Unnamed (north of hill 2170)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Hg
Other commodities As
Ore minerals pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale ID
Quadrangle map, 1:63,360-scale C-1
Latitude 62.74318
Longitude -156.23425
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 1,600 feet about 1.0 mile north of hill 2170. It is about 0.3 mile northeast of the southwest corner of section 28, T. 31 N. R. 37 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description

This occurrence is a pyrite-quartz-bearing shear zone about 65 feet thick that occurs at the contact of a small granite porphyry intrusion with biotite hornfels (Miller and Bundtzen, 1994; Miller, Bundtzen, and Gray, 2005). The rocks in the vicinity are mainly fine grained intrusive rocks and a large hornfels aureole; this suggests a large underlying intrusive body (Miller and Bundtzen, 1994). The mineralized shear zone can be traced for about a mile to the northeast. Grab samples collected along the zone contain 1,000 parts per million (ppm) mercury (D. Obolewicz, written communication, 1981). Other samples contain up to 500 parts ppm arsenic but no gold (McGimsey and others, 1988).
Geologic map unit (-156.236614996235, 62.7425419551258)
Mineral deposit model Polymetallic vein? (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c?
Age of mineralization Unknown; the nearby intrusion is undated (Miller and Bundtzen, 1994).
Alteration of deposit Sericite.

Production and reserves

Workings or exploration The mineralized shear zone was sampled by Anaconda Minerals in 1981 (D. Obolewicz, written communication, 1981 and the U.S. Geological Survey in 1986 (McGimsey and others, 1988).
Indication of production None

References