Unnamed (ridge between the middle and east forks in Broxson Gulch)

Occurrence, Active

Commodities and mineralogy

Main commodities Ag; Ni
Other commodities Au; Cu
Ore minerals pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-5
Latitude 63.3484
Longitude -146.0802
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of 4,900 feet on the ridge between the locally named middle and east forks of the stream(s) in Broxson Gulch (see figure 2 of Rose, 1965). The occurrence is at the southeast corner of section 18, T. 18 S., R. 9 E, Fairbanks Meridian. This location corresponds to locality 20 on figure 2 of Rose (1965).

Geologic setting

Geologic description

The rock at this site appears to be sandstone or quartzite of the Slana Spur Formation of Late Paleozoic age faulted into Upper Triassic peridotite (Rose, 1965).
The deposit consists of pyrrhotite disseminated in sandstone. A sample assayed 0.2 percent nickel, 0.18 ounce of silver per ton, and small amounts of copper and gold (Rose, 1965, p. 31). Stream-sediment sample 284 collected below the occurrence contained 420 parts per million nickel (Rose, 1965).
Geologic map unit (-146.08246596274, 63.3479810430978)
Mineral deposit model Pyrrhotite-bearing replacement? of sandstone in fault contact with mafic-ultramafic rocks.
Alteration of deposit The sandstone apparently is hornfelsed to quartzite.

Production and reserves

Workings or exploration A sample contained 0.2 parts per million nickel. The occurrence is on active MAN Resources claims.
Indication of production None

References

MRDS Number A011817

References

Reporters W.T. Ellis (Alaska Earth Science), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)
Last report date 6/19/2001