Deposits of rare earth elements in Canada

Abstract

Canada has large reserves of rare earth elements (REEs) (estimated to be ∼15.2 Mt of REE oxides). It hosts several advanced exploration projects related either to alkaline (peralkaline) silicate complexes or to carbonatites. Alkaline silicate complexes, which host REE deposits, are composed of rocks ranging from nepheline syenites to peralkaline granites and trachytes and are of Proterozoic age. Advanced projects (Feasibility or Preliminary economic assessment stage) include Nechalacho (Northwest Territories), Strange Lake, Crater Lake, Kipawa (all in Quebec), and Foxtrot (Labrador). The alkaline silicate mineralization type is one of the most important sources of heavy REEs including Y. Mineralized carbonatites are the main source of light REE. Advanced projects include Ashram/Eldor in Quebec and Wicheeda in British Columbia. The main REE minerals in both types of these deposits are fluorocarbonates (bastnaesite), phosphates (monazite, apatite) and in silicate rocks also silicates (eudialyte). These deposits may contain significant concentrations of Zr (zircon), Nb (columbite, fergusonite, pyrochlore), and Th–U (monazite, uraninite, thorite). In addition, there are several other less advanced projects (with resource estimate only). They include carbonatite of Montviel and Saint-Honoré in Quebec, Prairie Lake, and Clay-Howells in Ontario as well as alkaline silicate project at Red Wine Mountains in Labrador. It is anticipated that Canada would be a global leader in the production of REEs.