| Basis for focus area |
Outline of pegmatite mines and occurrences included in the Crystal Mountain mining district, which encompasses a few dozen historically productive beryl mines. Proterozoic-age pegmatites may not associated with Climax-type deposits. |
| Identified resources |
Identified resources of beryllium (beryl). Historical production of beryllium (beryl), mica, and uranium. |
| Production |
The Hyatt mine produced 34 tons of beryl, The Wisdom Ranch mine produced ~ 15 t of beryl, and the Buckhorn Mica mine produced about ~2 t beryl and 180 tons of ground mica (Hanley and others, 1950). Byproduct U production at Hide Above lode (~ 0.045 equivalent U3O8) and various others. |
| Status |
Past mining. |
| Estimated resources |
Estimated resource of 1,100 to 2,100 t beryl (0.02 to 0.08 wt.% BeO) at Hyatt Ranch mine. Buckhorn Mica mine contains 250 to 500 t beryl (Hanley and others, 1950). The authors note potential for larger resources due to abundance of finer grained beryl. |
| Geologic maps |
Thurston (1955), scale 1:6,000; Braddock and LaFountain (1988), scale 1:24,000; Braddock and others (1989), scale 1:24,000; Braddock and others (1970), scale 1:24,000; Bucknam and Braddock (1989), scale 1:24,000; Braddock (1988), scale 1:24,000. |
| Geophysical data |
Inadequate aeromagnetic and aeroradiometric coverage. |
| Favorable rocks and structures |
Pegmatites intruding quartz-mica schists of the Idaho Springs Formation, Longs Peak batholith. |
| Deposits |
Hyatt Ranch mine (MRDS dep_id: 10013857), Double Opening mine, Buckhorn Mica mine, Wisdom Ranch prospect, Silica Beryl mine, Hide Above lode, Glen O. Barrett, Primrose Beryl lode. |
| Evidence from mineral occurrences |
MRDS; Hanley and others (1950). |
| Geochemical evidence |
Available sample data are sparse: indicate historical ore grade from 0.02 to 0.07 wt.% BeO. Modal beryl potentially as high as 10% from Wisdom Ranch prospect. |
| Geophysical evidence |
Unknown. |
| Evidence from other sources |
Unknown. |
| Comments |
Proterozoic-age pegmatites. Some critical commodities are inferred from mineral system/deposit type table (Hofstra and Kreiner, 2020). |
| Cover thickness and description |
Pegmatite exposed at the surface. |
| Authors |
Ryan D. Taylor, Jane M. Hammarstrom, Joshua M. Rosera, V.J.S. (Tien) Grauch. |
| New data needs |
Geochemical sampling. |
| Geologic mapping and modeling needs |
Unnecessary as entire district covered by 1:24,000 scale geologic maps of Braddock and others (1970; 1989). |
| Geophysical survey and modeling needs |
High resolution Rank 1 aeromagnetic and aeroradiometric survey may not work well with this deposit type, except if help is needed in geologic mapping of different petrologic characteristics. |
| Digital elevation data needs |
Needs lidar coverage. |
