Pyrrhotite, pentlandite, pyrite and chalcopyrite. Kambalda, Western Australia
200µm
Coarse-grained pentlandite (yellow-brown, centre and right) shows characteristic cleavage along (111) and is intergrown with pyrrhotite (pink-brown, lower reflectance than pentlandite, left and bottom right). Pyrrhotite has rims of pyrite (white, centre bottom) and chalcopyrite (centre) which has tarnished to a dull yellow. Minor amounts of pyrite form areas within pyrrhotite along crystal boundaries (top left). Dark grey areas are silicates and black areas are polishing pits.
Polished block, plane polarized light, x 100, air
