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Cloud Occurrence, Innoko Mining District, Yukon-Koyukuk Census Area, Alaska, USAi
Regional Level Types
Cloud OccurrenceOccurrence
Innoko Mining DistrictMining District
Yukon-Koyukuk Census AreaCensus Area
AlaskaState
USACountry

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Latitude & Longitude (WGS84):
63° 12' 3'' North , 155° 58' 37'' West
Latitude & Longitude (decimal):
63.20083,-155.97694
GeoHash:
G#: be1pd9m59
GRN:
N43W52
Type:
Occurrence
Köppen climate type:
Dfc : Subarctic climate
Nearest Settlements:
PlacePopulationDistance
McGrath344 (2017)33.3km
Mindat Locality ID:
196960
Long-form identifier:
mindat:1:2:196960:6
GUID (UUID V4):
0


See Won - North (MD021), Won - South (MD024), Win (MD060), and Gemini (MD023) prospects.
Location: The Cloud occurrence is located on a northeast facing spur of Cloudy Mountain at an elevation af approximately 2,400 feet (731 m) in Section 27, T. 26 S., R. 15 E., of the Kateel River Meridian. The prospect is located to within 1,000 feet (300 m).
Geology: The geologic description is sketchy and based on a brief industry report (Anaconda Minerals Company, written communication, 1984). The Cloud prospect is not as well documented as the Win (MD060), Won-North (MD021), Won-South (MD024), and Gemini (MD023) tin-silver prospects in the Medfra quadrangle. The Cloud prospect consists of quartz-tourmaline (cassiterite-arsenopyrite-complex Pb-Sb-Zn-Ag sulfosalt) veins in hornfels about 2,000 feet (600 m) from the contact with a small monzonite stock. Vein orientations and dimensions were not given. The hornfels is thermally altered Kuskokwim Group of Upper Cretaceous age (Patton and others, 1980). Age is judged to be Late Cretaceous-early Tertiary, based on dated, genetically related intrusives nearby (Bundtzen and Miller, 1997). No specific assay data is available for this summary.
Workings: The prospect area was discovered in 1983 by Duval Corporation while following up stream sediment anomaly data released by the U.S. Geological Survey (King and others, 1980; 1983; Patton and others, 1980). No specific assay data is available.
Age: Age is judged to be Late Cretaceous-early Tertiary, based on dated, genetically related intrusives nearby (Bundtzen and Miller, 1997).
Reserves: None.

Commodities (Major) - Ag, Sn; (Minor) - As, Bi, Pb, Sb, Zn
Development Status: No
Deposit Model: Tin polymetallic vein (Cox and singer, 1986; model no. 20b)

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


3 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘArsenopyrite2.EB.20FeAsS
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
ⓘCassiterite4.DB.05SnO2
Unclassified
ⓘ'Tourmaline'-AD3G6 (T6O18)(BO3)3X3Z

List of minerals for each chemical element

BBoron
Bⓘ TourmalineAD3G6 (T6O18)(BO3)3X3Z
OOxygen
Oⓘ CassiteriteSnO2
Oⓘ QuartzSiO2
Oⓘ TourmalineAD3G6 (T6O18)(BO3)3X3Z
SiSilicon
Siⓘ QuartzSiO2
SSulfur
Sⓘ ArsenopyriteFeAsS
FeIron
Feⓘ ArsenopyriteFeAsS
AsArsenic
Asⓘ ArsenopyriteFeAsS
SnTin
Snⓘ CassiteriteSnO2

Other Databases

Link to USGS - Alaska:MD059

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

Bundtzen, T.K., and Miller, M.L., 1997, Precious metals associated with Late Cretaceous-early Tertiary igneous rocks of southwestern Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 242-286. King, H.D., Cooley, E.F., and Spiesman, D.L., 1983, Distribution of gold and silver in nonmagnetic and magnetic heavy mineral concentrate and minus 80 mesh stream sediment samples and ash of aquatic bryophyte samples, Medfra quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-811K. King, H.D., Risoli, D.A., and Galland, W.W., 1983, Distrbution and abundance of molybdenum, tin, and tungsten in heavy mineral concentrate samples, Medfra quadrangle, Alaska: U.S. Geological Survey Open File Report 80-811J. King, H.D., Risoli, D.A., Cooley, E.F., O'Leary, R.M., Speckman, W.A., Speisman, D.L., and Galland, D.W., 1980, Final results and statistical summary of analyses of geochemical samples from the Medfra quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-811F, 134 pages. Patton, W.W. Jr., Moll, E.J., Dutro, J.T., Jr., Silberman, M.L., and Chapman, R.M., 1980, Preliminary geologic map of the Medfra quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-811, one sheet at 1:250,000 scale.
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