Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Cu
Other commodities Sb; Zn

Geographic location

Quadrangle map, 1:250,000-scale PM
Quadrangle map, 1:63,360-scale A-1
Latitude 55.101
Longitude -160.008
Nearby scientific data Find additional scientific data near this location
Location and accuracy This site is located on Nagai Island at the head of Sanborn Harbor approximately 1.5 miles south of Macks Head. It is referred to as PMRGX-1 in Wilson and others (1988, locality 51).The location is accurate to within 1,200 feet.

Geologic setting

Geologic description

This occcurrence represents a group of geochemical anomalies in the late Cretaceous Shumagin Formation near a contact with the Shumagin batholith (Wilson and others, 1988). Of five samples collected, one is pale-green, fine-grained sulfide-bearing sandstone, one is leucocratic granite(?) of the Shumagin batholith, and three are sandstone and siltstone of the Shumagin Formation. The samples were reported to be anomalous in copper, silver, antimony, and zinc.
Geologic map unit (-160.010036565759, 55.1001815404077)

Production and reserves

Workings or exploration Rock samples 84AWs145a-c, 84AWs152, and 84ADt169 collected by the U.S. Geological Survey in the mid-1980s were reported to be anomalous in copper, silver, antimony, and zinc (Wilson and others, 1988).
Indication of production None

Additional comments

This site is located on land selected or patented by, or interim-conveyed to, the Aleut Corporation.