Valley AZ 85622\nUnited States
    Year 2009
  • Type Lessee/Operator
    Owner FREEPORT-MCMORAN COPPER AND GOLD INC
    Interest 100
    Home office One North Central Avenue\nPhoenix AZ 85004 \nUnited States
    Year 2009

Comments on the ownership information

  • 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

Production statistics

  • 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
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 87wt-pct
  • Year 1979
    Description Average Grade 0.338% Cu; Recovery 87.7% 30312000 Metric Tons Of Ore Milled
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 88wt-pct
  • Year 1980
    Description Average Grade 0.337% Cu; Recovery 88.7% 30714000 Metric Tons Of Ore Milled
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 89wt-pct
  • Year 1981
    Description Average Grade 0.302% Cu; Recovery 86.7% 29587000 Metric Tons Of Ore Milled
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 87wt-pct
  • Year 1982
    Description 47,417 Mt Cu & 4,388 Mt Mo Produced 16142000 Mtpy Ore
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 47417mt
    Major Molybdenum Molybdenum 4388mt
  • Year 1983
    Description 59,149 Mt Cu & 5,731 Mt Mo Produced 18804000 Mtpy Ore
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 59149mt
    Major Molybdenum Molybdenum 5731mt
  • Year 1984
    Description 78,985 Mt Cu & 7,653 Mt Mo Produced 27020000 Mtpy Ore
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 78985mt
    Major Molybdenum Molybdenum 7653mt
  • Year 1985
    Description 102,290 Mt Cu & 8,850 Mt Mo Produced 37000000 Mtpy Ore
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 102290mt
    Major Molybdenum Molybdenum 8850mt
  • Year 1986
    Description 73,945 Mt Cu & 7,088 Mt Mo Produced 26928000 Mtpy Ore
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 73945mt
    Major Molybdenum Molybdenum 7088mt
  • Year 1992
    Material Sierrita/Twin Buttes. 6.8 mi conveyor system from TB to Sierrita probably made a significant contribution. \nCyprus Amax 1993 10-K p. 7-9.
    Ore mined 31900000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary Copper Copper 130900mt 0wt-pct
    Secondary Molybdenum Molybdenum 6990mt 0wt-pct
  • Year 1993
    Material Sierrita/Twin Buttes. TB contribution was significant.\nCyprus Amax 1993 10-K p. 7-9.
    Ore mined 32600000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Molybdenum Molybdenum 8210mt 0wt-pct
    Primary Copper Copper 119800mt 0wt-pct
  • Year 1994
    Material Sierrita/Twin Buttes. TB contribution was small. \nCyprus Amax 1994 10-K p. 3-4.
    Ore mined 42000000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Molybdenum Molybdenum 10000mt
    Primary Copper Copper 115000mt
  • Year 1995
    Material Sierrita/Twin Buttes. TB contribution was very small. \nCyprus Amax 1995 10-K p. 3-4.
    Ore mined 48000000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Mo Molybdenum Molybdenum 11000mt
    Primary Cu Copper Copper 109000mt
  • Year 1996
    Material Sierrita/Twin Buttes. TB contribution probably very small to insignificant.\nCyprus Amax 1997 10-K p. 4.
