Excelsior

Prospect, Inactive

Alternative names

Cross Vein

Commodities and mineralogy

Main commodities Au
Other commodities Ag; Pb; Sb
Ore minerals arsenopyrite; galena; gold; limonite; silver; stibnite

Geographic location

Quadrangle map, 1:250,000-scale LG
Quadrangle map, 1:63,360-scale A-1
Latitude 65.071
Longitude -147.315
Nearby scientific data Find additional scientific data near this location
Location and accuracy Cobb (1972, MF-413), loc. 49; SW1/4NE1/4 sec. 22, T. 3 N., R. 2 E., of the Fairbanks Meridian. This prospect is near the head of Too Much Gold Creek, a tributary to upper Fairbanks Creek, at an elevation of 1,625 feet. Accuracy is within 1,000 feet.

Geologic setting

Geologic description

By 1911, several prospect pits were reported along a 7-foot-wide mineralized zone containing $10 to $20 gold per ton (0.5 to 0.9 ounces of gold per ton) and $15 to $30 silver per ton (30 to 60 ounces of silver per ton, Brooks, 1911). A second shear contained chiefly galena with about $5 gold per ton (0.25 ounces of gold per ton). An unspecified amount of ore from the Excelsior prospect was custom milled in Fairbanks by 1911; however, production figures are not available.
By 1912, a southern adit 70 feet long and a northern adit 60 feet long had been driven. Both adits are located on the right-limit wall of Too Much Gold Creek. The shear averages 12 feet wide in the adits, and trends east-west with a steep south dip (Times Publishing Company, 1912; Smith, 1913; B 525). The ore in the adit contained 22 ounces of silver per ton. In the 70 foot adit, a drift had been turned off to the south on a crosscutting shear zone. The country rock in both adits consists of hard quartzite with lesser black carbonaceous schist (Smith, 1913; B 525). High silver grades in the northern adit are in carbonaceous schist that contains minor galena, arsenopyrite and stibnite. Above the Excelsior adits, exposures of fine grained quartz porphyry granite appear to be related to the mineralization in the Excelsior adits. This rock contains small cavities surrounded by limonite after sulfides. Although iron staining is pervasive in this rock, no metallic minerals were noted (Smith, 1913; B 525).
The Excelsior prospect was examined in 1916 to determine if commercial quantities of antimony existed; however, insufficient quantities were found to warrant exploration and development (Brooks, 1916; B 649). The Excelsior prospect was again examined in 1942 to determine if commercial quantities of antimony existed, however insufficient quantities were found to warrant exploration and development (Killeen and Mertie, 1951).
Geologic map unit (-147.317448079465, 65.0705790731875)
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 southern adit 70 feet long and a northern adit 60 feet long had been driven. Both adits are located on the right limit wall of Too Much Gold Creek. In the 70 foot adit, a drift was driven to the south on a crosscutting shear zone (Smith, 1913; B 525).
Indication of production Undetermined
Production notes An unspecified amount of ore from the Excelsior prospect was custom milled in Fairbanks by 1911; however, production figures are not available (Brooks, 1911).

References

MRDS Number A015458

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