Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat Articles
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsThe ElementsUsersBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Sierrita Mine (Duval-Sierrita Mine; Duval Esperanza Mine; Sierrita Open Pit Mine), Batamote Hills, Pima District (Olive District; Mineral Hill District; Twin Buttes District), Sierrita Mts, Pima Co., Arizona, USAi
Regional Level Types
Sierrita Mine (Duval-Sierrita Mine; Duval Esperanza Mine; Sierrita Open Pit Mine)Mine (Active)
Batamote HillsGroup of Hills
Pima District (Olive District; Mineral Hill District; Twin Buttes District)Mining District
Sierrita MtsMountain Range
Pima Co.County
ArizonaState
USACountry

This page is currently not sponsored. Contact us for sponsorship opportunities.
Key
Latitude & Longitude (WGS84):
31° 52' 14'' North , 111° 7' 59'' West
Latitude & Longitude (decimal):
Owned/operated by:
Locality type:
Mine (Active) - last checked 2018
Nearest Settlements:
PlacePopulationDistance
Green Valley21,391 (2011)13.3km
Arivaca Junction1,090 (2011)17.3km
Amado295 (2011)19.2km
Sahuarita25,707 (2017)19.3km
East Sahuarita1,622 (2006)20.9km


A former large output surface Cu-Mo-Ag-Zn-Pb-Au mine located in the SE ¼ sec. 7, the SW ¼ sec. 8, the NW ¼ sec. 17 & the NE ¼ sec. 18, T.18S., R.12E., 5½ miles WSW of Twin Buttes and 20 miles SW of Tucson, on private land. Discovered 1960. Produced initially in 1970. Owned by the Duval Sierrita Corp (subsidiary of Pennzoil) until 1986; then, owned by Cyprus Mines Co. since 1990. An open pit copper-molybdenum-rhenium mine located near Tucson. Part of the deposit is mined by solution.

Mineralization is a V-shaped ore body that is part of the Esperanza-Sierrita deposit. Ore is superficially oxidized, disseminated chalcopyrite and pyrite with copper and molybdenum sulfides in seams and fractures in a large V-shaped orebody containing Triassic to late Laramide andesite porphyry, quartz monzonite, quartz latite, quartz diorite, and quartz monzonite porphyry, as well as a breccia pipe. Ore control was the fractures and seams plus the breccia pipe. Alteration is potassic, phyllic, argillic with supergene effects, propylitic. Associated rock units are the Ruby Star Quartz Monzonite Porphyry; and the Harris Ranch Quartz Monzonite.

Local structures include fractures that strike N50-85E and N50-25W that are steeply dipping.

Workings are an open pit operation 1,524 meters long and 914.4 meters wide. Pre-mine stripping began in 1968 with initial production in 1970. Starting in 1970, production through 1972 has been some 68,000,000 tons of Cu-Mo ore. In 1980 produced 90,000 tons of ore and 135,000 tons of waste daily. Average ore grade was about 0.24% Cu, 0.03 oz. Ag/T, 0.016% MOS2, and trace amounts of Au, Pb & Zn.

The Duval/Sierrita mine was developed by the Duval Corporation, originally, the Duval Texas Sulfur Company. The company diversified into copper in 1959, when it purchased the Esperanza orebody, which had been explored, but considered too poor to develop by Kennecott Copper Company, a few years earlier. Duval received an $83 million loan to develop the low-grade (0.28 percent copper) Sierrita deposit, located near the Esperanza mine. When it opened in 1970, Sierrita had an annual capacity of 80,000 tons of metallic copper.

The Sierrita Concentrator beginning operation in 1970 at a designed capacity of 72,000 STPD (short tons per day). Subsequent additions and modifications expanded capacity to 90,000 STPD. Ore Grade 0.32% Cu., 0.030% Mo. Daily Tons Milled 90,000 STPD annual copper production 94,600 tons; annual Molybdenum production 15,000,000 lbs.; and, annual silver production of 1,135,000 Ounces. A smelter for molybdenum was operated at the Duval/Sierrita Complex.

