Unnamed (in the Helpmejack Hills)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Mn
Ore minerals manganite; pyrolusite; rhodochrosite

Geographic location

Quadrangle map, 1:250,000-scale HU
Quadrangle map, 1:63,360-scale D-2
Latitude 66.998
Longitude -153.8829
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is north of the Helpmejack Hills, about 10 miles west-northwest of Helpmejack Lakes and about 18 miles northeast of Norutak Lake. It is at an elevation of about 3,400 feet in the SW 1/4 of section 32, T. 19 N., R. 23 E., of the Kateel River Meridian. The location is accurate within 1 mile.

Geologic setting

Geologic description

Rhodochrosite, manganite, and pyrolusite occur in Devonian(?) altered mafic volcanic rocks and phyllite (Patton and Miller, 1966). Field investigators in the 1990s were not able to locate the occurrence (Kurtak and others, 2002). No other information is available.
Geologic map unit (-153.885628838766, 66.9975011408831)
Mineral deposit model Volcanogenic Mn? (Cox and Singer, 1986; model 24c?).
Mineral deposit model number 24c?

Production and reserves

Indication of production None

References

MRDS Number A015580

References

Bottge, R.G., 1988, Maps summarizing land availability for mineral exploration and development in western Alaska, 1986: U.S. Bureau of Mines Open-File Report 14-88, 38 quadrangle overlays.
Kurtak, J.M., Klieforth, R.F., Clark, J.M., and Maclean, E.A., 2002, Mineral investigations in the Koyukuk mining district, northern Alaska: Final Report: U.S. Bureau of Land Management Technical Report 50, v. 1 and 2, 845 p.
Reporters J.M. Britton (Anchorage)
Last report date 8/1/2002