Pentlandite, pyrrhotite, pyrite and chalcopyrite. Bushveld, Republic of South Africa
Pentlandite (brown, top centre) with (111) cleavage is intergrown with pyrrhotite (pink-brown, top right). Chalcopyrite (yellow, centre right) and pyrite (pale yellow-white, centre) form rims around pentlandite. Black areas are polishing pits, the dark grey area is the mounting resin with small round gas bubbles (black, bottom left).
Polished block, plane polarized light, x 40, air