hematite

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hematite (haematite, iron glance, kidney ore, red iron ore, specularite) Iron mineral, Fe2O3; one of the main ores for iron; sp. gr. 4.9–5.3; hardness 5–6; trigonal; steel-grey to black, often iridescent, compact varieties dull to bright red; red to reddish-brown streak; metallic lustre; crystals tabular or rhombohedral with curved, striated faces, also occurs as columnar, mammillated, and botryoidal masses; no cleavage; widely distributed as an accessory mineral in igneous rocks, hydrothermal veins, as a rock-forming mineral in sedimentary rocks, as a primary mineral, as concretions or a cementing agent, and as a replacement for other minerals. Bedded ores of hematite form huge deposits in the Precambrian of N.America and elsewhere. See BANDED IRON FORMATION (BIF).

hematite

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he·ma·tite / ˈhēməˌtīt/ (Brit. hae·ma·tite) • n. a reddish-black mineral consisting of ferric oxide. It is an important ore of iron.

hematite

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hematite One of the most important iron ores, containing mainly ferric oxide, Fe2O3. Containing 70% iron by weight, it occurs in several forms and from steel-grey to black in colour.