Basis for focus area |
Clark Ledge pegmatite (western of 2 polygons) and Long Hill pegmatite (eastern of 2 polygons) (Bradley and others, 2016). Rocky Hill (eastern) also noted by Billings and Wolfe (1944). |
Identified resources |
Historical production of lithium (spodumene). |
Production |
Spodumene production (to 50 feet depth) at Long Hill estimated to be 10,000 to 20,000 tons; average spodumene contained 10.4% Li (Billings and Wolfe, 1944). |
Status |
Past mining. |
Estimated resources |
Unknown. |
Geologic maps |
Peper and Wilson (1978), scale 1:24,000; Hatch and Warren (1982), scale 1:24,000; Holmes (1968), scale 1:24,000; Hepburn (2016), scale 1:24,000. |
Geophysical data |
Inadequate Rank 3 to 4 aeromagnetic coverage and Rank 4 aeroradiometric coverage. |
Favorable rocks and structures |
Pegmatite associated with granite in graphitic schist. |
Deposits |
Clark Ledge lithia mine (MRDS dep_id: 10067347), Long Hill, Taylor Ledge lithia mine (MRDS dep_id: 10067345). |
Evidence from mineral occurrences |
MRDS; Bradley and others (2016). |
Geochemical evidence |
Spodumene occurs in exceptional abundance; spodumene pegmatites also contain minor amounts of green to blue tourmaline, as well as amblygonite, pollucite, and purpurite (Billings and Wolfe, 1944). |
Geophysical evidence |
Unknown. |
Evidence from other sources |
Unknown. |
Comments |
Two polygons are included for the two areas of pegmatite. See Pearre (1956), Billings (1941; 1944) and Billings and Wolfe (1944) and Bradley and others (2016). Bradley and others (2016) locate Clark Ledge at (42.4199, -72.8719) and Long Hill at (42.5064, -71.7822) (datum not given in publication). |
Cover thickness and description |
Exposed at the surface. |
Authors |
Gregory J. Walsh, Nora K. Foley, Stephen B. Mabee. |
New data needs |
Detailed geologic mapping >1:24,000; geophysics. |
Geologic mapping and modeling needs |
Existing 1:24,000 scale mapping may be adequate. |
Geophysical survey and modeling needs |
High resolution aeromagnetic and aeroradiometric data can assist with framework geology such as structural features and contacts. |
Digital elevation data needs |
Liar complete or planned/funded. |