Also found in: Dictionary, Thesaurus, Wikipedia.
alabaster,fine-grained, massive, translucent variety of gypsumgypsum
, mineral composed of calcium sulfate (calcium, sulfur, and oxygen) with two molecules of water, CaSO4·2H2O. It is the most common sulfate mineral, occurring in many places in a variety of forms. A transparent crystalline variety is selenite.
..... Click the link for more information. , 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 marblemarble,
metamorphic rock composed wholly or in large part of calcite or dolomite crystals, the crystalline texture being the result of metamorphism of limestone by heat and pressure.
..... Click the link for more information. , 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.
A fine-grained, translucent variety of very pure gypsum, white or delicately shaded, and used for ornamental work.See also: Stone
CaSO4·2H2O A fine-grained, colorless gypsum.
Fine-grained, translucent variety of very pure gypsum, generally white or delicately shaded.
1. a fine-grained usually white, opaque, or translucent variety of gypsum used for statues, vases, etc.
2. a variety of hard semitranslucent calcite, often banded like marble