Unnamed (east of the toe of McCallum Glacier) (ARDF #MH236) Ag, Cu

Unnamed (east of the toe of McCallum Glacier)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Ag; Cu
Ore minerals	chalcopyrite; galena
Gangue minerals	quartz

Geographic location

Quadrangle map, 1:250,000-scale	MH
Quadrangle map, 1:63,360-scale	B-4
Latitude	63.2845
Longitude	-145.566
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is at an elevation of 6,200 feet approximately 1 mile east of the toe of McCallum Glacier. It is in the SW1/4NW1/4 section 12, T. 19 S., R. 11 E., Fairbanks Meridian. The occurrence is described by Hanson (1963, locality 13), and it corresponds to locality 27 in Cobb (1979 [OFR 79-238]) and locality S118 in table 2 of Nokelberg and others (1991).

Geologic setting

Geologic description This occurrence consists of chalcopyrite and galena in quartz veins as much as 6 inches thick that strike N60E and dip 40S (Hanson, 1963). The veins cut altered meta-andesite intruded by quartz diorite. A grab sample of iron-stained meta-andesite contained 3 parts per million silver (Nokleberg and others, 1991). The host rocks are part of the Slana Spur Formation of Pennsylvanian age (Nokleberg and others, 1991). This occurrence is one of the four prominent areas of pyrite and chalcopyrite disseminated in dacitic tuff noted by Hanson (1963, p. 67, figure 5).
Geologic map unit	(-145.568244137515, 63.2840885170283)
Mineral deposit model	Polymetallic veins (Cox and Singer, 1986; model 22c).
Mineral deposit model number	22c
Age of mineralization	Pennsylvanian or younger.
Alteration of deposit	The meta-andesite is highly altered adjacent to the quartz diorite intrusion (Hanson, 1963).

Production and reserves

Workings or exploration	A grab sample of iron-stained meta-andesite contained 3 parts per million silver (Nokleberg and others, 1991).
Indication of production	None

References

References Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount Hayes quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-238, 140 p. Hanson, L.G., 1963, Bedrock geology of the Rainbow Mountain area, Alaska Range, Alaska: Alaska Division of Mines and Minerals Geologic Report 2, 82 p., 2 plates. MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000. Nokleberg, W.J., Lange, I.M., Roback, R.C., Yeend, Warren, and Silva, S.R., 1991, Map showing locations of metalliferous lode and placer mineral occurrences, mineral deposits, prospects, and mines, Mount Hayes quadrangle, eastern Alaska Range, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1996-C, 42 p., 1 sheet, scale 1:250,000.
Reporters	W.T. Ellis (Alaska Earth Science), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)
Last report date	8/9/2002