Sphalerite, galena and chalcopyrite. Unknown Provenance
Sphalerite (light grey), galena (white, top left) and chalcopyrite (yellow, centre top) are complexly intergrown. Galena has penetrated along cleavages in the silicates (centre, right centre). Dark grey areas are amphibole (top right), quartz and other silicates.
Polished block, plane polarized light, x 80, air