ilmenite

ilmenite , black mineral, iron titanium oxide, FeTiO ₃ , crystallizing in the hexagonal system. It is sometimes found as tabular hexagonal crystals but occurs more commonly as small grains in igneous and metamorphic rocks and in sands derived from them. Ilmenite has been noted as an important constituent of lunar rocks. It is the commonest titanium mineral and is the most important source of this element and its compounds. Over 3 million tons of ilmenite are mined annually; important producers are the United States, Canada, Australia, and Norway.

ilmenite Mineral, FeTiO₃; sp. gr. 4.5–5.0; hardness 5–6; trigonal; black; black to brownish-red streak; sub-metallic lustre; crystals normally thick and tabular, but often massive and compact; no cleavage; magnetic; occurs as an accessory mineral in igneous rocks, e.g. gabbro and diorite, in quartz veins and pegmatites, in gneisses, in association with hematite and chalcopyrite, and because it is resistant to weathering it occurs extensively in alluvial deposits with magnetite, monazite, and rutile. It is used as a source of iron and titanium. The name is derived from that of the Ilmen Mountains, Russia.