1540s, haematites, from Middle French hematite (16c.), from Latin haematites, from Greek haimatites lithos "bloodlike stone," from haima (genitive haimatos) "blood" (see -emia). Earlier as emachite (late 14c.).
A reddish-brown to silver-gray metallic mineral. Hematite occurs as rhombohedral crystals, as reniform (kidney-shaped) crystals, or as fibrous aggregates in igneous, metamorphic, and sedimentary rocks. It is the most abundant ore of iron, and it is usually slightly magnetic. Chemical formula: Fe2O3.