Unnamed (west of Broxson Gulch)

Prospect, Active

Commodities and mineralogy

Main commodities Ag; Cu
Other commodities Au
Ore minerals bornite; chalcopyrite; malachite; pyrite
Gangue minerals chlorite; epidote

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-5
Latitude 63.3167
Longitude -146.1988
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at an elevation of about 4,600 feet in the headwaters of an east-flowing tributary to the stream(s) in Broxson Gulch, in the NW1/4NW1/4 section 34, T. 18 S., R. 8 E., Fairbanks Meridian. The locality corresponds to locality 5 on figure 3 of Rose (1966 [ADMM GR 20]) and to locality 42 in table 2 of Nokleberg and others (1991).

Geologic setting

Geologic description

The rock at this prospect consists of dacite agglomerate of the Slana Spur Formation of Late Paleozoic age (Rose, 1966 [ADMM GR 20, figure 3]; Nokleberg and others, 1991). Nokleberg and others proposed that the rock is meta-andesite porphyry.
The prospect is on a mineralized shear zone that strikes N85W and dips 35 degrees southwest; the shear zone can be traced for several hundred feet. Locally, the sheared andesite is altered to a chlorite-epidote rock that contains pyrite, chalcopyrite, and bornite. Some of the mineralized rock is coated with malachite. A foot-wide sample collected by Rose (1966 [ADMM GR 20]) assayed 2.95 percent copper and 2.2 ounces of silver per ton. Samples 79IL047A and B collected by the U.S. Geological Survey assayed as much as 3.8 percent copper, 50 parts per million (ppm) silver and 0.1 ppm gold (Nokleberg and others, 1991).
Geologic map unit (-146.201064457592, 63.3162780054253)
Mineral deposit model Low-sulfide copper vein.
Age of mineralization Late Paleozoic or younger; the mineralized shear zone cuts Upper Paleozoic rocks.
Alteration of deposit Chlorite-epidote alteration of the volcanic host rock; local oxidation of copper minerals.

Production and reserves

Workings or exploration
The prospect was staked by a Moneta-Porcupine Company prospector in 1964. Surface workings include a shallow trench and several small pits. A sample across a one-foot width assayed 2.95 percent copper and 2.2 ounces of silver per ton (Rose, 1966 [ADMM GR 20]).
The prospect is on active MAN Resources claims.
Indication of production None

References