(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.
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