Unnamed (west of upper Indian River)

Occurrence, Probably inactive

Commodities and mineralogy

Main commodities Cr; Fe; Ni
Ore minerals chromite; magnetite
Gangue minerals serpentine

Geographic location

Quadrangle map, 1:250,000-scale SI
Quadrangle map, 1:63,360-scale A-4
Latitude 57.0999
Longitude -135.3005
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 2,400 feet on the ridge west of upper Indian River, about 0.8 mile northeast of hill 2505. The occurrence is 0.1 mile southwest of the center of sec. 18, T. 55 S., R.64 E. It is location P-111 of Bittenbender and others (1999); location 53 of Cobb (1972, 1978); and MAS no. 0021140001 (U.S. Bureau of Land Management, 2002). The location is accurate within 0.5 mile.

Geologic setting

Geologic description

This occurrence consists of magnetite and chromite in serpentine. Loney and others (1963, 1975) map this small Mesozoic serpentinite body (sliver?) in rocks of the Jurassic and Triassic, Kelp Bay Group which consists of phyllite, greenschist, greenstone, graywacke, and semischist that has been cataclastically deformed. There is no indication that the magnetite and chromite are other than normal trace minerals in the serpentine. Spectrographic analysis indicates a small amount of nickel in the samples but probably no more than the expected level of background in serpentine.
Geologic map unit (-135.302261265417, 57.0995387297852)
Mineral deposit model Minor magnetite and chromite in serpentine.
Age of mineralization The magnetite and chromite was probably contemporaneous with the solidification of the ultramafic rock that was altered to serpentine in the Mesozoic.

Production and reserves

Workings or exploration Only surface sampling.
Indication of production None