Monoclinic pyrrhotite, hexagonal pyrrhotite, magnetite, chalcopyrite and pentlandite. Strathcona Mine, Sudbury, Ontario, Canada
Rhomb-shaped areas of deeply etched hexagonal pyrrhotite (lower 'reflectance, mottled brown-grey, centre and top right) are surrounded by more lightly etched monoclinic pyrrhotite, which is the main phase. Very lightly etched monoclinic pyrrhotite (pale brown, bottom right) has a rim of granular pentlandite (light brown, higher reflectance, bottom right). Pyrrhotite is intergrown with chalcopyrite (yellow, centre) and encloses subhedral magnetite (grey, top left), some of which is lightly etched (left bottom).
Polished block (etched with HI), plane polarized light, x 80, air