Prospect, Inactive

Alternative names

Yakima Ledge

Commodities and mineralogy

Main commodities Au
Other commodities Cu; Pb; Zn
Ore minerals arsenopyrite; chalcopyrite; galena; gold; pyrite; pyrrhotite; sphalerite
Gangue minerals calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale D-4
Latitude 60.9627
Longitude -148.3122
Nearby scientific data Find additional scientific data near this location
Location and accuracy The prospect is at or near sea level near the head of Bettles Bay. It is in the N1/2 section 13, T. 10 N., R. 6 E., of the Seward Meridian. This is location 121 of Condon and Cass (1958), location 69 of Cobb and Richter (1972), location 82 of MacKevett and Holloway (1977), location 128 of Cobb and Tysdal (1980), and location S-151 of Jansons and others (1984). This location is accurate to within half a mile.

Geologic setting

Geologic description

The Yakima Ledge prospect consists of a 10- to 31-inch-wide banded quartz-calcite vein that strikes N12E and dips 80W. The vein occurs in a shear zone and contains quartz, calcite, arsenopyrite, chalcopyrite, galena, pyrite, pyrrhotite, sphalerite, and gold (Johnson, 1914 [B 592-G, p. 231]). The host rock is graywacke and slate of the Upper Cretaceous Valdez Group (Cobb and Tysdal, 1980).
Workings on the prospect consist of a 65-foot adit (Johnson, 1914 [B 592-G, p. 231]). No assay results are reported.
Geologic map unit (-148.314287619188, 60.9621238289027)
Mineral deposit model Low-sulfide Au-quartz vein (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Cretaceous or younger; the vein is in a shear zone that cuts rock of the Valdez Group of Late Cretaceous age.

Production and reserves

Workings or exploration Workings on the prospect consist of a 65-foot adit (Johnson, 1914 [B 592-G, p. 231]). No assay results are reported. The U.S. Bureau of Mines searched for the prospect in 1980 but did not locate it.
Indication of production None


MRDS Number A010561


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.
Reporters Jeff A. Huber (Anchorage)
Last report date 1/21/2000