North Star

Prospect, Inactive

Alternative names

Skoogy Gulch
Big Lead

Commodities and mineralogy

Main commodities Au
Other commodities Sb
Ore minerals arsenopyrite; gold; stibnite

Geographic location

Quadrangle map, 1:250,000-scale LG
Quadrangle map, 1:63,360-scale A-1
Latitude 65.033
Longitude -147.47
Nearby scientific data Find additional scientific data near this location
Location and accuracy Cobb (1972, MF-413), loc. 30; NW1/4 sec. 1, T. 2 N., R. 1 E., of the Fairbanks Meridian. This prospect is in the lower part of Skoogy Gulch about 1/4 mile north of confluence with Twin Creek; it is about 7.5 miles northeast of Fox along the Steese Highway. The location given is on the workings exposing the Big Lead vein. There are also open cuts and a shallow shaft above a tunnel that runs westward from Skoogy Gulch under the highway. Accuracy is within 1,000 feet.

Geologic setting

Geologic description

This prospect consists of gold-bearing quartz veins in heavily silicified schist. Hill (1933, p. 116-117) visited the area in 1931 and described the prospect: A shallow shaft was driven on a vein trending N 84 W and dipping 85 S, which yielded ore valued at $5,000. As exposed in the tunnel, this vein is from 1 to 4 inches wide and consists of white quartz frozen to a dark, heavily silicified schist. Some of the quartz carries minor sulfides, but in general it has no visible metallic mineralization. This vein cuts across a lenticular mass of quartz lying parallel to the schistosity, which dips 15 SE. A 30-inch aplite dike that strikes north and dips 15 E is also cut by this vein. In open cuts, the vein was observed to be 3 to 6 inches wide and in places lies along the contact of schist and porphyritic granite. About 140 feet north of this vein, another 5-inch quartz vein in schist was said to have produced a ton of $35 ore (1.69 ounces of gold per ton).
When Hill (1933) visited the site in 1931, the Big Lead vein was exposed along an old wagon road on the east side of Skoogy Gulch just south of a cabin. Several feet of tunnels were driven on this vein and an engineer that visited the site estimated that the whole ore body exposed in these tunnels would average about $4 per ton (0.19 ounces of gold per ton). The tunnels were caved by 1931, but the material on the dump consisited of heavily iron-stained mineralized schist and quartzite. One dump site contained boulders dominated by arsenopyrite and stibnite. There is evidence of silicification and mineralization over a width of 75.5 feet. The mineralized zone shows an alternation of schist, altered dike rocks, quartz veinlets, and faults. A sample of granular, highly altered, brick-red dike rock containing irregular veinlets and bunches of manganese-oxide; it assayed $0.43 per ton (0.02 ounces of gold per ton).
Geologic map unit (-147.472444110875, 65.0325760111267)
Mineral deposit model Gold-quartz veins.
Alteration of deposit Schist iron-stained.

Production and reserves

Workings or exploration Several feet of tunnels and shallow shafts (Hill, 1933).
Indication of production Undetermined

References

MRDS Number A015382

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