Cryolite

n. [Fr. cryolithe, from Gr. κρύος, icy cold, frost, and λίθος, stone.] (Min.) A fluoride of sodium and aluminum, found in Greenland, of a pale, grayish-white, snow-white, or yellowish-brown color. It occurs in cleavable masses, and has a glistening, vitreous luster. Dana.