siderite
Sid"er*ite, n. Etym: [L. sideritis loadstone, Gr. 1. (Min.) (a) Carbonate of iron, an important ore of iron occuring generally in cleavable masses, but also in rhombohedral crystals. It is of a light yellowish brown color. Called also sparry iron, spathic iron. (b) A meteorite consisting solely of metallic iron. (c) An indigo-blue variety of quartz. (d) Formerly, magnetic iron ore, or loadstone. 2. (Bot.) Defn: Any plant of the genus Sideritis; ironwort.