A mineral form of iron (III) oxide,
It is the most important ore of iron and usually occurs
in two main forms as a massive red kidney-shaped ore
(kidney ore) and as grey to black metallic crystals
known as specular iron ore.
Haematite is the major
red coloring agent in rocks; the largest deposits
are of sedimentary origin.
In industry haematite
is used as a polishing agent (jeweler’s rouge)
and in paints.