Unnamed (ridge between Madison and Crevice Creeks) (ARDF #WI062) Cr, Ni

Unnamed (ridge between Madison and Crevice Creeks)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Cr; Ni
Other commodities	Pb; Zn
Ore minerals	arsenopyrite; sphalerite

Geographic location

Quadrangle map, 1:250,000-scale	WI
Quadrangle map, 1:63,360-scale	B-4
Latitude	67.3507
Longitude	-151.6897
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is on a ridge between Crevice Creek and Madison Creek at an elevation of 3900 feet, near the center of section 12, T. 29 N., R. 19 W., of the Fairbanks Meridian. This is the site of sample 71 in Dillon and others (1981 [AOF 133B]). The location is accurate.

Geologic setting

Geologic description This occurrence consists of a fuchsite-muscovite-calcite quartzite (Dillon and others, 1981 [AOF 133B]) in Middle or Upper Devonian(?), chloritic and carbonate rocks (Dillon and others, 1986). A grab sample contains 1000 ppm chromium, (probably attributable to the fuchsite) and 200 ppm nickel, as well as 500 ppm arsenic, and 200 ppm lead. The analytical data suggest that sphalerite and arsenopyrite might be present but neither was visible in the sample.
Geologic map unit	(-151.692438845158, 67.3502419808374)

Geologic description

This occurrence consists of a fuchsite-muscovite-calcite quartzite (Dillon and others, 1981 [AOF 133B]) in Middle or Upper Devonian(?), chloritic and carbonate rocks (Dillon and others, 1986). A grab sample contains 1000 ppm chromium, (probably attributable to the fuchsite) and 200 ppm nickel, as well as 500 ppm arsenic, and 200 ppm lead. The analytical data suggest that sphalerite and arsenopyrite might be present but neither was visible in the sample.

Geologic map unit

(-151.692438845158, 67.3502419808374)

Production and reserves

Workings or exploration	Only surface sampling.
Indication of production	None

References

MRDS Number	A011968
References Dillon, J.T., Cathrall, J.B., and Moorman, M.A., 1981, Geochemical reconnaissance of the southwest Wiseman quadrangle-summary of data on rock samples: Alaska Division of Geological and Geophysical Surveys Open-File Report 133B, 164 p.
Reporters	J.M. Britton (Anchorage)
Last report date	8/9/2002