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Big Seven Mine, Copperopolis, Foothill Copper Belt, Calaveras County, California, USAi
Regional Level Types
Big Seven MineMine
CopperopolisCensus-designated Place
Foothill Copper BeltBelt
Calaveras CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
38° 0' 15'' North , 120° 38' 4'' West
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Copperopolis3,671 (2011)2.7km
Angels Camp2,677 (2012)10.9km
Tuttletown668 (2011)15.4km
Vallecito442 (2011)17.0km
Jamestown3,433 (2011)19.4km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Calaveras Gem & Mineral SocietyAngels Camp, California11km
Amador County Gem & Mineral SocietySutter Creek, California46km
Mindat Locality ID:
74890
Long-form identifier:
mindat:1:2:74890:9
GUID (UUID V4):
0


A former lode Au-Zn-Pb mine located in the SE¼SE¼ sec. 22 & in the NE¼NE¼ sec. 27, T5N, R11E, MDM, 2.6 km (1.6 miles) NNE of Copperopolis, along Black Creek (Christian Gulch) on the E slope of Big Seven Ridge. Operated prior to and during 1936. MRDS database stated accuracy for this location is 500 meters.

Mineralization is a vein deposit hosted in schist. The ore body strikes NW and dips NE at a width of 91.44 meters. The mineralized zone is about 300 feet wide and consists of altered calcite, quartz, baryte and sericite schist. Local rocks include Mesozoic volcanic rocks, unit 2 (Western Sierra Foothills and Western Klamath Mountains).

Workings include underground openings comprised of a 110 foot inclined shaft with levels at 50 and 100 feet. The 50 foot level has a 30 foot westward crosscut and from the 110 foot level a 75 foot drift trends southward. An 80 foot adit has been driven southward (the topo map reflects 3 shaft symbols).

Production data are found in: Logan, Clarence August and Franke, H. (1936); Clark, Wm. B. & P.A. Lydon (1962).

No production record found.

24% of Au on average is free. The remainder is in sulfides. A small piece of ore, mainly quartz and baryte, ran $12 per ton of Au (period values).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


8 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Sphalerite2.CB.05aZnS
Galena2.CD.10PbS
Pyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
Quartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
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

List of minerals for each chemical element

HHydrogen
H MuscoviteKAl2(AlSi3O10)(OH)2
H Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CCarbon
C CalciteCaCO3
OOxygen
O BaryteBaSO4
O CalciteCaCO3
O MuscoviteKAl2(AlSi3O10)(OH)2
O QuartzSiO2
O Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
AlAluminium
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si QuartzSiO2
Si Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
S BaryteBaSO4
S GalenaPbS
S PyriteFeS2
S SphaleriteZnS
KPotassium
K MuscoviteKAl2(AlSi3O10)(OH)2
K Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca CalciteCaCO3
FeIron
Fe PyriteFeS2
ZnZinc
Zn SphaleriteZnS
BaBarium
Ba BaryteBaSO4
AuGold
Au GoldAu
PbLead
Pb GalenaPbS

Other Databases

Link to USGS MRDS:10028802

Other Regions, Features and Areas containing this locality


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