Ilmenite

Ilmenite is the most important ore of titanium. It is similar in appearance to magnetite, but has a different crystal form and if it is magnetic then it's not as strongly so as magnetite. It will become magnetic when heated.

Ilmenite is a common accessory mineral in many igneous rocks and also found as a detrital mineral (in sands).

Chemical composition - FeTiO ₃
Hardness - 5-6
Specific gravity - 4.5-5
Transparency - Opaque
Colour - Black
Streak - Black
Lustre - Metallic
Cleavage/fracture - Non-existent / conchoidal
Crystal habit/mode of occurrence - Tabular (thin and thick tabular crystals with rhombohedral truncations, sometimes formed into rosettes) / massive and granular, as grains in some sands