Swan

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities As
Ore minerals gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale PM
Quadrangle map, 1:63,360-scale B-3
Latitude 55.258
Longitude -160.744
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is located on Unga Island approximately 4 miles southwest of the head of Zachary Bay. The map site is at an elevation of about 200 feet, on a creek in the SE1/4 of sec. 12, T. 57 S., R. 76 W., Seward Meridian. The location is accurate to within 2,500 feet.

Geologic setting

Geologic description

This occurrence consists of a 1100- by 600-foot area containing scattered quartz veins in argillically and locally propylitically altered tuff (Ellis, 1988). The volcanic rock is Tertiary in age (Wilson and others, 1995). Chalcedonic quartz occurs in veins 0.5 to 6 inches wide containing up to 5 percent disseminated pyrite and scattered pyrite boxworks. Rock samples were anomalous in arsenic, but only a trace gold was detected. Pan samples contained as much as 0.36 ppm gold (Ellis, 1988).
Geologic map unit (-160.746048892406, 55.2571652979862)
Mineral deposit model Epithermal gold veins
Age of mineralization Tertiary.
Alteration of deposit The host rocks are weakly to moderately argillized; there are some patches of propylitization.

Production and reserves

Workings or exploration Battle Mountain Exploration Company examined the area in 1988 and collected 21 rock samples for analysis. The samples were anomalous in arsenic, but contained only a trace of gold. Pan samples contained as much as 0.36 ppm gold (Ellis, 1988).
Indication of production None

Additional comments

This prospect is located on land patented by, or interim-conveyed to, the Aleut Corporation.

References

References

Ellis, W.T., 1988, Unga/Alaska Peninsula project, 1988 report: Battle Mountain Exploration Company report, 64 p. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Reporters S.H. Pilcher
Last report date 2/4/2001