Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Cu
Other commodities Ba
Ore minerals chalcopyrite; pyrite
Gangue minerals calcite; garnet; pyroxene

Geographic location

Quadrangle map, 1:250,000-scale TK
Quadrangle map, 1:63,360-scale C-3
Latitude 62.7304
Longitude -148.1383
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Waterfall occurrence is between an elevation of about 4,000 to 4,500 feet on the upper part of a north-flowing tributary to the Susitna River. It is approximately 1 mile northwest of Mount Watana and 2 3/4 miles west of Watana Lake in the east 1/2 of sec. 33, T. 31 N., R. 7 E., Seward Meridian. The location is accurate to within 1/4 mile.

Geologic setting

Geologic description

The rocks are this occurrence are upper Paleozoic sedimentary rocks that are altered to garnet-pyroxene-chalcopyrite-calcite-pyrite skarn; locally there is intercalated very-dark-red-weathering pyritic chert (J. Schmidt, written communication, 2001). U.S. Geological Survey samples of the skarn contain up to 568 parts per million copper, 1.8 parts per million silver, and 3,800 parts per million barium (J. Schmidt, written communication, 2001).
Geologic map unit (-148.140531495146, 62.7299326304362)
Mineral deposit model Cu Skarn (Cox and Singer, 1986; model 18b)
Mineral deposit model number 18b
Alteration of deposit The skarn, host rock contains garnet, pyroxene, calcite, and pyrite (J. Schmidt, written communication, 2001). Pyritic chert weathers dark red.

Production and reserves

Workings or exploration Only surface sampling by U.S. Geological Survey (J. Schmidt, written communication, 2001).
Indication of production None