Mineral King

Mine, Inactive

Alternative names

Herman and Eaton
Bettles Bay
Herman-Everman
Merrill

Commodities and mineralogy

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

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale D-4
Latitude 60.9478
Longitude -148.3482
Nearby scientific data Find additional scientific data near this location
Location and accuracy The mine is located in the NW1/4 section 23, T. 10 N., R. 6 E. of the Seward Meridian, about 0.6 mile west-southwest of the head of Bettles Bay. Workings are located at 450 feet elevation and the mill is near sea level. This is location 124 of Condon and Cass (1958), location 68 of Cobb and Richter (1972), location 81 of MacKevett and Holloway (1977), 129 of Cobb and Tysdal (1980), and location S-156 of Jansons and others (1984). This location is accurate to within a quarter of a mile.

Geologic setting

Geologic description

The Mineral King mine is along the sheared contact between fine-grained dark-gray graywacke and argillite of the Valdez Group of Late Cretaceous age and a large Tertiary granitic dike (Nelson and others, 1985). The sedimentary strata strike N56E and dip NE. The dike strikes northeast, and the dip is nearly vertical (Hoekzema and Sherman, 1983). The deposit consists of quartz-cemented shattered country rock in a shear zone that strikes N26W and dips 45E. The deposit is traceable along strike for about 200 feet. The mineralized breccia, which fills the shear zone, is 2 to 6 feet wide and averages about 3 feet wide. The quartz contains arsenopyrite, sphalerite, chalcopyrite, galena, pyrite and gold (Johnson, 1914 [B 592-G, p. 231-232]).
There are 1,488 feet of underground workings, consisting of a tunnel and a 780-foot-long adit with stopes and winzes. The workings are 450 feet above sea level; a mill is near sea level. The adit provided haulage from the vein to the tramway that fed the mill.
A 16-inch-wide quartz vein is about 360 feet from the portal. The vein contains considerable shattered country rock along with calcite. The vein was stoped from the 450-foot level to the surface at 650 feet elevation. The length of the stope varies from 230 feet to less than 100 feet near the surface (Hoekzema and Sherman, 1983).
Geologic map unit (-148.350292147135, 60.9472220204409)
Mineral deposit model Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Tertiary or younger; the deposit is in a shear zone that cuts Cretaceous and Tertiary rocks.

Production and reserves

Workings or exploration
There are 1,488 feet of underground workings, consisting of a tunnel and a 780-foot-long adit with stopes and winzes The adit provided haulage from the vein to the 2,000-foot-long jig-back tram to the mill.
The vein was stoped from the 450 level to the surface at 650 feet elevation. The length of the stopes varies from 230 feet to less than 100 feet near the surface (Hoekzema and Sherman, 1983).
The mill consisted of a jaw crusher, two 1,350-pound stamps, a Wilfley concentrating table, and an 9 by 8 Ingersoll Rand air compressor. The compressor was driven by water taken from Eaton Creek (not named on the topographic map) under a head of 200 feet. A 7 by 6 compressor powered by a gas engine was situated at the portal for use when water was not available for the pelton-driven compressor (Pilgrim, 1933).
The U.S. Bureau of Mines collected nine grab and chip samples, which contained from a trace to 0.15 ounce of gold per ton and from 0.01 to 0.13 ounce of silver per ton (Hoekzema and Sherman, 1983). Hoekzema and Sherman (1983) speculated that the high-grade portions of the vein may have been mined out.
Indication of production Yes; small
Reserve estimates The U.S. Bureau of Mines estimates a resource of 500 tons of material with a grade of 0.012 ounce of gold per ton and as much as 5,000 tons of untested tailings (Hoekzema and Sherman, 1983).
Production notes The U.S. Bureau of Mines estimates that total production was 2,783 ounces of gold and 629 ounces of silver from 3,500 tons of ore (Hoekzema and Sherman, 1983).

Additional comments

The mine is adjacent to a state marine park.

References

MRDS Number A010403

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.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1915: U.S. Bureau of Mines Bulletin 142, 65 p.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1916: U.S. Bureau of Mines Bulletin 153, 89 p.
Reporters Jeff A. Huber (Anchorage)
Last report date 9/7/2000