Sphalerite, native gold, pyrrhotite and chalcopyrite. Pamour Mine, Ontario, Canada
Sphalerite (grey-brown, left) encloses a small crystal of pyrrhotite (light brown, centre), chalcopyrite (yellow, centre left) and native gold (yellow, centre bottom). It is very difficult to distinguish the chalcopyrite and gold at this magnification, but to the eye the gold grain has a stronger surface colour. Coarse-grained native gold (yellow, high reflectance, bottom right) is scratched and grows around the sphalerite or infills fractures in the silicates (dark grey).
Polished block, plane polarized light, x 160, air