Cubanite, chalcopyrite, pyrrhotite, magnetite and pyrite. Bushveld, Republic of South Africa
125µm
Chalcopyrite (yellow, centre left) is intergrown with cubanite (light brown, centre) which forms broad and very fine lamellae within chalcopyrite as an exsolution texture. Pyrrhotite (brown, left centre) occurs on the margin of chalcopyrite, has a deeper surface colour than cubanite and shows reflection pleochroism. Magnetite (grey, left centre) shows cleavage. Minor amounts of pyrite (white, right centre) associated with magnetite lie within the chalcopyrite-cubanite intergrowth. Silicates are black. Cubanite and chalcopyrite can be difficult to distinguish from each other in plane polarized light.
Polished block, plane polarized light, x 160, oil