Magnetite, iron, haematite and limonite. Scotland
250µm
A magnetic separate in which angular magnetite (brown grey), a coarse-grained crystal of haematite (blue-grey, centre top left) and limonite (blue-grey, low reflectance, centre bottom left) are natural phases. Tramp iron (white, high reflectance) occurs as long splinters or curved flakes (right centre). The grey matrix is resin.
Grain mount, plane polarized light, x 80, air