(1):
(n.) 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.
(2):
(n.) A meteorite consisting solely of metallic iron.
(3):
(n.) An indigo-blue variety of quartz.
(4):
(n.) Formerly, magnetic iron ore, or loadstone.
(5):
(n.) Any plant of the genus Sideritis; ironwort.