Lost River-Kougarok Sn-W

Region Alaska, Alaska
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Prospective geology, geochemical anomaly, historical production of greisen-related granite Sn deposits, and additional ARDF occurrences.
Identified resources Identified resources of tin and tungsten. Historical production of tin.
Production Lost River mine, 1952-1955.
Status Past mining. Current exploration and re-evaluation of lithium, niobium, and tantalum, fluorspar. Past exploration focused on tin at Lost River mine. 1980s industry drilling at Kougarok for tantalum (current re-evaluation for Sn, Nb, Ta).
Estimated resources Kougarok: 5.7M short tons at 0.39% Sn, with known W; Lost River mine has significant known skarns.
Geologic maps No modern mapping better than 1:250,000 scale.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Evolved felsic intrusions, greisens, carbonate horizons.
Deposits Lost River, Kougarok.
Evidence from mineral occurrences ARDF.
Geochemical evidence Anomalous Sn, W, and other pathfinders in HUC's; granites with appropriate geochemical characteristics of highly evolved compositions.
Geophysical evidence No data.
Evidence from other sources High prospectivity determination based on Karl and others (2016).
Cover thickness and description Unknown.
Authors Douglas C. Kreiner, James V. Jones III, Melanie B. Werdon.
New data needs New mapping, geophysics, and updated geochemical sampling.
Geologic mapping and modeling needs Mapping at 1:100,000 scale or better.
Geophysical survey and modeling needs Aeromagnetics and radiometrics collected at Rank 2.
Digital elevation data needs IfSAR coverage is complete over entire focus area.