Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities As; Bi; Cd; Cu; Hg; Pb; Sb; W
Ore minerals scheelite; unspecified sulfides
Gangue minerals axinite; quartz; tourmaline

Geographic location

Quadrangle map, 1:250,000-scale SM
Quadrangle map, 1:63,360-scale D-7
Latitude 61.75383
Longitude -158.48451
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is in a saddle of the divide that separates the head of Whitwing Creek to the south from the head of Getmuna Creek on the north. The prospect is at an elevation of about 3,000 feet in the NW1/4 sec. 11, T. 19 N., R. 51 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description

At the Saddle prospect, a syenite-hosted, conjugate set of veins contains axinite, quartz, tourmaline and unspecified, largely oxidized sulfides. The veins range from 1 to 6 inches thick; they dip steeply and strike N60E and N20W. The overall zone trends N20W, parallel to the faulted contact between several phases of the Horn Mountains pluton (Bundtzen and others, 1998). The veins contain 2 to 25 percent tourmaline and axinite, and 1 to 2 percent, fine grained, gray sulfides. The total width of the mineralized zone is estimated to be about 50 feet. Chip samples 3 to 5 feet wide contained up to 514 parts per billion (ppb) gold, 18,900 ppb silver, 642 parts per million (ppm) arsenic, 4.0 ppm cadmium, 48 ppm antimony, 7.0 ppm bismuth, and 14.3 ppm mercury (Bundtzen and others, 1998).
The Saddle prospect is in an area of anomalous stream sediment and panned concentrate samples (Gray and others, 1994; Theodorakos and others, 1992). Stream sediment samples contained up to 700 ppb gold, 680 ppb silver, 120 ppm copper, 370 ppm arsenic, 35 ppm antimony, and other elevated metal values. Panned concentrates contained up to 30.0 ppm gold, 15.0 ppm silver, 2,000 ppm lead, 300 ppm antimony, 1,000 ppm bismuth, and 700 ppm tungsten; several samples contained microscopically visible gold, scheelite, and barite.
Geologic map unit (-158.486887367925, 61.7531249973872)
Mineral deposit model Sn-polymetallic veins or tin veins (Cox and Singer, 1986; models 20b or 15b).
Mineral deposit model number 20b or 15b
Age of mineralization Undated; may be related to the nearby Horn Mountain pluton which has been dated at 68-69 Ma (Bundtzen and others, 1998).
Alteration of deposit Axinite-tourmaline-sulfide greisen.

Production and reserves

Workings or exploration Surface sampling was conducted by the Alaska Division of Geological and Geophysical Surveys in 1990 (Bundtzen and others, 1998).
Indication of production None

Additional comments

Is also known as the 'Whitewing' prospect (Morris Hofseth, oral communication, 1990)