Plaster

About

Plaster is mixed from powder and water and sets hard. Gypsum plaster, often called plaster of Paris, sets fast and takes crisp impressions, which makes it the standard material for moulds and casts; lime plaster cures slowly and was used for walls and fresco.

Sculptors have relied on it for centuries as a working stage. Clay models were cast in plaster before being translated into marble or bronze, and the collection of Antonio Canova's full-size plaster models survives at Possagno. Carved and moulded stucco shaped the walls of the Alhambra and the ceilings of Baroque and Rococo interiors. Modern artists also valued plaster as a finished material: Alberto Giacometti built up figures in it, and in the 1960s George Segal wrapped living people in plaster-soaked bandages to make pale, anonymous figures. Look for chalky white surfaces, casting seams and small metal pins marking measuring points.