Unnamed (in locally-named Sargent Creek)

Prospect, Inactive

Commodities and mineralogy

Main commodities Au; Cu; Fe
Other commodities Ag
Ore minerals azurite; chalcopyrite; magnetite; malachite
Gangue minerals calcite; epidote; garnet; quartz

Geographic location

Quadrangle map, 1:250,000-scale IL
Quadrangle map, 1:63,360-scale A-5
Latitude 59.1369
Longitude -154.654
Nearby scientific data Find additional scientific data near this location
Location and accuracy This lode prospect is at an elevation of about 1,800 feet in locally-named Sargent Creek (Richter and Herreid, 1965). Sargent Creek was called Crevice Creek by Jasper (1953, 1956). The prospect is near the center of the N1/2 SW1/4 sec. 15, T. 12 S., R. 32 W., Seward Meridian. The prospect coincides with number 7 of Richter and Herreid (1965) and may correspond approximately wth locality 19 of Detterman and Cobb (1972). The location is accurate within 500 feet.

Geologic setting

Geologic description

The country rocks at this prospect are chiefly intermediate and basic volcanic rocks of the Jurassic Talkeetna Formation (Richter and Herreid, 1965; Detterman and Reed, 1980). The deposit was largely snow covered when visited by Richter and Herreid, but they described dump samples of epidote-garnet tactite (skarn), garnet-magnetite skarn, massive magnetite, and massive magnetite-calcite rock. The samples were copper-stained, presumably by malachite and azurite, and contained chalcopyrite.
Geologic map unit (-154.656115786815, 59.1362096241572)
Mineral deposit model Fe skarn, Cu skarn (Cox and Singer, 1986; models 18d, 18b).
Mineral deposit model number 18d, 18b
Age of mineralization Probably Jurassic, the age of the nearby Pilot Knob granodiorite (IL041) (Richter and Herreid, 1965).
Alteration of deposit Contact metasomatism. Oxidation of copper.

Production and reserves

Workings or exploration Test pits were largely snow covered when visited by Richter and Herreid (1965); the claim-owner (Sargent) reported good showings of disseminated chalcopyrite. The deposit was probably covered by the McNeil (IL043) claims.
Indication of production None