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Joker Group Prospect, Circle Mining District, Yukon-Koyukuk Census Area, Alaska, USAi
Regional Level Types
Joker Group ProspectProspect
Circle Mining DistrictMining District
Yukon-Koyukuk Census AreaCensus Area
AlaskaState
USACountry

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Latitude & Longitude (WGS84):
65° 25' 55'' North , 146° 46' 8'' West
Latitude & Longitude (decimal):
Köppen climate type:
Mindat Locality ID:
198245
Long-form identifier:
mindat:1:2:198245:2
GUID (UUID V4):
0


Location: The Joker Group can be reached via an 8 mile long dirt road that starts in Circle Hot Springs. The claims are above the confluence of Bottom Dollar and Half -Dollar Creeks. The coordinates are for the approximate center of the Joker Group claims.
Geology: The bedrock in the Joker claims groups is primarily porphyritic igneous rock containing large K-spar phenocrysts. Visible gold is found in the quartz veins. Both lode and placer gold are found at these claims (Vetter, 1995). Wiltse and others (1995) mapped the bedrock in the area as Cretaceous chloritized porphyritic (hornblende) biotite monzogranite to syenogranite. They also mapped a mafic dike in the area of the 88 Group claims which is described as black to dark gray, aphanitic to slightly porphyritic, with major plagioclase, augite, hornblende and magnetite. The granite is exposed along several ditches where it is deeply weathered and fractured. Abundant visible gold is seen in the stockwork veining. The light yellow color of the gold suggests a high silver content. Placer gold from the creeks below has a fineness of 750. Sampling in the vicinity of the Joker claims failed to delineate any significant extent to the stockwork veining; however, the trend of the stockwork veining is parallel to the ditch exposure, which is not as continuous as that at the 88 Group (Bakke,1991).
Workings: Surface samples taken.
Age: Mineralization is later than the Cretaceous granitic host rocks.

Commodities (Major) - Au
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 1 - Elements
ⓘNative Gold1.AA.05Au

List of minerals for each chemical element

AuGold
Auⓘ Native GoldAu

Other Databases

Link to USGS - Alaska:CI030

Other Regions, Features and Areas containing this locality


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References

 
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