Alabaster

A modern uplighter lamp made from Italian alabaster (white and brown types). The base is 5 inches (13 cm) in diameter

Alabaster vase of Tutankhamun

Alabaster is a name applied to varieties of two distinct minerals. Gypsum is a hydrous sulfate of calcium, and calcite is a carbonate of calcium. Gypsum is the alabaster of the present day; calcite is generally the alabaster of the ancients. Both are easy to work. They are attractive to look at. Both have been used for making a variety of artworks and objects, especially small carvings.

The two kinds are easy to tell apart. One is harder than the other. Calcite is hard (Mohs hardness 3). Gypsum is soft (Mohs hardness 1.5 to 2). It can be easily scratched by a fingernail. Also, calcite effervesces when it is treated with hydrochloric acid. Gypsum does not.

Alabaster Media

Calcite alabaster: The tomb of Tutankhamun (d. 1323 BC) contained a practical objet d’art, a cosmetics jar made of Egyptian alabaster, which features a lid surmounted by a lioness (goddess Bast).
Alabaster artefact: A composite bust of Septimius Severus; the head is marble and the bust is alabaster.
Alabaster windows in the Church of Santa Maria la Mayor of Morella, Spain (built 13th-16th centuries)
Alabaster workshop in Volterra, Italy
Calcite dish from the Ancient Egyptian tomb of "U", Semerkhet
Wounded lion, detail from the Lion Hunt of Ashurbanipal, 7th century BC, British Museum
Attributed to Willem van den Broecke, Rijksmuseum

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