Prospect, Probably inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale CR
Quadrangle map, 1:63,360-scale B-3
Latitude 55.34978
Longitude -132.80162
Nearby scientific data Find additional scientific data near this location
Location and accuracy The location of this old prospect, which is described only by Chapin (1916), is not known precisely. It probably is about midway between the heads of Trocadero Bay and Twelvemile Arm, within a mile of the center of the SE1/4 section 21, T. 75 S., R. 83 E.

Geologic setting

Geologic description

The Nancy prospect is in greenstone interbedded with argillite and conglomerate (Chapin, 1916). The rocks are part of the Descon Formation of Silurian and Ordovician age (Eberlein and others, 1983; Brew, 1996). The deposit consists of a shear zone 25 feet wide that contains silicified greenstone with pyrite and chalcopyrite. Some quartz stringers also contain pyrite and chalcopyrite. A quartz vein 6 feet thick strikes N70E and dips 45NW. The only workings are shallow trenches.
Geologic map unit (-132.803264655817, 55.3494277149386)
Mineral deposit model Shear zone with chalcopyrite and pyrite.
Age of mineralization Unknown, other than that the deposit is in Silurian and Ordovician rocks.
Alteration of deposit Greenstone in a mineralized shear zone is silicified.

Production and reserves

Workings or exploration Only surface trenching.
Indication of production None