Ebbert

Mine, Active

Commodities and mineralogy

Main commodities Au
Other commodities Ag; As; Pb; Sb; Sn
Ore minerals arsenopyrite; galena; gold; jamesonite; stibnite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale LG
Quadrangle map, 1:63,360-scale A-1
Latitude 65.0666
Longitude -147.3613
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Ebbert prospect is in upper Wolf Creek approximately 2,000 feet northwest of the McCarty mine (LG152); it is in the SE1/4SW1/4 section 21, T. 3 N., R. 2 E., of the Fairbanks Meridian.

Geologic setting

Geologic description

Note: As of 2008, this site and several others in the vicinity are being explored as a single entity by Freegold Ventures Inc. (Freeman, 2008) Considerable new mineralization has been discovered that indicates this is part of a larger mineralized system that is described as a separate ARDF site (LG206).
The first work on the Ebberts Mine was done by Hugh M. Hinton, who hand trenched the prospect (Saunders, 1960). The prospect was inactive until about 1950 when it was dozer trenched by United States Smelting Refining and Mining (USSR&M). Initially the exploration was for antimony. In June 1960, Arctic Alaska Fisheries and Enterprises Inc. cut several dozer trenches on the prospect and exposed the Ebberts shear zone which is sometimes referred to as the Jamesonite shear zone (Saunders, 1960). The Ebbert deposit was mined for antimony from a shallow shaft and in open cuts from 1961 through 1964 by Ed Ebbert (R. Vetter, oral communication, 1986). The mine was idle until 1967 when Ed Ebbert reopened the shaft and trenches after finding high gold values in quartz-rich portions of the shear zone. In 1969, the Ebberts Mine was sampled by International Minerals and Chemicals (IMC) in the vicinity of the main shaft (Pilkington, 1970). IMC also excavated a dozer trench which crossed the Ebberts shear 200 feet east of the Ebberts shaft.
The deposit consists of gold-quartz-rich portions of a shear zone. The lode was sampled and mapped in 1968; it contained extremely high gold, silver, lead, antimony, arsenic and tin values (Forbes and others, 1968). The quartz veins and wall rock in old prospect trenches carry as much as 2.87 parts per million (ppm) gold (Pilkington and others, 1969). The veins predominantly trend in two directions: about N70W with a dip of 55S, and about N65E with a dip of 70S. Altered schist that extends as much as 1 foot into the footwall of the veins contain significant gold. Grab samples of the veins contained 0.05 and 2.87 ppm Au (Pilkington and others, 1969). In 1969, the Ebberts Mine was sampled by International Minerals and Chemicals (IMC) in the vicinity of the main shaft. Here the, the shear zone trends N85W and dips 60S; it consists of narrow quartz stockwork zones on the hanging wall and foot wall, separated by altered schist. Stibnite and jamesonite occur on the hanging wall and in kidney shaped masses. The mineralized zone is 13 feet wide and averaged 0.06 ounce of gold per ton and 8.4 ounces of silver per ton (Pilkington, 1970). IMC also excavated a dozer trench which crossed the Ebberts shear 200 feet east of the Ebberts shaft. Samples from the trench contained 0.046 ounce of gold per ton and 0.32 ounce of silver per ton over 25 feet.
Geologic map unit (-147.363748058251, 65.0661779525221)
Mineral deposit model Gold-silver(-arsenic-antimony) vein along shear zone and antimony vein.
Age of mineralization Probably about 90 Ma based on analogy with similar gold deposits nearby.
Alteration of deposit Schist is altered near the veins.

Production and reserves

Workings or exploration The first work on the Ebberts deposit was done by Hugh M. Hinton who hand trenched the prospect (Saunders, 1960). The prospect was inactive until about 1950 when it was dozer trenched by United States Smelting Refining and Mining (USSR&M). In June 1960, Arctic Alaska Fisheries and Enterprises Inc. cut several dozer trenches on the prospect and exposed the Ebberts shear zone which is sometimes referred to as the Jamesonite shear zone (Saunders, 1960). The mine was idle until 1967 when Ed Ebbert reopened the shaft and trenches (Anderson and Johnson, 1970). In 1969, the Ebberts Mine was sampled by International Minerals and Chemicals (IMC) in the vicinity of the main shaft (Pilkington, 1970). IMC also excavated a dozer trench which crossed the Ebberts shear 200 feet east of the Ebberts shaft.
Indication of production Yes; small
Production notes The Ebbert prospect was mined for antimony from a shallow shaft and open cuts from 1961 through 1964 by Ed Ebbert (R. Vetter, oral commun., 1986).

References

MRDS Number A015522

References

Reporters C.J. Freeman, J.R. Guidetti Schaefer (Avalon Development Corporation); D.J. Grybeck (Port Ludlow, WA)
Last report date 6/5/2008