What is a mineral of a white to yellowish, purplish, or emerald-green color, occuring in prismatic crystals, often of great size. It is a silicate of aluminia and lithia. See Hiddenite called?

spodumene — A mineral of a white to yellowish, purplish, or emerald-green color, occuring in prismatic crystals, often of great size. It is a silicate of aluminia and lithia. See Hiddenite. (Webster's 1913.)

Sources