Regions containing this locality

North America PlateTectonic Plate
Sonoran Desert, North AmericaDesert

Select Mineral List Type

Standard Detailed Strunz Dana Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


22 valid minerals.

Detailed Mineral List:

Anhydrite
Formula: CaSO4
Reference: Dana Slaughter Minerals Specimen
Bassanite
Formula: Ca(SO4) · 0.5H2O
Habit: Tiny, sub-hedral, fibrous crystals
Description: Occurs in veinlets filled with quartz in hydrothermally altered diorite and quartz diorite porphyry.
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 130.
Bornite
Formula: Cu5FeS4
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Calcite
Formula: CaCO3
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 130.
Chalcocite
Formula: Cu2S
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Chalcopyrite
Formula: CuFeS2
Reference: Keith, Stanton B. (1974), AZ Bur. of Geol. & Min. Technology, Geol. Survey Br. Bull. 189, Index of Mining Properties in Pima County, AZ: 138 (Table 4); Arizona Bureau of Mines file data.
'Chlorite Group'
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 130.
Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Cuprite
Formula: Cu2O
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Epidote
Formula: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Description: Product of hydrothermally altered dioritic rocks.
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 215.
Fluorite
Formula: CaF2
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Galena
Formula: PbS
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Gypsum
Formula: CaSO4 · 2H2O
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 383.
Magnetite
Formula: Fe2+Fe3+2O4
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Malachite
Formula: Cu2(CO3)(OH)2
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Marcasite
Formula: FeS2
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Molybdenite
Formula: MoS2
Reference: Keith, Stanton B. (1974), AZ Bur. of Geol. & Min. Technology, Geol. Survey Br. Bull. 189, Index of Mining Properties in Pima County, AZ: 138 (Table 4); Arizona Bureau of Mines file data.
Pyrite
Formula: FeS2
Reference: Keith, Stanton B. (1974), AZ Bur. of Geol. & Min. Technology, Geol. Survey Br. Bull. 189, Index of Mining Properties in Pima County, AZ: 138 (Table 4); Arizona Bureau of Mines file data.
Quartz
Formula: SiO2
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 130.
Sphalerite
Formula: ZnS
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
'Stilbite subgroup'
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 383.
Tennantite
Formula: Cu6Cu4(Fe2+,Zn)2As4S12S
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Tenorite
Formula: CuO
Reference: MRDS database Dep. ID file #10039631, MRDS ID #M050531.
Zoisite
Formula: Ca2Al3[Si2O7][SiO4]O(OH)
Description: Alteration product of dioritic rocks.
Reference: Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 432.

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
Bornite2.BA.15Cu5FeS4
Chalcocite2.BA.05Cu2S
Chalcopyrite2.CB.10aCuFeS2
Galena2.CD.10PbS
Marcasite2.EB.10aFeS2
Molybdenite2.EA.30MoS2
Pyrite2.EB.05aFeS2
Sphalerite2.CB.05aZnS
Tennantite2.GB.05Cu6Cu4(Fe2+,Zn)2As4S12S
Group 3 - Halides
Fluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
Cuprite4.AA.10Cu2O
Magnetite4.BB.05Fe2+Fe3+2O4
Quartz4.DA.05SiO2
Tenorite4.AB.10CuO
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Malachite5.BA.10Cu2(CO3)(OH)2
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Anhydrite7.AD.30CaSO4
Bassanite7.CD.45Ca(SO4) · 0.5H2O
Gypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
Chrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
Epidote9.BG.05a{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Zoisite9.BG.10Ca2Al3[Si2O7][SiO4]O(OH)
Unclassified Minerals, Rocks, etc.
'Chlorite Group'-
'Stilbite subgroup'-

