Unnamed (ridge between Beaver and Tolstoi Creeks)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Zn
Other commodities Au; Cu; Sb
Ore minerals iron oxide; manganese oxide
Gangue minerals tourmaline

Geographic location

Quadrangle map, 1:250,000-scale ID
Quadrangle map, 1:63,360-scale D-2
Latitude 62.98371
Longitude -156.82805
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 1,350 feet on a knob that is about 0.8 mile northeast of hill 2340. It is about 0.2 mile south of the northeast corner of section 3, T. 33 N., R. 40 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description

This occurrence consists of rubble of iron-oxide-stained breccia in hornfels that is probably related to the Cretaceous Beaver Mountains pluton. Manganese-oxide-stained rosettes of tourmaline in the hornfels may be related to a nearby, potassically-altered andesite-porphyry dike. The occurrence is about 2 miles north of the northern contact of the Beaver Mountains pluton (Miller and Bundtzen, 1994; Miller, Bundtzen, and Gray, 2005). Grab samples contain up to 55.0 parts per million (ppm) silver, 1,000 ppm zinc, 500 ppm copper, 100 ppm antimony, and 100 parts per billion (ppb) gold (Bundtzen and Laird, 1982).
Geologic map unit (-156.83040909087, 62.9830658530618)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c
Age of mineralization Probably related to the Beaver Mountains pluton which has been dated at 70.1 Ma (Bundtzen and Laird, 1982).
Alteration of deposit Rocks altered to tourmaline greisen.

Production and reserves

Workings or exploration Limited surface sampling was conducted in 1979 (Bundtzen and Laird, 1982).
Indication of production None

References