Unnamed (near Siwash Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cr; Cu; Ni
Other commodities Ni
Ore minerals azurite; copper sulfides; magnetite; malachite

Geographic location

Quadrangle map, 1:250,000-scale CH
Quadrangle map, 1:63,360-scale A-6
Latitude 67.1333
Longitude -149.6435
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 3,000 feet, about 2.4 mile west of the junction of Siwash Creek and Mosquito Fork. It is about 0.2 mile southeast of the center of section 25, T. 27 N., R. 10 W.

Geologic setting

Geologic description

This occurrence was originally described as copper sulfides and copper staining at the contact between Devonian(?) black phyllite and slate and Devonian(?) pyroxene diorite and andesite flows (Brosgé and Reiser, 1964). Kurtak and others (2002) indicated that the diorite and andesite flows may be part of a 1,000-foot-wide band of mafic-ultramafic rocks bounded on both sides by chlorite-quartz schist. The mafic-ultramafic rock contains magnetite, is serpentinized at the margins of the band, and may be dunite. Samples of the serpentinized rock averaged 977 parts per million (ppm) nickel and 1,078 ppm chromite.
Geologic map unit (-149.64621013752, 67.1328766098691)
Mineral deposit model Insufficient information to assign.
Age of mineralization Insufficient information to assign.

Production and reserves

Workings or exploration Only limited sampling by government agencies.
Indication of production None
Reserve estimates None.
Production notes None.

Additional comments

MAS No. 0020310085