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Esperanza Mine group [old], Pima Mining District, Sierrita Mountains, Pima County, Arizona, USAi
Regional Level Types
Esperanza Mine group [old]Group of Mines
Pima Mining DistrictMining District
Sierrita MountainsMountain Range
Pima CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
31° 51' 45'' North , 111° 6' 59'' West
Latitude & Longitude (decimal):
31.86250,-111.11639
GRN:
N22W67
Type:
Group of Mines
Köppen climate type:
BSk : Cold semi-arid (steppe) climate
Nearest Settlements:
PlacePopulationDistance
Green Valley21,391 (2011)11.6km
Arivaca Junction1,090 (2011)15.9km
Amado295 (2011)17.9km
Sahuarita25,707 (2017)18.5km
East Sahuarita1,622 (2006)19.9km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Old Pueblo Lapidary ClubTucson, Arizona44km
Tucson Gem and Mineral SocietyTucson, Arizona44km
Mindat Locality ID:
36246
Long-form identifier:
mindat:1:2:36246:2
GUID (UUID V4):
0


A former surface and underground Pb-Zn-Cu-Ag-Au-Mo mine group located in southern sec. 8, the SW ¼ sec. 9, southern sec. 16, northern sec. 17 & North-central sec. 21, T.18S., R.12E, on land of unknown status. Owned at times, or in part, by the Chesterfield Copper Co.; Elston Esperanza Co.; the Blanche Rose Mining Co.; Pike; and the Magnet Copper Co.

Included at various times the mines listed under this file plus the Crown King and Tiger Mine groups.

Mineralization is partly oxidized, relatively weak and irregular, quartz-calcite fissure veins containing spotty sulfides in Cretaceous sedimentary-volcanic rocks. Locally low-grade, disseminated copper and molybdenum mineralization in siliceous, brecciated Laramide quartz monzonite porphyry, Cretaceous rocks, and quartz masses.

Workings include numerous realtively shallow shafts, adits, pits and small open cuts. Originally prospected in Spanish colonial times. Intermittent production occurred mainly from the early 1900's through 1943, on a small scale, producing about 2,000 tons of ore averaging some 12% Pb, 4% Cu, 12 oz. Ag/T and minor Zn & Au. For later production under Duval, see the Esperanza open pit mine.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

Mineral list contains entries from the region specified including sub-localities

7 valid minerals.

Detailed Mineral List:

ⓘ Calcite
Formula: CaCO3
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Galena
Formula: PbS
ⓘ Kaolinite
Formula: Al2(Si2O5)(OH)4
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Sphalerite
Formula: ZnS

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘKaolinite9.ED.05Al2(Si2O5)(OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ KaoliniteAl2(Si2O5)(OH)4
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ CalciteCaCO3
Oⓘ KaoliniteAl2(Si2O5)(OH)4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
AlAluminium
Alⓘ KaoliniteAl2(Si2O5)(OH)4
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ KaoliniteAl2(Si2O5)(OH)4
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ GalenaPbS
Sⓘ PyriteFeS2
Sⓘ SphaleriteZnS
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ PyriteFeS2
CuCopper
Cuⓘ ChalcopyriteCuFeS2
ZnZinc
Znⓘ SphaleriteZnS
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10234530

Localities in this Region

USA

Other Regions, Features and Areas containing this locality

Mexico
North AmericaContinent
North America PlateTectonic Plate

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.

References

Ransome, F.L. (1922) Ore deposits of the Sierrita Mountains, Pima County, Arizona, in Contributions to Economic Geology (Short Papers and Preliminary Reports), 1921 - Part I.--Metals and Nonmetals except Fuels: U.S. Geological Survey Bulletin 725J: 427.
USGS Twin Buttes Quadrangle topo map.
Arizona Bureau of Mines file data
MRDS database Dep. ID file #10234530, MAS ID #0040190221.
Anderson, C.A., and Kupfer, D.H. (1945) Report on the properties of the Amargosa Molybdenum and Copper Corporation, Pima County, Arizona: U.S. Geological Survey Open-File Report [unnumbered], 20 p., 8 sheets.
Keith, Stanton B. (1974), Arizona Bureau of Geology & Mineral Technology, Geological Survey Branch Bull. 189, Index of Mining Properties in Pima County, Arizona: 135 (Table 4).
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