Nepheline syenite. The Princess Sodalite quarry has a century long history and is still being worked at present. The quarry itself is currently closed to the public due to safety concerns.
References:
Sabina, A.P. (1982): Some rare minerals of the Bancroft area. Mineralogical Record 13 (4), 226-228
Sabina (1986) Rocks and Minerals for the Collector. Bancroft-Parry Sound Area and Southern Ontario, Geol. Survey of Canada, Misc. Report 39, 11-14.
Steacy, H.R., Rose, E. R., Moyd, L. & Hogarth, D.D. (1982): Some classic Mineral Localities of Southeastern Ontario. Mineralogical Record 13: 197-203
Mineral List:23 entries listed. 17 valid minerals.
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