Western Mt. Apatite group. - Oxford pegmatite field. (The Dionne extension to the Pulsifer Quarry was excavated during mid-1990s mining.)
http://www.findarticles.com/p/articles/mi_m0GDX/is_1997_Jan/ai_53285854
Mineralogical Record (1977) 8 (2), 72-77;
King, V. T. and Szenics, T., 2008, Pulsifer Quarry, Androscoggin County, Maine, American Mineral Treasures.