alabaster

alabaster fine-grained, massive, translucent variety of gypsum , a hydrous calcium sulfate. It is pure white or streaked with reddish brown. Alabaster, like all other forms of gypsum, forms by the evaporation of bedded deposits that are precipitated mainly from evaporating seawater. It is soft enough to be scratched with a fingernail and hence it is easily broken, soiled, and weathered. Because of its softness, alabaster is often carved for statuary and other decorative purposes. It is quarried in England and also in Italy. Vases and statuettes of Italian alabaster are sold as "Florentine marbles." The term "Oriental alabaster" is a misnomer and actually refers to marble , a calcium carbonate; whereas gypsum is a calcium sulfate. Important sources of alabaster are Algeria, Egypt, Iran, and Mexico (from which it is exported under the name Mexican onyx); in the United States there are important sources in Utah and Arizona. Oriental alabaster (marble) was extensively used by the Egyptians in sarcophagi, in the linings of tombs, in the walls and ceilings of temples, and in vases and sacrificial vessels. The Romans worked the Algerian and Egyptian quarries and used the stone for similar purposes. In modern times it was used by Muhammad Ali for his mosque in Cairo. The French make extensive use of alabaster in interior decoration.