Unnamed (east of Specimen Creek)

Occurrence, Active

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; marcasite; pyrite; pyrrhotite
Gangue minerals garnet; pyroxene

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-5
Latitude 63.299
Longitude -146.0082
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 5,200 feet on an east-west-trending ridge east of Specimen Creek, in the SW1/4NW1/4 section 3, T. 19 S., R. 9 E., Fairbanks Meridian. This occurrence corresponds to locality 10 on figure 2 of Rose (1965), locality 43 on figure 4 of Cobb (1979 [OFR 79-238), and locality 63 in table 2 of Nokleberg and others (1991).

Geologic setting

Geologic description

The rocks in the area of this occurrence consist of a limestone mass of the Slana Spur Formation of Late Paleozoic age engulfed in mafic-ultramafic intrusive rock of the Upper Triassic Eureka complex. The rocks at this deposit consist of sulfide-bearing skarn composed chiefly of brown garnet and greenish pyroxene, highly pyritized limestone (?) that overlies the skarns, and a capping sequence of nearly unaltered limestone. Float collected below the skarn contains pyrite and pyrrhotite and lesser amounts of chalcopyrite and marcasite (Rose, 1965).
Geologic map unit (-146.010460570628, 63.2985806146083)
Mineral deposit model Skarn affiliated with mafic-ultramafic intrusive rocks.
Age of mineralization Late Triassic, the age of the mafic-ultramafic intrusive rocks.
Alteration of deposit Sulfide minerals are disseminated in a matrix of brown garnet and greenish pyroxene skarn. Limestone overlying the skarn is pyritized.

Production and reserves

Workings or exploration The occurrence is on active MAN Resources claims.
Indication of production None