Little Clearwater lode

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Ag
Ore minerals chalcocite; chalcopyrite; malachite
Gangue minerals calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale A-6
Latitude 63.1492
Longitude -146.8837
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Little Clearwater lode is at an elevation of about 4,850 feet about 0.7 mile southwest of peak 5315 at the south end of the Clearwater Mountains; it is in the SE1/4SE1/4 section 24, T. 20.S., R. 4 E., Fairbanks Meridian. The occurrence corresponds to locality A36 of Kurtak and others (1992), locality 3 in figure 4 of Cobb (1979 [OFR 79-238]), and locality 6 in table 2 of Nokleberg and others (1991).

Geologic setting

Geologic description

The rock at the occurrence is propylitized basalt of the Nikolai Greenstone of Late Triassic age (Nokleberg and others, 1991). The deposit consists of copper-bearing quartz-calcite veins in the weakly altered basalt. Reported copper minerals are chalcopyrite, chalcocite, and malachite. Sample 1414 from metabasalt assayed 0.34 ounce of silver per ton and 1.08 percent copper; gold is present in a near-background amount (10 parts per billion) (Kurtak and others, 1992, table A32, p. 165).
Geologic map unit (-146.885962897574, 63.1487580710163)
Mineral deposit model Basaltic Cu (Cox and Singer, 1986; model 23).
Mineral deposit model number 23
Age of mineralization The deposit is probably either Cretaceous or early Tertiary in age (see MH060, MH087, or MH100).
Alteration of deposit Propylitic alteration.

Production and reserves

Workings or exploration U.S. Bureau of Mines sample 1414 contained 1.08 percent copper and 0.34 ounce of silver per ton (Kurtak and others, 1992, table A32).
Indication of production None

Additional comments

The mineralized zones are small and mostly in rubble.