Emma

Mine, Inactive

Alternative names

Overgard
Kathrine

Commodities and mineralogy

Main commodities Au
Other commodities Sb; Zn
Ore minerals arsenopyrite; gold; pyrite; sphalerite; stibnite

Geographic location

Quadrangle map, 1:250,000-scale LG
Quadrangle map, 1:63,360-scale A-1
Latitude 65.051
Longitude -147.444
Nearby scientific data Find additional scientific data near this location
Location and accuracy Cobb (1972, MF-413), loc. 35; NE1/4 sec. 36, T. 3 N., R 1 E., of the Fairbanks Meridian. This mine is on the east side of Willow Creek, near its head, at an elevation of 2,100 feet; it is about 1/4 mile northwest of Cleary Summit along the Steese Highway. Accuracy is within 1,000 feet.

Geologic setting

Geologic description

By 1909, a 40 foot shaft had been sunk on the prospect and a northeast striking, steeply southeast dipping quartz-bearing shear zone was exposed. The higher grade portion of the shear was 2 to 16 inches wide and contained gold, stibnite, arsenopyrite, pyrite and minor sphalerite (Prindle, 1910). The schist host rock is strongly brecciated and cemented by quartz. By 1912, the shaft had been sunk to a depth of 60 feet with short drifts at the 60-foot level (Smith, 1913; B 525). The shear is hosted in part by mafic metavolcanic rocks and exhibits considerable offset by faulting. The shear dips steeply to the south at the surface but flattens to 45 degrees at depth. Ten tons of ore from this prospect were milled in Fairbanks and contained $38 per ton in gold (1.8 ounces of gold per ton). Chapin (1914) reported that in 1913 the drifts at the 60-foot level were 30 feet and 70 feet long to the east and west, respectively. An adit was being driven from the Willow Creek basin to allow exploration and development to proceed. A minor amount of exploration was completed on the prospect in 1914 (Eakin, 1915). A small amount of production was recorded from the prospect in 1917 however no tonnage or grade information is available (Martin, 1919). The prospect was idle until 1924 when it was re-opened, however, it was abandoned shortly afterwards and was idle when visited in 1931 (Hill, 1933).
Geologic map unit (-147.446446277253, 65.0505765342882)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c

Production and reserves

Workings or exploration By 1910, the vein was exposed by a 40 foot shaft (Prindle, 1910). Chapin (1914) reported a 60 foot inclined shaft and 100 feet of drifts.
Indication of production Yes; small
Production notes Ten tons of ore from this prospect were milled in Fairbanks and contained $38 per ton in gold (1.8 ounces of gold per ton) (Smith, 1913; B 525). A small amount of production was recorded from the prospect in 1917 however no tonnage or grade information is available (Martin, 1919).

References

MRDS Number A015396

References

Freeman, C.J., 1992, 1991 Golden Summit project final report, volume 2: Historical summary of lode mines and prospects in the Golden Summit project area, Alaska: Avalon Development Corp., 159 p. (Report held by Freegold Recovery Inc. USA, Vancouver, British Columbia.)
Reporters C.J. Freeman, J.R. Guidetti Schaefer (Avalon Development Corporation)
Last report date 5/4/1999