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Germolis prospect (Rodon; Rodonick; Germolie; Cormolis), Fiddletown (Oleta), Fiddletown Mining District (Oleta Mining District), Amador County, California, USAi
Regional Level Types
Germolis prospect (Rodon; Rodonick; Germolie; Cormolis)Prospect
Fiddletown (Oleta)- not defined -
Fiddletown Mining District (Oleta Mining District)Mining District
Amador CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
38° 28' 37'' North , 120° 45' 15'' West
Latitude & Longitude (decimal):
38.47694,-120.75417
GeoHash:
G#: 9qf4uht2r
GRN:
N26W68
Type:
Prospect
Köppen climate type:
Csa : Hot-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Fiddletown235 (2011)3.0km
River Pines379 (2011)7.8km
Plymouth960 (2017)7.9km
Amador City189 (2017)8.8km
Drytown167 (2011)9.6km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Amador County Gem & Mineral SocietySutter Creek, California10km
El Dorado County Mineral and Gem SocietyPlacerville, California28km
Gold Country Treasure SeekersPlacerville, California28km
Calaveras Gem & Mineral SocietyAngels Camp, California49km
Mindat Locality ID:
73638
Long-form identifier:
mindat:1:2:73638:4
GUID (UUID V4):
0


A Mn occurrence/prospect located in the NW¼ sec. 10, T7N, R11E, MDM, about 3.35 km S of Fiddletown, N of the Deadman Fork Dry Creek, on private land. Discovered in 1942. Owned by Paul Germolis, California (1974). MRDS database stated accuracy for this location is 500/1,000 meters (2 USGS MRDS database files). Part of the Plymouth Consolidated.

Local rocks include Paleozoic marine rocks, undivided, unit 4 (Western Sierra Nevada).

Workings include surface openings.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 valid minerals.

Detailed Mineral List:

ⓘ Alleghanyite
Formula: Mn2+5(SiO4)2(OH)2
ⓘ Rhodochrosite
Formula: MnCO3
ⓘ Spessartine
Formula: Mn2+3Al2(SiO4)3
ⓘ Tephroite
Formula: Mn2+2SiO4

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 5 - Nitrates and Carbonates
ⓘRhodochrosite5.AB.05MnCO3
Group 9 - Silicates
ⓘTephroite9.AC.05Mn2+2SiO4
ⓘSpessartine9.AD.25Mn2+3Al2(SiO4)3
ⓘAlleghanyite9.AF.45Mn2+5(SiO4)2(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ AlleghanyiteMn52+(SiO4)2(OH)2
CCarbon
Cⓘ RhodochrositeMnCO3
OOxygen
Oⓘ AlleghanyiteMn52+(SiO4)2(OH)2
Oⓘ RhodochrositeMnCO3
Oⓘ SpessartineMn32+Al2(SiO4)3
Oⓘ TephroiteMn22+SiO4
AlAluminium
Alⓘ SpessartineMn32+Al2(SiO4)3
SiSilicon
Siⓘ AlleghanyiteMn52+(SiO4)2(OH)2
Siⓘ SpessartineMn32+Al2(SiO4)3
Siⓘ TephroiteMn22+SiO4
MnManganese
Mnⓘ AlleghanyiteMn52+(SiO4)2(OH)2
Mnⓘ RhodochrositeMnCO3
Mnⓘ SpessartineMn32+Al2(SiO4)3
Mnⓘ TephroiteMn22+SiO4

Other Databases

Link to USGS MRDS:10211028

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

U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0060050006 & 0060050328.
Ransome, Frederick Leslie (1900), Description of the Mother Lode district, California: USGS Geological Atlas, Mother Lode, folio No. 63, 11 pp.: sheet 1, section 1.
Trask, Parker Davies, Ivan F. Wilson & F.S. Simons (1943), Manganese deposits of California – a summary report: California Division Mines Bulletin 125: 102-103
Trask, Parker Davies (1950) Geologic description of the manganese deposits of California. California Division of Mines Bulletin 152, 378 pp.: 30.
Carlson, D.W. & W.B. Clark (1954), Mines and Minerals of Amador County, California: California Journal of Mines and Geology (Report 50): 50(1): 268.
Hewett, Donnel Foster, Chesterman, Charles Wesley, Troxel, Bennie Wyatt (1961) Tephroite in California manganese deposits. Economic Geology, 56 (1). 39-58 doi:10.2113/gsecongeo.56.1.39p.49
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 60, 320, 361.
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
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