Unnamed (northeast of peak 7360) (ARDF #MH257) Ag, Pb, Sb, Zn

Unnamed (northeast of peak 7360)

Occurrence, Probably inactive

Commodities and mineralogy

Main commodities	Ag; Pb; Sb; Zn
Other commodities	As; Au
Ore minerals	arsenopyrite; chalcopyrite; galena; pyrite; pyrrhotite; sphalerite; stibnite
Gangue minerals	adularia; calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	MH
Quadrangle map, 1:63,360-scale	B-2
Latitude	63.3046
Longitude	-144.6034
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is near the peak at the head of Snowslide Creek and at an elevation of about 7,400 feet. It is about 0.6 mile south-southeast of the center of section 36, T. 18 S., R. 16 E., Fairbanks Meridian. The location is accurate.

Geologic setting

Geologic description This occurrence is part of a northwest-trending set of structurally controlled sulfide veins and veinlets that are intermittently exposed for about 9 miles between the Robertson Glacier and the glacier at the head of the West Fork Robertson River. Coarse-grained pyrite, arsenopyrite, galena, sphalerite, and stibnite occur in a gangue of quartz and carbonate with patches of adularia (?). The veins crosscut both bedding and schistosity but are locally parallel to them. The rocks in this area are siliceous metasedimentary rocks that include quartzite, quartz arenite, and siliceous siltstones (R.A. Blakestad and others, unpublished Resource Associates of Alaska, Inc. report, 1978). Samples contain as much as 1.5 percent lead, 9 percent zinc, 5 to 9 ounces of silver per ton, 0.9 part per million gold, and no copper (R.A. Blakestad and others, unpublished Resource Associates of Alaska, Inc. report, 1976). Geologic mapping and geochemical sampling was done from 1976 to 1979; however, most of the work in this area was concentrated on similar veins nearby, such as the RC East prospect (MH255).
Geologic map unit	(-144.605645560296, 63.3042175539682)
Mineral deposit model	Polymetallic veins (Cox and Singer, 1986; model 22c).
Mineral deposit model number	22c
Age of mineralization	Devonian or younger, on the basis of the age of the host rock, which is in the Jarvis Creek Glacier subterrane (Nokleberg and others, 1992).

Production and reserves

Workings or exploration	Geologic mapping and geochemical sampling was done from 1976 to 1979; however, most of the work in this area was concentrated on similar deposits nearby.
Indication of production	None
Additional comments Unpublished data cited is available for viewing by contacting Grayd Resources Inc. in Vancouver, B. C., Canada (www.grayd.com), or Northern Associates Inc. in Fairbanks, Alaska.

References

References Nokleberg, W.J., Aleinikoff, J.N., Lange, I.M., Silva, S.R., Miyaoka, R.T., Schwab, C.E., Zehner, R.E., Bond, G.C., Richter, D.H., Smith, T.E., and Stout, J.H., 1992, Preliminary geologic map of the Mount Hayes quadrangle, eastern Alaska Range, Alaska: U.S. Geological Survey Open-File Report 92-594, 39 p., 1 sheet, scale 1:250,000.
Reporters	W.T. Ellis (Alaska Earth Sciences) and A.W. Wyatt and S.S. Dashevsky (Northern Associates Inc.)
Last report date	3/20/2003