Bravoite, nickeliferous pyrite, pyrite, chalcopyrite and covelline. Oxclose Mine, South Pennines, Britain
Subhedral bravoite (pink-brown, left) is enclosed within nickeliferous pyrite (light brown-white, top centre). Coarse grained, faintly zoned, euhedral nickeliferous pyrite (centre right) has a partial pyrite rim (slightly higher reflectance, centre), but this is difficult to see. Chalcopyrite (yellow, centre) is partially altered to covelline (blue).
Grain mount, plane polarized light, x 160, oil