Sphalerite, galena, haematite and magnetite. Jersey, Channel Islands, Britain
250µm
Final polishing with ¼ µm diamond paste. Despite a wide variation in hardness between the phases, there is little relief. Sphalerite (light grey, left) is intergrown with galena (White, centre) and euhedral magnetite (brown, bottom centre). Haematite (pale blue, bottom centre) laths are being replaced by galena (centre). The gangue is quartz (dark grey, bottom centre) and abundant coarse-grained carbonate with a slightly higher reflectance than quartz.
Polished block, plane polarized light, x 80, air