Grafton Pegmatite District

Region East, Northeast
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Grafton pegmatite district (Palermo mine). See Cameron and others (1954) Bradley, McCauley and Stillings (2017), Meyers and Stewart (1956), and Gazdik and others (1988).
Identified resources Historical production of beryllium (beryl), feldspar, and mica.
Production Unknown.
Status Past mining.
Estimated resources Unknown.
Geologic maps Englund (1976), scale 1:62,500; Moke (1946), scale 1:62:500; Smith and others (1939), scale 1:62,500; Quinn (1941), scale 1:62,500; Lyons and others (1997), scale 1:250,000; Thompson (2008b), scale 1:24,000.
Geophysical data Inadequate Rank 4 aeromagnetic coverage and Rank 5 aeroradiometric coverage.
Favorable rocks and structures Pegmatites are near the contact between biotite gneiss and sillimanite-mica schist, principally in the schist (Olson, 1942).
Deposits Palermo 1 mine (MRDS dep_id: 10084534), Ruggles feldspar-mica mine (MRDS dep_id: 10223088).
Evidence from mineral occurrences MRDS.
Geochemical evidence Favorable mineralogy and rock type.
Geophysical evidence Unknown.
Evidence from other sources Unknown.
Cover thickness and description Exposed at the surface.
Authors Nora K. Foley, Dwight C. Bradley, Anjana K. Shah, Gregory J. Walsh, Bernard E. Hubbard.
New data needs Detailed geologic mapping.
Geologic mapping and modeling needs Detailed mapping of pegmatite bodies, geophysics may not be useful for pegmatites.
Geophysical survey and modeling needs High resolution aeromagnetic and aeroradiometric data to assist with framework geology such as structural features and contacts.
Digital elevation data needs Lidar complete.