Alabaster is the name given to the source location Alabaston in Egypt. Alabaster chemical formula is CaSO4.2H2O and it is variety of gypsum. Alabaster, a beautiful, translucent, fine-grained stone, has been prized for thousands of years. It is similar to marble, and the two stones are often confused. Alabaster has been quarried for centuries in Italy and Egypt, although most so called alabaster artifacts from ancient Egypt and Rome are actually marble. Adding to the confusion, the term “onyx” has been applied variously to marble, alabaster, and true onyx, which is a form of quartz. The smooth, translucent appearance of alabaster resembles highly polished marble or onyx. The variety of colour and veining seen in various types of alabaster is also reminiscent of coloured or white marble. Alabaster is the fine grained form of the mineral gypsum (calcium sulfate). Marble, especially white marble, is mainly calcite (calcium carbonate). They are both metamorphic rocks, formed geologically under high pressure and temperature. Alabaster is also sometimes confused with steatite (soapstone), another soft, easily polished stone. Steatite is comprised of the mineral talc, which is even softer than alabaster. Most alabaster objects are found indoors, due to their vulnerability to moisture. These pieces are generally finely carved, smoothly polished, and are often painted and decorated with gilding.
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