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Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Latitude & Longitude (WGS84):
33° 52' 10'' North , 114° 17' 45'' West
Latitude & Longitude (decimal):
Type:
Deposit first discovered:
1979
Köppen climate type:
Nearest Settlements:
PlacePopulationDistance
Poston285 (2011)16.3km
Quartzsite3,626 (2017)23.7km
Bouse996 (2011)27.7km
Big River1,327 (2011)30.7km
Parker3,046 (2017)31.2km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Quartzsite Roadrunners Gem & Mineral ClubQuartzsite, Arizona24km
Mindat Locality ID:
10338
Long-form identifier:
mindat:1:2:10338:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Copperstone Open pit; Continental Silver Claim group; Copperstone Underground Mine


A large former Au-Ag-Baryte (trace) property located in the NE¼ sec. 12, T6N, R20W, 18 miles (ca. 29 km) S of Parker on the E side of the Colorado River, 12 miles (ca. 19 km) N of Quartzsite, on Bureau of Land Management-administered land. The site consists of 290 unpatented mining claims leased by Cyprus, covering 5800 acres (23.47 km²) of federal land. Discovered 1979. First produced 1987. Owned by Cyprus Gold Co., a subsidiary of the Cypress Minerals Co. (Don Patch retains royalty rights)(1988). Operated by Morrison-Knudsen (1989).

Mineralization is a tabular deposit striking N30W and dipping 32NE with ore control by faults and brecciation and detachment faulting. Alteration is sericitization and some chloritization. Local structures include a probable fault separating Jurassic metamorphosed volcanic rocks and overlying sedimentary breccias derived from them. Moon Mountains Detachment Fault. The presence of quartz, hematite, and chrysocolla is a good indicator of gold mineralization.

The gold is in a breccia unit above a listric fault, in quartz latite below the listric fault, and in basalt plugs. The basalt plugs have the least mineralization. The listric fault is in the upper plate of a detachment fault. The mineralized contact zone extends horizontally for 3,000 feet (ca. 914 m) and at least 1,000 feet (ca. 305 m) down dip and is generally several tens of feet thick.

This mine will feature an open pit and development of an underground mine. The bench open pit will be 360 feet (ca. 110 m) deep. Produced 1,953 kg Au (1988).

The life of this project is estimated at 7–9 years. No previous mining occurred at this site. Underground development was stopped by Cyprus in 1990 due to lower gold prices and because of caving ground conditions, which required costly support methods. Cyprus may consider reaching the former underground mining targets from the surface. Copperstone was to have been the largest gold producer in Arizona and will more than double the state's 1986 gold output of 42,556 oz.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

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


Mineral List


15 valid minerals.

Detailed Mineral List:

Baryte
Formula: BaSO4
Calcite
Formula: CaCO3
Chalcopyrite
Formula: CuFeS2
'Chlorite Group'
Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Fluorite
Formula: CaF2
Goethite
Formula: Fe3+O(OH)
Hematite
Formula: Fe2O3
Kaolinite
Formula: Al2(Si2O5)(OH)4
Magnetite
Formula: Fe2+Fe3+2O4
Malachite
Formula: Cu2(CO3)(OH)2
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
Native Gold
Formula: Au
'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
Pyrite
Formula: FeS2
Pyrolusite
Formula: Mn4+O2
Quartz
Formula: SiO2
Quartz var. Amethyst
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Chalcopyrite2.CB.10aCuFeS2
Pyrite2.EB.05aFeS2
Group 3 - Halides
Fluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
Goethite4.00.Fe3+O(OH)
Magnetite4.BB.05Fe2+Fe3+2O4
Hematite4.CB.05Fe2O3
Quartz
var. Amethyst
4.DA.05SiO2
4.DA.05SiO2
Pyrolusite4.DB.05Mn4+O2
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Malachite5.BA.10Cu2(CO3)(OH)2
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Baryte7.AD.35BaSO4
Group 9 - Silicates
Muscovite9.EC.15KAl2(AlSi3O10)(OH)2
var. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Kaolinite9.ED.05Al2(Si2O5)(OH)4
Chrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Unclassified
'Chlorite Group'-
'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8

List of minerals for each chemical element

HHydrogen
H ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
H GoethiteFe3+O(OH)
H KaoliniteAl2(Si2O5)(OH)4
H MalachiteCu2(CO3)(OH)2
H MuscoviteKAl2(AlSi3O10)(OH)2
H Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CCarbon
C CalciteCaCO3
C MalachiteCu2(CO3)(OH)2
OOxygen
O Quartz var. AmethystSiO2
O BaryteBaSO4
O CalciteCaCO3
O ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
O GoethiteFe3+O(OH)
O HematiteFe2O3
O KaoliniteAl2(Si2O5)(OH)4
O MagnetiteFe2+Fe23+O4
O MalachiteCu2(CO3)(OH)2
O MuscoviteKAl2(AlSi3O10)(OH)2
O PyrolusiteMn4+O2
O QuartzSiO2
O Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
O Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
FFluorine
F FluoriteCaF2
NaSodium
Na Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
AlAluminium
Al ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Al KaoliniteAl2(Si2O5)(OH)4
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Al Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Si Quartz var. AmethystSiO2
Si ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Si KaoliniteAl2(Si2O5)(OH)4
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si QuartzSiO2
Si Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Si Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SSulfur
S BaryteBaSO4
S ChalcopyriteCuFeS2
S PyriteFeS2
KPotassium
K MuscoviteKAl2(AlSi3O10)(OH)2
K Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca CalciteCaCO3
Ca FluoriteCaF2
Ca Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MnManganese
Mn PyrolusiteMn4+O2
FeIron
Fe ChalcopyriteCuFeS2
Fe GoethiteFe3+O(OH)
Fe HematiteFe2O3
Fe MagnetiteFe2+Fe23+O4
Fe PyriteFeS2
CuCopper
Cu ChalcopyriteCuFeS2
Cu ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cu MalachiteCu2(CO3)(OH)2
BaBarium
Ba BaryteBaSO4
AuGold
Au Native GoldAu

Other Databases

Link to USGS MRDS:10056413
Link to USGS MRDS:10259110

Other Regions, Features and Areas containing this locality


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