Unnamed (south of Nun Mt.)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; pyrite
Gangue minerals epidote; garnet; quartz

Geographic location

Quadrangle map, 1:250,000-scale JU
Quadrangle map, 1:63,360-scale B-4
Latitude 58.4954
Longitude -135.2535
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is 1/2 mile south of Nun Mountain and 4 miles northwest of Mount Golub at an elevation of approximately 2,000 feet. It is near the northeast corner of section 13, T. 39 S., R. 61 E. of the Copper River Meridian. The location shown is accurate within 1/2 mile.

Geologic setting

Geologic description

The general area is underlain by deformed and metamorphosed Silurian or Devonian carbonate, clastic and volcanic clastic rocks that have been intruded by Upper Jurassic and Lower Cretaceous granitic and dioritic rocks (Brew and others, 1992). This occurrence is one of several widely scattered skarn deposits in the area between Nun Mountain and just south of Mount Golub, where a Cretaceous granodiorite pluton intrudes a thick limestone unit (Clough and Redman, 1989). Numerous small garnet-epidote skarns occur along the contact between the granodiorite and the limestone. Wells and others (1986) describe pyrite veinlets in limestone and silicified argillite near a granodiorite contact at this locality. The U.S. Bureau of Mines noted several small, discontinuous garnet-epidote skarns up to a foot thick and several feet long, that contain sparse chalcopyrite and pyrite (Clough and Redman, 1989).
Geologic map unit (-135.255307318642, 58.4950679179711)
Mineral deposit model Cu skarn deposit (Cox and Singer, 1986; model 18b)
Mineral deposit model number 18b

Production and reserves

Workings or exploration Surface samples only.
Indication of production None

References