Chalcopyrite, pyrite, chrome-rich spinel, magnetite, altered pentlandite and violarite. Kambalda, Western Australia
250µm
The central spinel phase is zoned with a lower reflectance core (light grey, centre) of chrome-rich spinel (ferrochromite) and a higher reflectance iron-rich rim (magnetite) (bottom centre). It is extensively shattered and the fractures are infilled with chalcopyrite. Chalcopyrite (yellow, left) is intergrown with pyrite (pale yellow-white, higher reflectance, right) and euhedral to subhedral highly altered pentlandite (light yellow brown, many polishing pits, top centre). Violarite (brown, top right) is the main alteration product of pentlandite. Dark grey areas are silicates.
Polished block, plane polarized light, x 80, air
