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Fall Ravine Mine, Duncan Peak, Duncan Peak Mining District, Placer County, California, USAi
Regional Level Types
Fall Ravine MineMine
Duncan PeakPeak
Duncan Peak Mining DistrictMining District
Placer CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
39° 8' 28'' North , 120° 29' 7'' West
Latitude & Longitude (decimal):
39.14111,-120.48528
GeoHash:
G#: 9qfqdm3m3
GRN:
N27W67
Type:
Mine
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Kingvale143 (2011)20.6km
Sunnyside-Tahoe City1,557 (2011)28.0km
Alta610 (2011)29.0km
Dutch Flat160 (2011)31.2km
Foresthill1,483 (2011)31.7km
Mindat Locality ID:
85324
Long-form identifier:
mindat:1:2:85324:7
GUID (UUID V4):
0


A former lode Au-Pb occurrence/mine located in the SE¼SE¼ sec. 14, T15N, R13E, MDM, 2.8 km (1.7 miles) ESE of Duncan Peak (coordinates of record), on the W wall of Duncan Canyon, on private land within a National Forest area. MRDS database stated accuracy for this location is 500 meters.

Mineralization is a vein deposit hosted in slate. The ore body strikes NW and dips 60NE. The vein is 3 feet thick and contains 4% sulfides. Local rocks include Paleozoic marine rocks, undivided, unit 4 (Western Sierra Nevada).

Workings include underground openings with a length of 198.12 meters and an overall depth of 106.68 meters, and comprised of a shaft, tunnel (adit ?) and drifting.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


3 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘGold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
ⓘGalena2.CD.10PbS
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2

List of minerals for each chemical element

OOxygen
Oⓘ QuartzSiO2
SiSilicon
Siⓘ QuartzSiO2
SSulfur
Sⓘ GalenaPbS
AuGold
Auⓘ GoldAu
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10034880

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

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

(n.d.) Minerals Availability System (MAS), U.S. Bureau of Mines.file #0060610839
Crawford, James John (1894), Twelfth report of the State Mineralogist: California Mining Bureau. (Report 12): 12: 208.
Lindgren, Waldemar (1897), Description of the gold belt; description of the Truckee sheet: USGS Geological Atlas, Truckee folio (Folio No. 39), 8 pp.
Waring, Clarence A. (1917), Placer County: Report 15 of the State Mineralogist, California State Mining Bureau (Report 15): 15: 339.
Logan, Clarence August (1936), Gold Mines of Placer County: California Journal of Mines and Geology, California Division Mines (Report 32): 32(1): 44.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
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