A mineral, called by Hauy triphane. It occurs in laminated masses, easily divisible into prisms with rhomboidal bases; the lateral faces smooth, shining and pearly; the cross fracture uneven and splintery. Before the blowpipe it exfoliates into little yellowish or grayish scales; whence its name.

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.