List of minerals arranged by Dana 8th Edition classification

Group 2 - SULFIDES
AmBnXp, with (m+n):p = 2:1
Chalcocite2.4.7.1Cu2S
AmBnXp, with (m+n):p = 3:2
Bornite2.5.2.1Cu5FeS4
AmXp, with m:p = 1:1
Galena2.8.1.1PbS
Sphalerite2.8.2.1ZnS
AmBnXp, with (m+n):p = 1:1
Chalcopyrite2.9.1.1CuFeS2
AmBnXp, with (m+n):p = 1:2
Marcasite2.12.2.1FeS2
Molybdenite2.12.10.1MoS2
Pyrite2.12.1.1FeS2
Group 3 - SULFOSALTS
3 <ø < 4
Tennantite3.3.6.2Cu6Cu4(Fe2+,Zn)2As4S12S
Group 4 - SIMPLE OXIDES
A2X
Cuprite4.1.1.1Cu2O
AX
Tenorite4.2.3.1CuO
Group 7 - MULTIPLE OXIDES
AB2X4
Magnetite7.2.2.3Fe2+Fe3+2O4
Group 9 - NORMAL HALIDES
AX2
Fluorite9.2.1.1CaF2
Group 14 - ANHYDROUS NORMAL CARBONATES
A(XO3)
Calcite14.1.1.1CaCO3
Group 16a - ANHYDROUS CARBONATES CONTAINING HYDROXYL OR HALOGEN
Malachite16a.3.1.1Cu2(CO3)(OH)2
Group 28 - ANHYDROUS ACID AND NORMAL SULFATES
AXO4
Anhydrite28.3.2.1CaSO4
Group 29 - HYDRATED ACID AND NORMAL SULFATES
AXO4·xH2O
Bassanite29.6.1.1Ca(SO4) · 0.5H2O
Gypsum29.6.3.1CaSO4 · 2H2O
Group 58 - SOROSILICATES Insular, Mixed, Single, and Larger Tetrahedral Groups
Insular, Mixed, Single, and Larger Tetrahedral Groups with cations in [6] and higher coordination; single and double groups (n = 1, 2)
Epidote58.2.1a.7{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Zoisite58.2.1b.1Ca2Al3[Si2O7][SiO4]O(OH)
Group 74 - PHYLLOSILICATES Modulated Layers
Modulated Layers with joined strips
Chrysocolla74.3.2.1Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
Group 75 - TECTOSILICATES Si Tetrahedral Frameworks
Si Tetrahedral Frameworks - SiO2 with [4] coordinated Si
Quartz75.1.3.1SiO2
Unclassified Minerals, Mixtures, etc.
'Chlorite Group'-
'Stilbite subgroup'-

List of minerals for each chemical element

HHydrogen
H GypsumCaSO4 · 2H2O
H BassaniteCa(SO4) · 0.5H2O
H Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
H ZoisiteCa2Al3[Si2O7][SiO4]O(OH)
H ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
H MalachiteCu2(CO3)(OH)2
CCarbon
C CalciteCaCO3
C MalachiteCu2(CO3)(OH)2
OOxygen
O GypsumCaSO4 · 2H2O
O BassaniteCa(SO4) · 0.5H2O
O QuartzSiO2
O CalciteCaCO3
O Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
O ZoisiteCa2Al3[Si2O7][SiO4]O(OH)
O ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
O CupriteCu2O
O MagnetiteFe2+Fe23+O4
O MalachiteCu2(CO3)(OH)2
O TenoriteCuO
O AnhydriteCaSO4
FFluorine
F FluoriteCaF2
AlAluminium
Al Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Al ZoisiteCa2Al3[Si2O7][SiO4]O(OH)
Al ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
SiSilicon
Si QuartzSiO2
Si Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Si ZoisiteCa2Al3[Si2O7][SiO4]O(OH)
Si ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
SSulfur
S PyriteFeS2
S ChalcopyriteCuFeS2
S MolybdeniteMoS2
S GypsumCaSO4 · 2H2O
S BassaniteCa(SO4) · 0.5H2O
S BorniteCu5FeS4
S ChalcociteCu2S
S GalenaPbS
S MarcasiteFeS2
S SphaleriteZnS
S TennantiteCu6Cu4(Fe2+,Zn)2As4S12S
S AnhydriteCaSO4
CaCalcium
Ca GypsumCaSO4 · 2H2O
Ca BassaniteCa(SO4) · 0.5H2O
Ca CalciteCaCO3
Ca Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Ca ZoisiteCa2Al3[Si2O7][SiO4]O(OH)
Ca FluoriteCaF2
Ca AnhydriteCaSO4
FeIron
Fe PyriteFeS2
Fe ChalcopyriteCuFeS2
Fe Epidote{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Fe BorniteCu5FeS4
Fe MagnetiteFe2+Fe23+O4
Fe MarcasiteFeS2
Fe TennantiteCu6Cu4(Fe2+,Zn)2As4S12S
CuCopper
Cu ChalcopyriteCuFeS2
Cu BorniteCu5FeS4
Cu ChalcociteCu2S
Cu ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
Cu CupriteCu2O
Cu MalachiteCu2(CO3)(OH)2
Cu TennantiteCu6Cu4(Fe2+,Zn)2As4S12S
Cu TenoriteCuO
ZnZinc
Zn SphaleriteZnS
Zn TennantiteCu6Cu4(Fe2+,Zn)2As4S12S
AsArsenic
As TennantiteCu6Cu4(Fe2+,Zn)2As4S12S
MoMolybdenum
Mo MolybdeniteMoS2
PbLead
Pb GalenaPbS

