Granite pegmatite. Feldspar quarry first opened in 1916. Later, Kenneth K. Landes, then a Harvard University student, based his research both on this quarry and the Noyes Mountain (Harvard) Quarry in Greenwood and his dissertation revolutionized ideas about how pegmatites crystallize. Landes' paper was "Paragenesis of the Granitic Pegmatites of Central Maine", (American Mineralogist, 1925, v. 10, p. 355-411). Oxford pegmatite field.
Refs.:
King, V. and Foord, E, 1994, Mineralogy of Maine, v. 1.
King, V. and Foord, E., 2000, Mineralogy of Maine, v. 2.
Landes, K., American Mineralogist (1925): 10: 355-411.
Rocks & Minerals: 14: 273.
Rocks & Minerals: 62: 396.
Mineralogical Record: 25(3): 175-184.
Perham Stevens, J. (1972), Gems & Minerals of Oxford County.
http://www.coromotominerals.com/index.html [mine owner]
73 entries listed. 55 valid minerals. 3 erroneous literature entries.