Hematite is an iron oxide. This mineral is 70% iron and 30% oxygen by weight. It goes through the process of igneous, sedimentary, and metamorphic stages. Hematite is crystallized when there is differentiation between the magma and hyperthermal fluids passing through rock are precipitated. It is also formed when magma interacts with adjacent rocks. Hematite is one of the most abundant minerals on Mars according to NASA. It can come in the colors can be from reddish-brown to a black mineral. Hematite can also be magnetic.
Hematite being made of iron is ruled by Mars.