Gites de wollastonite, province tectonique de Grenville, Quebec

CIM Bulletin, Vol. 83, No. 934, 1990

G.J. Simandl, Consultant—Economic Geology and Industrial Minerals, Montréal, G. Valiquette, École Polytechnique de Montréal, Montréal, H.-L. Jacob, Ministere de l'Énergie et des Ressources, Quebec, S. Paradis, Commission Geologique du Canada, Centre Geoscientifique de Québec, Québec

Quebec's portion of the Grenville geological province holds over 100 known wollastonite showings and deposits. Exceptionally favourable sectors for wollastonite exploration are located between the municipality of Grenville and Mont-Tremblant Park (north of St-Jovite). Other promising sectors are located in the Lac-Saint-Jean, Shawinigan and Gatineau areas. Deposits may be classified into nine categories depending on their relationship to intrusive rocks, discordant or concordant contacts with the host rocks, morphology, and major structural controls. Deposits consist mainly of wollastonite, calcite and clinopyroxene. They may contain one or several of the following minerals: feldspar, scapolite, quartz, titanite sulphides, zoisite, clinozoisite, garnet, idocrase andprehnite. Wollastonite content may reach over 70%. Some deposits are associated with graphite veins. Better understanding of the geology, combined with the proposed classification provides new exploration guide for wollastonite. Several deposits have grades of economic interest. Further work is needed to determine if any of these deposits can be exploited for profit.

Mots Clés: Industrial minerals, Wollastonite deposits, Grenville province