Reinken, Bornite Lake

Prospect, Inactive

Commodities and mineralogy

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

Geographic location

Quadrangle map, 1:250,000-scale UN
Quadrangle map, 1:63,360-scale A-3
Latitude 53.4988
Longitude -166.9704
Nearby scientific data Find additional scientific data near this location
Location and accuracy Three kilometers south of the head of Pumicestone Bay in a lake basin; the lake is locally called Bornite Lake.

Geologic setting

Geologic description

Quartz veins up to 60 cm wide cut a silicified roche moutonnee immediately north of lake. Roche moutonnee is pervasively silicified and 500 feet wide by 1,500 feet long (150 x 450 m). Up to 30 percent pyrite occurs in veins and silicified rock. Country rock shown in Drewes and others (1961) as Unalaska Formation, about 2 km from mapped southern margin of Shaler batholith (granodiorite).
Geologic map unit (-166.972270502295, 53.4979352166701)
Mineral deposit model Polymetallic vein, epithermal gold vein
Mineral deposit model number 22c, 25
Age of mineralization Miocene or younger.
Alteration of deposit Pervasive silicification of country rocks.

Production and reserves

Workings or exploration Reported 18th or 19th century mining by Russians. No evidence remains of Russian activity; prospect possibly staked by John and Leon Reinken in 1929. Kennecott-Alaska (Simpson, 1986) collected 23 rock samples; Battle Mountain Exploration Co. (Randolph, 1991) collected pan concentrates and an additional 9 rock samples. None of BMEC rock samples were anomalous in gold; one contained 4.8 ppm silver, 9,085 ppm copper, and 410 ppb mercury. Pan concentrates contained up to 240 ppb gold and 920 ppm copper.
Indication of production None

Additional comments

Reportedly mined during Russian period, Battle Mountain Exploration Co. (Simpson, 1986; erroneously reported as the 1600s). Randolph (1991) gave the prospect a poor potential for economic gold mineralization due to remoteness, ruggedness of the environment, and minimal evidence for economic mineralization.

References

MRDS Number A106002

References

Randolph, D.B., 1991, Unalaska project, 1990 final report: Battle Mountain Exploration Company, Alaska District, 62 p., 5 appendices, 15 plates, various scales. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Simpson, D.F., 1986, Aleutian Islands project, 1985 final report: Kennecott Alaska Exploration Company, 54 p. (Report held by the Aleut Native Corporation, Anchorage, Alaska.)
Reporters F.H. Wilson
Last report date 12/18/1992