Alabaster, a variety of Gypsum (q.v.) or Selenite (q.v.). Chemically, these are all forms of the hydrated sulphate of calcium (hydrated sulphate of lime). Anhydrite (q.v.) is anhydrous sulphate of calcium. Both alabaster and anhydrite are used as ornamental stones. Alabaster, though softer, resembles marble in general appearance. When free from foreign substances, it assumes a finely grained structure, is of a pure white or delicately tinted colour, and is beautifully translucent. Of this class is the celebrated alabaster of Volterra in Tuscany. But it is often elegantly veined, striped, or spotted. Great numbers of beautiful statuettes, and ornaments of different kinds, are made of this material in Italy. It is found of good quality in Derbyshire, where it is also worked up into ornaments. Alabaster is slightly soluble in water, so that it is unsuitable for external work; but it does well for internal panelling or other decoration, the only drawback being the difficulty of finding it in large pieces.
Oriental Alabaster is a stalactitic carbonate of calcium (carbonate of lime), a mineral substance different from and harder than ordinary alabaster. It is really a variety of marble, and is found in Egypt, where it was worked in ancient times for urns, jars, and the like. The same kind of rock, which is sometimes extremely beautiful, is found in other parts of the world.
The name alabaster is said to be derived from the name of a town in Egypt where this kind of stone was abundant, and was manufactured into pots for perfumes. Such pots were called alabastra, even when made of other materials.