Bornite, covelline and sulphosalt. Levant Mine, Cornwall, Britain
Bornite (brown, bottom right) is intergrown with covelline (blues) which shows good cleavage, bireflectance and reflection pleochroism. Trace amounts of an uncharacterized sulphosalt (cream-white, bottom right) are intergrown with bornite. Black areas are polishing pits.
Polished block, plane polarized light, x 80, air