Unnamed (south of upper Long Creek)

Prospect, Inactive

Commodities and mineralogy

Main commodities Au; Cu
Other commodities Cr; Ni; Pt
Ore minerals chalcopyrite; chromite; pyrite

Geographic location

Quadrangle map, 1:250,000-scale HE
Quadrangle map, 1:63,360-scale A-6
Latitude 63.18
Longitude -149.69
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at an elevation of 400 feet south of upper Long Creek. The site is in sec. 17, T. 20 S., R. 11 W., of the Fairbanks Meridian. The location is accurate to within 1 mile. This is loc. 12 of Hawley and others (1969); loc. 35 of Hawley and Clark (1974).

Geologic setting

Geologic description

The country rocks in the area of this prospect consist largely of sheared, Devonian serpentinite that forms lenticular and podiform tectonic blocks as much as several hundred meters in size. The deposit is in serpentinite, and consists of pyrite-rich pods, locally accompanied by chalcopyrite and gold-rich zones. Local high platinum, chrome, and nickel values have also been reported. Samples contain up to 0.3 ppm gold, 1,500 ppm chromium, 3,000 ppm copper, 1,500 ppm nickel, and a trace of platinum (Hawley and others, 1969).
Geologic map unit (-149.692290791863, 63.1795244925991)
Mineral deposit model Podiform chromite (Cox and Singer, 1986; model 8a)
Mineral deposit model number 8a
Age of mineralization The copper and chromium minerals probably were syngenetic with their Devonian ultramafic hostrock, and may have been partly redistributed during serpentinization.

Production and reserves

Workings or exploration Surface sampling only. Local high platinum, chrome, and nickel values have also been reported. Samples contain up to 0.3 ppm gold, 1,500 ppm chromium, 3,000 ppm copper, 1,500 ppm nickel, and a trace of platinum (Hawley and others, 1969).
Indication of production None
Reserve estimates None of the sulfide bodies appears to be of any significant size.

References