Haematite, chalcopyrite, pyrite and rutile. Los Bronces Mine. Chile
250µm
Coarse-grained haematite (light grey-blue, left), chalcopyrite (yellow, centre left) and pyrite (light yellow-white, high reflectance, centre left) are intergrown with radiating laths of tourmaline (light grey, left). An aggregate of rutile crystals (grey-white, centre right) is enclosed within a mosaic of coarse-grained quartz crystals (dark grey with faint internal reflections, right). Black areas are polishing pits.
Polished block, plane polarized light, x 80, air
