Unnamed (northwest of lower Jay Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au; Cu
Other commodities Ag
Ore minerals hematite; pyrite; pyrrhotite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale TK
Quadrangle map, 1:63,360-scale D-2
Latitude 62.8412
Longitude -147.8345
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 3,680 feet, northwest of lower Jay Creek. It is 0.6 mile north of hill 4008, in the SW1/4 sec. 19, T. 32 N., R. 9 E., Seward Meridian. The location is accurate to within 1/4 mile. The occurrence is locality B30 of Kurtak and others (1992).

Geologic setting

Geologic description

The rocks in the vicinity of this occurrence are felsic(?) and intermediate to mafic metavolcanic rocks, chlorite schist, and sericite schist (Csejtey and others, 1978; Kurtak and others, 1992). The rocks are cut by quartz veins, locally stained tan-orange, that contain finely disseminated hematite, pyrrhotite, and pyrite (Kurtak and others, 1992). The U.S. Bureau of Mines sampled the stained areas in 1988 (Kurtak and others, 1992). Pyritic schist contains up to 212 parts per million zinc, and hematite-rich rock contains up to 124 parts per million copper. Gold values vary up to 10 parts per billion and silver values to 0.5 parts per million . Intermediate intrusive rocks in the area sampled by the U.S. Geological Survey contain up to 550 parts per million copper, 1 part per million silver, and 200 parts per million arsenic (Miller and others, 1978).
Geologic map unit (-147.836736596572, 62.840740550226)
Mineral deposit model Porphyry Cu-Au? (Cox and Singer, 1986; model 20c?)
Mineral deposit model number 20c?
Alteration of deposit Local bleaching and iron staining (Kurtak and others, 1992).

Production and reserves

Workings or exploration Only surface sampling by the U.S. Bureau of Mines (Kurtak and others, 1992) and the U.S. Geological Survey (Miller and others, 1978).
Indication of production None

Additional comments

MAS/MILS number 20760113.

References