Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; pyrite; sphalerite
Gangue minerals barite

Geographic location

Quadrangle map, 1:250,000-scale MK
Quadrangle map, 1:63,360-scale A-5
Latitude 58.0033
Longitude -155.6568
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is best exposed in a southward-flowing drainage at the base of a volcanic neck in the Kejulik Mountains. It is about 6 miles south-southwest of Kejulik Pass at an elevation of about 1,250 feet in the SE1/4 sec. 22, T. 25 S., R. 39 W., of the Seward Meridian. The location is accurate within one-half mile.

Geologic setting

Geologic description

This occurrence consists of highly bleached rocks at the base of a Pleistocene and late Tertiary volcanic neck. The neck consists of lava flows, breccias, tuffs, and domes of andesite and dacite (Riehle and others, 1993). The bleached rocks contain both disseminated and vein pyrite exposed in the valley floor. Panned concentrate samples collected by Church and Bennett (1989) contain pyrite, pyrite, sphalerite, and barite. The samples contain up to 300 parts per million (ppm) copper, 150 ppm zinc, 50 ppm cobalt, 50 ppm nickel, 10 ppm molybdenum, and 2.7 ppm cadmium (Church, Riehle, and Goldfarb, 1993).
Geologic map unit (-155.658889514397, 58.0025938765423)
Mineral deposit model Polymetallic vein; concealed porphyry copper? (Cox and Singer, 1986; model 22c, 17).
Mineral deposit model number 22c, 17
Age of mineralization Pleistocene and late Tertiary based on the age of the host rocks.
Alteration of deposit Host rocks are bleached.

Production and reserves

Workings or exploration Apparently only geochemical sampling by government geologists.
Indication of production None



Reporters F.H. Wilson, S.E. Church, and D.P. Bickerstaff (U.S. Geological Survey)
Last report date 8/31/2005