    Ore mined 47000000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Mo Molybdenum Molybdenum 8600mt
    Primary Cu Copper Copper 105000mt
  • Year 1997
    Material Sierrita/Twin Buttes. TB contribution probably very small to insignificant. \nCyprus Amax 1997 10-K p. 4.
    Ore mined 52000000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Mo Molybdenum Molybdenum 9100mt
    Primary Cu Copper Copper 112000mt
  • Year 1998
    Material Sierrita/Twin Buttes. TB contribution was probably very small to insignificant. \nCyprus Amax 1998 10-K p. 4.
    Ore mined 54000000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary Molybdenum Molybdenum 10000mt
    Primary Copper Copper 103000mt
  • Year 1999
    Material Mill ore processed + leach ore placed in stockpiles.\nPhelps Dodge 2001 10-K p. 6-7.
    Ore mined 11206000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 23100mt
  • Year 2000
    Material Mill ore processed + leach ore placed in stockpiles.\nPhelps Dodge 2001 10-K p. 6-7.
    Ore mined 51442000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 111000mt
  • Year 2001
    Material Mill ore processed + leach ore placed in stockpiles.\nPhelps Dodge 2001 10-K p. 6-7.
    Ore mined 47609000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 109700mt
  • Year 2002
    Material Mill ore processed + leach ore placed in stockpiles. \nPhelps Dodge 2006 10-K, p. 13-14.
    Ore mined 19603000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 69129mt
  • Year 2003
    Material Mill ore processed + leach ore placed in stockpiles. \nPhelps Dodge 2006 10-K, p. 13-14.
    Ore mined 24520000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 68600mt
  • Year 2004
    Material Mill ore processed + leach ore placed in stockpiles. \nPhelps Dodge 2006 10-K, p. 13-14.
    Ore mined 32854000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 70300mt
  • Year 2005
    Material Mill ore processed + leach ore placed in stockpiles. \nPhelps Dodge 2006 10-K, p. 13-14.
    Ore mined 37274000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 71900mt
  • Year 2006
    Material Mill ore processed + leach ore placed in stockpiles. \nPhelps Dodge 2006 10-K, p. 13-14.
    Ore mined 40326000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary in conc & EW Copper Copper 73300mt
  • Year 2007
    Material Freeport-McMoRan 2009 10-K, p. 23.
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Primary recoverable Copper Copper 68000mt
  • Year 2008
    Material The Mo production amount includes Morenci, Bagdad, and others. \nFreeport-McMoRan 2008 10-K p. 8, 21.
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary recoverable Molybdenum Molybdenum 9100mt
    Primary recoverable Copper Copper 85300mt
  • Year 2009
    Material The Mo production amount includes Morenci, Bagdad, and others. \nFreeport-McMoRan 2009 10-K p. 9, 23.
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Secondary recoverable Molybdenum Molybdenum 8600mt
    Primary recoverable Copper Copper 77100mt

