Harris and Brown

Prospect, Inactive

Alternative names

Sky High
Grace E#1

Commodities and mineralogy

Main commodities Au
Other commodities Sb
Ore minerals arsenopyrite; gold; jamesonite; pyrite; stibnite; zinkenite

Geographic location

Quadrangle map, 1:250,000-scale LG
Quadrangle map, 1:63,360-scale A-1
Latitude 65.069
Longitude -147.379
Nearby scientific data Find additional scientific data near this location
Location and accuracy Cobb (1972, MF-413), loc. 44; SW1/4SE1/4 sec. 20, T. 3 N., R. 2 E., of the Fairbanks Meridian. This prospect is on the summit of the divide between Chatham and Wolf Creeks; it is at an elevation of 2,050 feet, between the two northernmost pinnacles of schist. Accuracy is within 1,000 feet.

Geologic setting

Geologic description

Mineralization consists of stibnite filling open fractures and a small proportion of sulfides (Smith, 1913; B 525). Minor amounts of jamesonite, arsenopyrite, pyrite and zinkenite(?) also were identified (Chapman and Foster, 1969). By 1912, a 60-foot-deep shaft had been sunk and 120 feet of drift had been driven at the 60-foot-level. Stoping of ore began in December, 1912. A 6- to 30-inch wide brecciated and quartz-cemented shear zone in the shaft trends N 70 E and dips 45 S (Times Publishing Company, 1912, p. 64). Assays from the development muck ranged from $28 to $130 per ton in gold (1.3 to 6.3 ounces of gold per ton) and average $30 per ton (1.4 ounces of gold per ton).
Cobb (1976, p. 80) noted that Grace E #1 is probably the same ground as Harris and Brown or Sky High. Forbes and others (1968) reported that the Grace E #1 prospect opened two small quartz veins that carry 2%-3% sulfides (including arsenopyrite and minor pyrite) and free-milling gold. An unaltered schist 9 feet into the hanging wall assayed 1.3 ppm gold.
Geologic map unit (-147.38144844218, 65.0685776343418)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c

Production and reserves

Workings or exploration By 1912, a 60-foot-deep shaft had been sunk and 120 feet of drift had been driven at the 60 foot level (Times Publishing Company, 1912, p. 64). Stoping of ore began in December, 1912.
Indication of production Yes; small

References

MRDS Number A015445

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.)
Times Publishing Company, 1912, Tanana Magazine, Quartz Edition: Fairbanks, Alaska, Times Publishing Company, 76 p.
Reporters C.J. Freeman, J.R. Guidetti Schaefer (Avalon Development Corporation)
Last report date 5/4/1999