Knox Mountain pluton

Region East, Northeast
Mineral systems
Deposit types
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Skarn in impure marbles of the Waits River and Gile Mountain Formations around the Devonian New Hampshire Plutonic Suite, especially the Knox Mountain and Averill plutons.
Identified resources Unknown.
Production Unknown.
Status Unknown.
Estimated resources Unknown.
Geologic maps Konig (1961), scale 1:62,500; Murthy (1957), scale 1:62,500; Ratcliffe and others (2011), scale 1:100,000.
Geophysical data Partly (~50%) adequate aeromagnetic data, inadequate aeroradiometric data.
Favorable rocks and structures Skarn around Devonian plutons or granite-related hydrothermal mineral deposits. Primarily the Knox Mountain pluton, but may include the Averill pluton and other Devonian plutons. Source of scheelite found in pan-concentrates is not confirmed.
Deposits None.
Evidence from mineral occurrences Scheelite in pan concentrates.
Geochemical evidence Geochemical data in Slack (1990) and Watts (1990).
Geophysical evidence Unknown.
Evidence from other sources Lac Lyster in Quebec (Gauthier and others, 1994).
Comments Potential resource but source of scheelite is not known in Vermont. Evidence comes from deposits at Lac Lyster in southern Quebec on the north side of the Averill pluton where "skarn-hosted scheelite mineralization occurs within 400 m of the intrusive contact with grades of 3% WO3 but most mineralization ranges from 0.1 to 0.4% WO3" (Gauthier and others, 1994, p. 1342).
Cover thickness and description Exposed bedrock or glacial till and lacustrine deposits generally less than 10-50 m.
Authors Gregory J. Walsh, John F. Slack.
New data needs Geochemistry, geophysical surveys, geological mapping.
Geologic mapping and modeling needs 1:24,000 scale mapping is needed.
Geophysical survey and modeling needs Complete high resolution aeromagnetic and aeroradiometric coverage.
Digital elevation data needs Lidar adequate.