Comments on the production information

  • 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.
  • Approx. 4.7 Mt/Dy, 13.5%, Of Pb Goes To The Ferromolybdenum Plant; The Remainder Is Sold As Molybdic Trioxide.
  • Pre-Mine Stripping Began In 1968 With Initial Production In 1970. In 1980 Produced 90,000 Tons Ore And 135,000 Tons Waste Daily.
  • Processing method: Crushing, Grinding, Flotation, Solvent-Extraction Electrowinning

Reserves and resources

  • Type In-situ
    Estimate year 2008
    Total endowment 2262000000mt ore
    Remarks Esperanza-Sierrita deposit total endowment. 6.65 million mt contained Cu metal.\nSinger 2008 in PorCuEX2008.xls.
    Commodity Subtype Grade units Group Importance Year
    Copper 0.294 wt-pct Copper Primary 2008
    Molybdenum 0.0292 wt-pct Molybdenum Secondary 2008
    Gold 0.003 g/mt Gold Secondary 2008
    Silver 1.2 g/mt Silver Secondary 2008
  • Type In-situ
    Estimate year 1994
    Measured 849000000mt ore
    Demonstrated 849000000mt ore
    Total resources 849000000mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.29 wt-pct Copper Major 1994
    Molybdenum Mo 0.032 wt-pct Molybdenum Major 1994
  • Type In-situ
    Estimate year 1996
    Measured 855000000mt ore
    Demonstrated 855000000mt ore
    Total resources 855000000mt ore
    Commodity Subtype Grade units Group Importance Year
    Molybdenum Mo 0.03 wt-pct Molybdenum Major 1996
    Copper Cu 0.27 wt-pct Copper Major 1996
  • Type In-situ
    Estimate year 1971
    Total resources 291609000mt ore
    Commodity Subtype Grade units Group Importance Year
    Molybdenum Mo 0.003 wt-pct Molybdenum Secondary 1971
    Copper Cu 0.32 wt-pct Copper Primary 1971
  • Type In-situ
    Estimate year 1978
    Total resources 208545000mt ore
    Commodity Subtype Grade units Group Importance Year
    Molybdenum Mo 0.033 wt-pct Molybdenum Secondary 1978
    Copper Cu 0.32 wt-pct Copper Primary 1978
  • Type In-situ
    Estimate year 1981
    Total resources 152443000mt ore
    Commodity Subtype Grade units Group Importance Year
    Molybdenum Mo 0.035 wt-pct Molybdenum Secondary 1981
    Copper Cu 0.3 wt-pct Copper Primary 1981
  • Type In-situ
    Estimate year 1986
    Total resources 155691000mt ore
    Commodity Subtype Grade units Group Importance Year
    Molybdenum Mo 0.036 wt-pct Molybdenum Secondary 1986
    Copper Cu 0.31 wt-pct Copper Primary 1986
  • Type In-situ
    Name mineralized material
    Estimate year 2009
    Demonstrated 2349000000mt
    Remarks Freeport-McMoRan 2009 10-K, pp. 40, 127.
    Commodity Subtype Grade units Group Importance Year
    Molybdenum 0.022 wt-pct Molybdenum Secondary 2009
    Copper 0.2 wt-pct Copper Primary 2009

Comments on the reserve resource information

  • 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.

Workings at the site

  • Type of workings Surface
    Name of workings Open Pit Operation
    Area 500HA
    Length 1524M
    Width 914.4M
    Field Value
    MAS Development Schedule # 1
    Mining Record # 1
    Status of Mining Method ACTUAL
    Mining Method BENCH (BERM)
    Swell Factor .75
    Percent Waste Rock 42.8
    Avg. Overburden Thickness 61
    Primary Material Cover SAND, GRAVEL
    Secondary Material Cover M-HARD ROCKS
    Tertiary Material Cover HARD ROCKS
    Hardness of Ore HARD ROCKS
    Avg. Bench Height (meters) 15
    Max. Pit Slope (degrees) 40
    Capacity 78020
    Capacity Units MT ORE/DAY
    Preprod. Stripping Vol. 72200
    Unit Production Cost .66
    Units of Production $/MT ORE
    Operating Days per Year 365
    Operating Shifts per Day 3
    Year of Information 1988

Comments on the workings information

  • Open Pit, Mine Area Approximated From Map

Comments on other 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.

Comments on development

  • Owned By Duval Corp. Until 1986. Part Of The Deposit Is Mined By Solution.

Reference information

Bibliographic references

  • Production

    Nickel News. Issue 32/52. 8/6/97. P.12.

  • Geology

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

  • 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.

  • 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.

  • 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.

  • Reserve-Resource

    Securities and Exchange Commission Form 10k For Pennzoil Company For Year Ending Dec. 31, 1981.

  • 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.

  • 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.

  • Reserve-Resource

    Cyprus-Amax Minerals Co., Sec Form 10-K Rept, 12/31/93, P.7.

  • Reserve-Resource

    Cyprus Amax Minerals Co., 1994 Form 10-K, P.2.

  • 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.

  • Reserve-Resource

    Cyprus Minerals Company 1987 Form 10-K Report, Page 3.

  • Geology

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

  • Reserve-Resource

    Cyprus Amax Minerals Company 1995 10-K, P.2-4.

  • Deposit

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

  • Deposit

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

  • Deposit

    Emj June 75 Pg 98 (Good) Emj Mine Directory 1975 (Good)

  • Deposit

    Emj August 70 Pg 70 Flot Mill-Feed Cap 85000 T

  • Deposit

    Arizona Pay Dirt. Pennzoil Pushing Duval Asset Sale. December 1984, Pp. 8a-9a.

