Limonite |
limonite (līm´ənīt) or brown hematite (hĕm´ətīt, hē´–), yellowish to dark brown mineral, a hydrated oxide of iron, FeO(OH)·nH 2 O, occurring commonly in deposits of secondary origin,, those formed by the alteration of minerals containing iron. Both iron rust and bog iron ore are limonite.