Prospect, Inactive

Alternative names

Forlorn Hills

Commodities and mineralogy

Main commodities Sn
Ore minerals cassiterite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale TA
Quadrangle map, 1:63,360-scale B-5
Latitude 60.2695
Longitude -157.7671
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is on an isolated upland south of the middle section of the Salmon River. It is near elevation 2280, about 0.4 mile north of the center of section 15, T. 2 N., R. 49 W.

Geologic setting

Geologic description

A zone of surface rubble about 50 feet long and 10 to 15 feet wide is marked by pieces of quartz-veined stockworks and breccia (Travis Hudson, unpublished field data, 2005). The upland in the area consists of hornfels developed in clastic sedimentary rocks of the Cretaceous Kuskokwim Group; porphyroblastic hornfels with cordierite and/or andalusite porphyroblasts is common. Sparse quartz and quartz-tourmaline veining is locally developed. Intrusive rocks are not exposed on hills 2280, 1866, and 1610. Float from a few-centimeter-thick felsic dike was found at an elevation of about 500 feet on the southwest flank of hill 1750. Cominco Exploration identified cassiterite and high-grade tin values in the quartz breccia.
Geologic map unit (-157.769338830833, 60.2687886142324)
Mineral deposit model Quartz vein breccia in hornfels.
Age of mineralization Probably Early Tertiary, the age of the tin mineralization at the nearby Sleitat Mountain prospect (TA010).
Alteration of deposit Silicification of hornfels.

Production and reserves

Workings or exploration Surface examination and rock sampling. This prospect was originally discovered by and staked during a reconnaissance exploration program by Cominco Exploration in the early 1980s.
Indication of production None


Reporters Travis L. Hudson (Applied Geology, Inc.)
Last report date 10/10/2005