  • Deposit

    Cyprus Minerals Company. 1986 Form 10-K Report, P.1, 3-7.

  • Deposit

    Cyprus Minerals Company. 1987 Annual Report

  • Deposit

    Cyprus Minerals Company. Press Release, Feb. 18, 1986.

  • Deposit

    Rocky Mountain Pay Dirt. April 1986, P. 22a.

  • Deposit

    Southwestern Pay Dirt. March 1986, P. 4a-5a.

  • Deposit

    Southwestern Pay Dirt. April 1986, P. 8a-10a.

  • Deposit

    Southwestern Pay Dirt. July 1986, P. 18a-19a.

  • Deposit

    Southwestern Pay Dirt. November 1986, P. 10a-11a.

  • Deposit

    Southwestern Pay Dirt. August 1987, P. 18a-19a.

  • Deposit

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

  • Deposit

    Southwestern Pay Dirt, 1/91, P.12a.

  • Deposit

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

  • Deposit

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

  • Deposit

    Mining Magazine, 7/91, P.5.

  • Deposit

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

  • Deposit

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

  • Deposit

    Cyprus Amax Minerals Co., News Release, 12/31/93, 1pp.

  • Deposit

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

  • Deposit

    Aiken and West, 1978, Az Geol Soc Digest Vii, P. 117-128.

  • Deposit

    Keith, 1974, Abm Bull 189, P. 138.

  • Deposit

    Lynch, 1966, In Titley and Hicks, Univ Of Az Press.

  • Deposit

    Greeley, 1978, Admr Spec Rept No 2.

  • Deposit

    Engineering And Mining Journal, October, 1987, P. 12.

  • 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.

  • Other Database

    Cimri

  • Production

    Aiken and West, 1978; Sawyer And Others, 1992.

  • Reserve-Resource

    Greeley, 1978; Sawyer And Others, 1992.

General comments

Subject category Comment text
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.

Reporter information

Type Date Name Affiliation Comment
Reporter 26-AUG-97 Kreidler, Terry J. U.S. Bureau of Mines
Reporter 01-MAR-83 Peterson, Jocelyn A. U.S. Geological Survey
Updater 01-NOV-90 Berger, Mary A. U.S. Geological Survey
Updater 01-DEC-93 Orris, Greta J. U.S. Geological Survey
Editor 25-AUG-10 Schruben, Paul U.S. Geological Survey Revised production and reserves.

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Current status (per MSHA)

StatusActive since 04/01/1986
MSHA mine ID0200144
Mine name (MSHA)Freeport-McMoRan Sierrita Ops.
Current operatorFreeport-McMoRan Sierrita Ops.
Current controller (parent)Freeport-McMoRan Inc
Mine typeSurface (Metal / non-metal)

MSHA cross-reference per the original MRDS record. Mine status and operator reflect MSHA's last published Mines export (February 2025); MSHA's public bulk feed has been unavailable since, so this may be out of date. See the Mine Data Retrieval System for current status.

Open MSHA's Mine Data Retrieval System for inspections, accidents, and violations for this mine.

Operator history (post-MRDS)

MRDS records operators as of each record's last update (≤ 2019). Some of the operators listed here have since changed hands or dissolved:

  • Cyprus Amax Minerals Co. — now part of Subsidiary of Freeport-McMoRan (2007)
    Formed by merger of Cyprus Minerals and AMAX in 1993; acquired by Phelps Dodge in 1999; Phelps Dodge acquired by Freeport-McMoRan in 2007.

Curated by qvyshift.com from publicly-reported M&A activity (SEC filings, press releases, USGS Mineral Yearbooks). Not authoritative — verify against primary sources before relying on it. The MSHA panel above is the current authoritative source for actively-permitted mines.

External references

Maps centered on this site

Authoritative Arizona resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.