Chromite, chalcopyrite and rutile. Bushveld, Republic of South Africa
Euhedral, fractured cubic crystals of chromite (medium grey) are intergrown with silicate (dark grey). A single lath of rutile (light grey, centre) is partially enclosed in chromite and partly in silicate. Minor amounts of interstitial chalcopyrite (yellow, left centre) are present. Black areas are polishing pits.
Polished block, plane polarized light, x 40, air