Pyrrhotite, sphalerite, chalcopyrite and graphite. Great Gossan Lead, Virgi

Click here


Pyrrhotite (brown) shows deformation twin lamellae (higher reflectance, centre top) and plucking along its (0001) cleavage (black pits, centre top). Both inclusion-free sphalerite (light grey, centre bottom) and sphalerite with abundant chalcopyrite (yellow) inclusions along crystallographic directions (top right) are present. A curved flake of graphite (brown, low reflectance, centre) lies across a pyrrhotite-sphalerite junction close to a silicate grain. Black areas are polishing pits.

Polished block, plane polarized light, x 80, air

Click here for Associations Click here for Mineralogy Click here for high-res image (~300K)