Sunshine

Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities Cu
Ore minerals chalcopyrite; gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale D-7
Latitude 60.8099
Longitude -149.5567
Nearby scientific data Find additional scientific data near this location
Location and accuracy The prospect is located in the SW1/4 section 1, T. 8 N., R. 2 W., of the Seward Meridian. It is situated 500 to 1,500 feet west of the Palmer Creek road, at an elevation of 2,050 to 3,050 feet. It is mislocated on the Seward D-7 topographic map. This is location 10 of Cobb and Richter (1972), location 9 of MacKevett and Holloway (1977), location 21 of Cobb and Tysdal (1980), and location S-293 of Jansons and others (1984). The location is accurate to within 300 feet.

Geologic setting

Geologic description

The deposit at the prospect consists of two principal quartz veins and some small seams of quartz. The veins are in massive graywacke of the Valdez Group of Late Cretaceous age that is cut by several thrust faults (Tuck, 1933; Nelson and others, 1985). The thrust faults are located about 40 feet from the portal at the 2,700-foot level, trend N20E, and dip 15-30W. The faults contain from 2 to 8 inches of gouge in which there are small seams of quartz that carry visible gold. The vein that has received the most attention is at an elevation of 2,700 feet. It ranges from 6 to 12 inches wide, strikes generally east-west, and dips almost vertically. The other vein is 2 to 12 inches wide, horizontal, and intersects the first vein at the 2,700-adit level. Both veins have very tight walls and appear to be localized by originally small fractures along which quartz-bearing solutions replaced the country rock. The replacement is irregular; in places the veins lose their planar form, and the quartz occurs in irregular masses (Tuck, 1933). Both veins carry small amounts of chalcopyrite, pyrite, and gold.
Geologic map unit (-149.558863386021, 60.8093276609431)
Mineral deposit model Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Cretaceous or younger; the veins cut rocks of the Valdez Group of Late Cretaceous age.

Production and reserves

Workings or exploration
Tuck (1933) reported one 130-foot adit at an elevation of 2,700 feet. The U.S. Bureau of Mines reported three adits, at elevations of 2,050, 2,700, and 3,050 feet (Jansons and others, 1984). The lower level is caved at the portal, the middle level is reported to be 300 feet long and is caved 75 feet from the portal, and the upper level is accessible and 130 feet long. There are several prospect pits nearby.
The U.S. Bureau of Mines examined the prospect in 1980 and collected two grab samples and four chip samples. The grab samples assayed trace amounts of gold and a trace to 0.01 ounce of silver per ton. Four chip samples from the 130-foot-long adit assayed from nil to 0.73 ounce of gold per ton and nil to 0.3 ounce of silver per ton (Jansons and other, 1984).
Indication of production None
Reserve estimates The U.S. Bureau of Mines estimated 350 tons at 0.1 ounce of gold per ton (Jansons and others, 1984).
Production notes An unpublished report of the U.S. Bureau of Mines, date unknown, referenced in Hoekzema and Sherman (1983) reported 347 ounces of gold, but Jansons and others (1984) indicated no production. It is likely that the published report is the accurate one.

References

MRDS Number A010550

References

Hoekzema, R.P., and Sherman, G.E., 1983, Mineral investigations in the Chugach National Forest, Alaska (Peninsula study area): U.S. Bureau of Mines in-house report; held at U.S. Bureau of Land Management Alaska State Office, Anchorage, 524 p.
Mitchell, P.A., 1979, Geology of the Hope-Sunrise (gold) mining district, north-central Kenai Peninsula, Alaska: Stanford University Master of Science thesis, 123 p.
Reporters Jeff A. Huber (Anchorage)
Last report date 2/19/2000