Nearhouse (and Smith)

Mine, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities Pb; Zn
Ore minerals arsenopyrite; galena; gold; pyrite; sphalerite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale D-7
Latitude 60.8658
Longitude -149.5198
Nearby scientific data Find additional scientific data near this location
Location and accuracy The mine is located in the SE1/4 section 18, T. 9 N., R. 1 W., of the Seward Meridian. It is at elevations between 2,800 and 3,100 feet, on the divide between Bear and Palmer Creeks. This is location 7 of Cobb and Richter (1972), location 6 of MacKevett and Holloway (1977), location 12 of Cobb and Tysdal (1980), and location S-299 of Jansons and others (1984). The location is accurate to within a quarter of a mile.

Geologic setting

Geologic description

The deposit at the Nearhouse mine consists of a banded and brecciated quartz vein averaging 20 inches wide. The banding is dark gray and is believed to be attributed to organic material. The vein strikes N50-80W and dips 60-90N. Metallic minerals include small amounts of arsenopyrite, galena, sphalerite, pyrite, and gold, which collectively make up less than one-half percent of the vein material. The vein is cut off at both ends by left-lateral transverse faults. However, the vein has good continuity at the surface and to a depth of more than 80 feet in the winze (Hoekzema and Sherman, 1983).
The host rock is well-bedded, slightly metamorphosed siltstone and sandstone (Hoekzema and Sherman, 1983) of the Valdez Group of Late Cretaceous age (Nelson and others, 1985). The beds strike N15E and dip 60W at the 3,100-foot adit level. Abundant sedimentary features at the portal suggest that the bedding is overturned (Mitchell, 1979). Felsic dikes crop out nearby, and one was intersected in the east drift of the 3,100-foot level adit.
Geologic map unit (-149.52197144773, 60.8652392995066)
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 cuts rocks of the Valdez Group of Late Cretaceous age.

Production and reserves

Workings or exploration
The workings at this mine consist of two adits: the upper adit, at 3,100 feet elevation, has 450 feet of workings plus an 80-foot winze; the lower adit, at an elevation of 3,050 feet, is 35 feet long (Jansons and others, 1984). In 1981, some old equipment at the site included a Worthington compressor. An old mine road leads to the workings from the Palmer Creek road.
Tuck (1933) visited the mine in 1931 and collected eight samples that assayed from 0.03 to 1.3 ounces of gold per ton and 0.3 to 3.5 ounces of silver per ton. The gold assays of the eight samples averaged 0.7 ounce per ton.
In 1980 and 1981, the U.S. Geological Survey and U.S. Bureau of Mines mapped and sampled the deposit (Hoekzema and Sherman, 1983). The Bureau collected six chip samples that assayed from a trace to 0.45 ounce of gold per ton and from 0.02 to 0.13 ounce of silver per ton. Reserves are estimated at 7,000 tons of ore containing 0.2 ounce of gold per ton and 0.3 ounce of silver per ton (Jansons and others, 1984).
Indication of production Yes; small
Reserve estimates Reserves are 7,000 tons of ore containing 0.2 ounce of gold per ton and 0.3 ounce of silver per ton (Jansons and others, 1984).
Production notes Recorded production is 102 ounces of gold and 3 ounces of silver (Jansons and others, 1984).

Additional comments

Hoekzema and Sherman (1983) reported dynamite and caps in the west drift of the 3,100 foot level. The explosives were destroyed by the Army Explosive Ordinance Disposal Unit in 1995 (C. S. Huber, oral communication, 2000).

References

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.
Mitchell, P.A., 1979, Geology of the Hope-Sunrise (gold) mining district, north-central Kenai Peninsula, Alaska: Stanford University Master of Science thesis, 123 p.
Reporters Jeff A. Huber (Anchorage)
Last report date 2/21/2000