Crystal

(kris'tal.) [Gr. krystal los, congealed.] (Chem. and Min.) An inorganic body, which has a umed the form of a regular solid, terminated by a certain number of plane and smooth surfaces. C. maybe formed in various ways. Some are formed by the evaporation of afluid holding crystalline substances in solution; or by the pa age of a body from the fluid to the solid state, as in the case of most metals; or they maybe deposited by the vapor of a volatilized body.-C. gla . (Manuf.) A substance more perfect in its composition than common gla . It is frequently cut; and vases, lustres, and other ornaments are made of it.- Iceland C. (Min.) A var. of calcareous spar, or crystallized carbonate of lime, remarkable for its double refraction; -it is brought from Iceland, whence the name. [s. 249]