Pupinski

Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Sn
Other commodities Cu; W
Ore minerals cassiterite; chalcopyrite; galena
Gangue minerals magnetite; tourmaline

Geographic location

Quadrangle map, 1:250,000-scale MD
Quadrangle map, 1:63,360-scale A-4
Latitude 63.239
Longitude -154.719
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Pupinski prospect is located near the saddle north of Encio Gulch at an elevation of 1,500 feet (457 m) in Section 18, T. 26 S., R. 22 E., of the Kateel River Meridian. The reporter visited the site in 1989 and 1996.

Geologic setting

Geologic description

The Pupinski prospect is along the southeastern margin of the Nixon Fork monzonite stock (Bundtzen and Miller, 1997). It consists of a magnetite-sulfide skarn that differs from the Nixon Fork Mine showings (MD062) in that gold is absent and copper, silver, tin and minor tungsten values are elevated. Cassiterite is locally abundant in late stage veins, and in association with tourmaline. The Pupinski deposit has only been briefly explored. Age of mineralization is probably Upper Cretaceous based on isotopic age (68.0 Ma) of Nixon Fork pluton (Moll and others, 1981; Bundtzen and Miller, 1997). Grab samples collected at the site contain up to 262 ppm silver, 3.00 percent copper, 0.35 percent tin, and 120 ppm tungsten (Bundtzen and Miller, 1997; Ted Almasy, personal communication, 1998).
Geologic map unit (-154.721321888176, 63.2383936658132)
Mineral deposit model Polymetallic tin (Cox and Singer, 1986; model 20b).
Mineral deposit model number 20b
Age of mineralization Age of mineralization is probably Upper Cretaceous, based on isotopic age of Nixon Fork pluton (Moll and others, 1981).
Alteration of deposit Sericite and tourmaline.

Production and reserves

Workings or exploration The Pupinski deposit has only been briefly explored, mainly by Central Alaska Gold Company in the early 1990s (Ted Almasy, personal communication, 1998). Grab samples collected at the site contain up to 262 ppm silver, 3.00 percent copper, 0.35 percent tin, and 120 ppm tungsten (Bundtzen and Miller, 1997; Ted Almasy, personal communication, 1998).
Indication of production None
Reserve estimates None.

Additional comments

See Win Deposit (MD060). The Pupinski prospect is on land conveyed to Doyon Ltd. For further information, contact Doyon Ltd at 210 1st Ave., Fairbanks, Alaska, 99701.

References

MRDS Number A012430

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.
Reporters Bundtzen, T.K. (Pacific Rim Geological Consulting)
Last report date 6/7/1998