Primary pyrochlore occurs as rounded anhedra as large as an inch across in the wall-zone rock of pegmatites in the Calvin Township of the Nipissing district, several miles S. of Eau Claire. The scarcity of Fe (or Fe + Mn) and the concentration of Ca in the wall-zones allowed the pyrochlore rather than the more usual columbite to form. Eulysite outcrops in concession V, Calvin Township, W. of Amable du Fond River and SW. of Smith Lake. The rock contains euhedral porphyroblasts of labradorite up to 1.3 X 3.8 cm in section, hedenbergite (some as vermicular intergrowths in garnet), fayalite, magnetite, apatite, and hornblende with minor amounts of biotite and olivine.

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