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Last Chance-Copper Coin Mine group (Smith Mine), Barry M. Goldwater Air Force Range, Copper Mountains, La Posa Mining District (Wellton Mining District; Wellton Hills Mining District), Wellton Hills-Copper Mountains, Yuma County, Arizona, USAi
Regional Level Types
Last Chance-Copper Coin Mine group (Smith Mine)- not defined -
Barry M. Goldwater Air Force RangeMountain Range
Copper MountainsMountain Range
La Posa Mining District (Wellton Mining District; Wellton Hills Mining District)Mining District
Wellton Hills-Copper MountainsMountain Range
Yuma CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
32° 28' 51'' North , 114° 0' 9'' West
Latitude & Longitude (decimal):
32.48083,-114.00250
GeoHash:
G#: 9mybvbcyt
GRN:
N22W69
Köppen climate type:
BWh : Hot deserts climate
Nearest Settlements:
PlacePopulationDistance
Tacna602 (2011)24.5km
Wellton2,936 (2017)25.3km
Fortuna Foothills26,265 (2011)43.1km
Buckshot153 (2017)53.4km
Dateland416 (2011)55.6km
Mindat Locality ID:
33559
Long-form identifier:
mindat:1:2:33559:2
GUID (UUID V4):
0


A former underground Cu-Au-Ag-Fe-Mo mine group located in South-central sec. 10, T11S, R17W (protracted) (Tinajas Altas 15 minute topo map), 18 miles S of Wellton, on a military reservation. Owned at times, or in part, by Pedstel & Everhandy; Smith; and, Bannard.

Mineralization is small pockets containing finely divided gold and irregular bunches of secondary copper minerals and iron oxides, with gypsum and jarosite, in brecciated quartz and sericite, in a fissure zone in Mesozoic granite. The ore zone is 30.48 meters long, 0.91 meters wide, strikes S53E, and dips 60E.

Workings include a shaft(s) and ytunnel operations. These mines were worked sporadically in the 1920's and 1930's. They produced some 30 tons of ore averaging about 7% Cu, 0.4 oz. Au/T, and 0.1 oz. Ag/T.

Workings include a shaft(s) and tunnel operations. They were worked intermittently from the early 1910's through 1939. They produced some 145 tons of ore averaging about 2% Cu, 0.3 oz. Au/T and 1.4 oz. Ag/T.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

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

5 valid minerals.

Detailed Mineral List:

ⓘ Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Description: In irregular bunches.
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Jarosite
Formula: KFe3+3(SO4)2(OH)6
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Gold
Formula: Au
Description: Finely divided in small pockets.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘJarosite7.BC.10KFe3+3(SO4)2(OH)6
ⓘGypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘChrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1

List of minerals for each chemical element

HHydrogen
Hⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ JarositeKFe33+(SO4)2(OH)6
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
Oⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ JarositeKFe33+(SO4)2(OH)6
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
AlAluminium
Alⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ JarositeKFe33+(SO4)2(OH)6
KPotassium
Kⓘ JarositeKFe33+(SO4)2(OH)6
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ GypsumCaSO4 · 2H2O
FeIron
Feⓘ JarositeKFe33+(SO4)2(OH)6
CuCopper
Cuⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
AuGold
Auⓘ Native GoldAu

Other Databases

Link to USGS MRDS:10027227

Localities in this Region

USA
  • Arizona
    • Yuma County
      • Wellton Hills-Copper Mountains
        • La Posa Mining District (Wellton Mining District; Wellton Hills Mining District)

Other Regions, Features and Areas containing this locality

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

Arizona Bureau of Geology and Mining Technology file data.
MRDS database Dep. ID file #10027227, MRDS ID #M002550; and, Dep. ID #10137747, MAS ID #0040270260.
(1933) Geology and Mineral Deposits of Southern Yuma County, Arizona. University of Arizona Bulletin 134. Arizona Bureau of Minesp.167
Keith, Stanton B. (1978) Index of Mining Properties in Yuma County, Arizona. University of Arizona Bulletin 192. Bureau of Geology and Mineral Technology p.160 - Table 4
Niemuth, Nyal J., Phillips, Ken A. (1992, July) Copper Oxide Resources. Open-file Report 92-10. Arizona Department of Mines and Mineral Resourcesp.18 - Table 1
(n.d.) ADMMR Mines Database, Arizona Geological Survey.
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