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Unnamed Prospect (ARDF - ID036; west wall of Yankee Creek), Innoko Mining District, Yukon-Koyukuk Census Area, Alaska, USAi
Regional Level Types
Unnamed Prospect (ARDF - ID036; west wall of Yankee Creek)- not defined -
Innoko Mining DistrictMining District
Yukon-Koyukuk Census AreaCensus Area
AlaskaState
USACountry

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Latitude & Longitude (WGS84):
62° 59' 6'' North , 156° 24' 50'' West
Latitude & Longitude (decimal):
62.98500,-156.41389
GeoHash:
G#: be0y2dnfh
GRN:
N42W55
Köppen climate type:
Dfc : Subarctic climate
Mindat Locality ID:
202183
Long-form identifier:
mindat:1:2:202183:9
GUID (UUID V4):
0


Location: This prospect is west of Yankee Creek at an elevation of about 1,500 feet. It is near the northwest corner of section 1, T. 33 N ., R 38 W., of the Seward Meridian. The location is accurate.
Geology: This prospect is in a highly altered, northeast-trending mafic (ultramafic?) dike that intrudes sandstone and siltstone of the Upper Cretaceous, Kuskokwim Group (Bundtzen and Laird, 1983; Miller and Bundtzen, 1994). The dike is brown to tan in color and is almost completely altered to silica-carbonate minerals and mariposite. Rubble-crop suggests that the dike is 6 to 25 feet wide; it it can be traced along strike for about 500 feet in old prospect pits and rubble crop (Bundtzen and Laird, 1983). A grab sample of the altered dike contained 5.0 parts per million (ppm) silver, 200 ppm nickel, and 2,000 ppm chromium (Bundtzen and Laird, 1983). This occurrence is an example of chromium, nickel, and occasional precious metal enrichment that occurs in altered mafic and ultramafic? dikes in the Ganes -Yankee Creek fault zone and in other areas of the Iditarod quadrangle. The abundant chromite and magnesiochromite found in panned concentrates from Yankee Creek (ID037) and Ganes Creek (ID011) may be derived from occurrences of this type (Bundtzen, Cox, and Veach, 1987).
Workings: The altered dike at this unnamed prospect has been explored by several old prospect pits.
Age: Undated; similar mafic dikes near the DeCourcy Mountain Mine (ID158) have 40K/40Ar dates of 71 to 76 Ma (Miller and Bundtzen, 1994).
Alteration: Pervasive alteration of mafic to ultramafic dikes to silica and carbonate minerals and mariposite.

Commodities (Major) - Ag, Cr; (Minor) - Ni
Development Status: None

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


1 valid mineral.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Phengite9.EC.15KAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
ⓘvar. Mariposite9.EC.15K(Al,Cr)2(Al,Si)4O10(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Hⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
OOxygen
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Oⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
MgMagnesium
Mgⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
AlAluminium
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Alⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
SiSilicon
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Siⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Kⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
CrChromium
Crⓘ Muscovite var. MaripositeK(Al,Cr)2(Al,Si)4O10(OH)2
FeIron
Feⓘ Muscovite var. PhengiteKAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2

Other Databases

Link to USGS - Alaska:ID036

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 Laird, G.M., 1983, Geologic map of the Iditarod D-1 quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Professional Report 78, scale 1:63,360. Bundtzen, T.K., Cox, B.C., and Veach, N.C., 1987, Heavy mineral provenance studies in the Iditarod and Innoko districts, western Alaska: Process Mineralogy VII, The Metallurgical Society, p. 221-246. Miller, M.L., and Bundtzen, T.K., 1994, Generalized geologic map of the Iditarod quadrangle, Alaska showing potassium-argon, major oxide, trace element, fossil, paleocurrent, and archeological sample localities: U.S. Geological Survey Miscellaneous Field Studies Map MF-2219-A, 48 pages; 1 sheet, scale 1:250,000.
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