| Basis for focus area |
MRDS occurrences. |
| Identified resources |
Historical production of beryllium (beryl). |
| Production |
Cannon mine: 6 tons of ore mined and stockpiled; average grade 4.2-6.21% BeO. |
| Status |
Past mining for beryllium (beryl). |
| Estimated resources |
Unknown. |
| Geologic maps |
Miller (1974), scale 1:62,000; Miller and others (1975), scale 1:62,000; Park and Cannon (1943), scale 1:96,000; Miller (2000), scale 1:100,000. |
| Geophysical data |
Inadequate aeromagnetic coverage and some adequate aeroradiometric coverage. |
| Favorable rocks and structures |
Pegmatite dike swarms related to the emplacement of two-mica granites of the Cretaceous Phillips Lake granodiorite. |
| Deposits |
Cannon mine (MRDS dep_id: 10042366), Railway Dike mine (MRDS dep_id: 10254032). |
| Evidence from mineral occurrences |
MRDS. |
| Geochemical evidence |
Cassiterite is the only Sn mineral and is disseminated in both types of pegmatite. Wolframite and scheelite (the most abundant W mineral) are found in quartz pegmatites and veins. An ore shoot ~100 ft by 20 ft, and 2-3 ft thick is estimated to contain approximately 3% metallic Sn (Page, 1942). |
| Geophysical evidence |
None. |
| Evidence from other sources |
None. |
| Comments |
Mostly national forest and state owned land (mineral leases). Some national wildlife refuge in west central portion in the study area and private ownership scattered throughout. |
| Cover thickness and description |
Exposed at the surface. |
| Authors |
Daniel W. Eungard. |
| New data needs |
High resolution geophysics and mapping, geochemistry, and lidar. |
| Geologic mapping and modeling needs |
Seven 1:24,000 scale quadrangles worth of area covered by focus area. Reconnaissance mapping to find dike swarms. Geochemistry to verify element enrichments in dikes. |
| Geophysical survey and modeling needs |
High-resolution, Rank 1 aeromagnetic and aeroradiometric surveys. |
| Digital elevation data needs |
Lidar complete over small portion of focus area. |