References

Sort by

Year (asc) Year (desc) Author (A-Z) Author (Z-A)
Lynch, D.W. (1966), The economic geology of the Esperanza mine and vicinity, in S.R. Titley and C.L. Hicks (editors), Geology of the porphyry copper deposits, southwestern North America, University of Arizona Press, Tucson: 267-279.
World Mining (1972) Duval Sierrita mills 71,252 tons per day: World Mining: 8(6): 39.
Keith, Stanton B. (1974), Arizona Bureau of Geology & Mineral Technology, Geological Survey Branch Bull. 189, Index of Mining Properties in Pima County, Arizona: 138 (Table 4).
Aiken, D.M., and West, R.J. (1978) Some geologic aspects of the Sierrita-Esperanza copper-molybdenum deposit, Pima County, Arizona, in Jenney, J.P., and Hauck, H.R., eds., Proceedings of the Porphyry Copper Symposium, Tucson, Arizona, March 18-20, 1976: Arizona Geological Society Digest: 11: 117-128.
Greeley (1978) Arizona Department of Mineral Resources Special Report #2.
Barter, C.F., and Kelly, J.L. (1982) Geology of the Twin Buttes mineral deposit, Pima mining district, Pima County, Arizona, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 407-432.
Titley, Spencer R. (1982) 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, University of Arizona Press: 387-406.
West, R.J., and Aiken, D.M. (1982) Geology of the Sierrita-Esperanza deposit, Pima mining district, Pima County, Arizona, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press: 433-465.
Mining Annual Review (1985): 55, 94, 118, 329.
Southwestern Pay Dirt (1986): March, 1986: 4A-5A.
Rocky Mountain Pay Dirt (1986): April, 1986: 22A.
Southwestern Pay Dirt (1986): July, 1986: 18A-19A
Southwestern Pay Dirt (1986): November, 1986: 10A-11A.
Southwestern Pay Dirt (1987): August, 1987: 18A-19A.
Engineering and Mining Journal (1987), October 1987: 12.
Minerals Yearbook (1988) - Mining & Quarrying Trends: 31.
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 pp.
Dillard, Gary (1993) Cyprus Cuts 220 at Sierrita in Fight to Reduce Unit Costs, Southwestern Pay Dirt: 8/93: 12A.
Dillard, Gary (1993) Benefits Starting from $350 Million Program, Southwestern Pay Dirt: 9/93: 4A, 5A.
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd. ed.: 130, 215, 383, 432.
Arizona Bureau of Mines file data.
MRDS database Dep. ID file #10039631, MRDS ID #M050531; and Dep. ID #10137304, MAS ID #0040190050; and, Dep. ID #10210570, MAS ID #0040190051; and, Dep. ID #10305094, MAS ID #0040190048.

USGS MRDS Record:10039631
This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
 
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2019, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: July 17, 2019 21:41:13 Page generated: June 24, 2019 15:44:38
Go to top of page