09 Alabaster

Gypsum uses include: manufacture of wallboard, cement, plaster of Paris, soil conditioning, a hardening retarder in Portland cement. Varieties of gypsum known as "satin spar" and "alabaster" are used for a variety of ornamental purposes, however their low hardness limits their durability.

Alabaster is the stone of art par excellence, a much-appreciated resource for sculptors and architects who, from antiquity until these days, have been able to take advantage of its characteristic features, above all the ease with which it can be worked and polished and its translucency, a property as rare among rocks as effective in magnifying their natural beauty.

“Alabastron” was the name of a village in Old Egypt, located near the city of Thebes, in which a calcareous-type translucent stone was extracted. It seems that the term also referred to objects (e.g. vessels, cups) originating from that place, which, originally, were made with this material.

Eventually, the term, alabaster, began to refer only to the white translucent rock used in art and in the manufacturing of muchappreciated vessels.

Today, the term alabasterr efers to a massive, competent, translucent gypsum variety, with very low porosity and displaying very light colours. It consists of microcrystalline gypsum aggregates, with sizes ranging from 10 to 80 micrometres, which form an irregular mosaic. Aggregates of finest grain size are the best quality and most translucent. Impurities among the aggregates, above all clays and other salts that could have accumulated with the gypsum, are common and can colour and pattern the set.