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Maryland Mine, Minnesota Flat, Alleghany Mining District (Forest Mining District), Sierra County, California, USAi
Regional Level Types
Maryland MineMine
Minnesota FlatFlat
Alleghany Mining District (Forest Mining District)Mining District
Sierra CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
39° 26' 29'' North , 120° 50' 4'' West
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Washington185 (2011)9.6km
Downieville282 (2011)13.1km
Pike134 (2011)14.0km
Camptonville158 (2011)18.4km
Sierra City221 (2011)22.1km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Nevada County Gem & Mineral SocietyGrass Valley, California31km
Mindat Locality ID:
93418
Long-form identifier:
mindat:1:2:93418:0
GUID (UUID V4):
0


A former lode Au occurrence/mine located in the E½ (estimated) sec. 10, T18N, R10E, MDM, 0.9 km (0.6 mile) SSW of Minnesota Flat (site), along the N canyon wall of the Middle Yuba River (1½ miles S of Alleghany), on National Forest land. MRDS database stated accuracy for this location is 1,000 meters.

Mineralization is a vein deposit hosted in schist. The ore body is 5.49 meters thick. The lode is up to 18 feet thick and is composed of stringers & quartz lenses in a shear zone striking 20-37NW. A poorly defined northerly vertical fault with an horizontal offset of less than 100 feet occurs at an average distance of 2 feet below the quartz, and has a strongly marked shear plane separating the shear zone from less altered schist to the E. The shear zone is less sharp on the hanging wall side of the shear zone. The schist near the quartz is pyritized in places. Local rocks include Mesozoic gabbroic rocks, unit 2 (undivided).

Workings include surface and underground openings comprised of 2 adits and several pits.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


5 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Pyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
Quartz4.DA.05SiO2
Group 9 - Silicates
Talc9.EC.05Mg3Si4O10(OH)2
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 TalcMg3Si4O10(OH)2
H Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
O MuscoviteKAl2(AlSi3O10)(OH)2
O QuartzSiO2
O TalcMg3Si4O10(OH)2
O Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
MgMagnesium
Mg TalcMg3Si4O10(OH)2
AlAluminium
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si QuartzSiO2
Si TalcMg3Si4O10(OH)2
Si Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
S PyriteFeS2
KPotassium
K MuscoviteKAl2(AlSi3O10)(OH)2
K Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
FeIron
Fe PyriteFeS2
AuGold
Au Native GoldAu

Other Databases

Link to USGS MRDS:10034791

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

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