Sphalerite, chalcopyrite, covelline, galena and stannite. Rishi, Nigeria
250µm
Sphalerite (light grey, right) is intergrown with chalcopyrite (yellow, centre). Sphalerite contains abundant rounded chalcopyrite inclusions, whereas chalcopyrite has small stannite stars (light brown, centre left). The main sulphides are fractured, and these are infilled by covelline (deep blue, centre) and secondary galena (white, centre right). Quartz is very dark grey (centre left) beneath resin (dark grey) with an air bubble (black); other black areas are polishing pits.
Polished block, plane polarized light, x 80, air