Plaster of Paris

Plaster of Paris is a quick-setting gypsum plaster comprising a finely ground white powder, which solidifies when mixed with water.

Plaster of Paris is renowned for its minimal tendency to shrink or crack upon drying, making it an ideal medium for crafting moulds. It is widely employed for precasting and securing components of decorative plasterwork, commonly found on ceilings and cornices. Additionally, in the field of medicine, plaster of Paris is used to create casts that immobilise fractured bones during the healing process, although modern orthopaedic casts often use materials like fibreglass or thermoplastics.

Sculptors often choose to work directly with plaster of Paris due to its rapid setting time, providing a sense of immediacy and allowing the artist to swiftly realise their original concept. In historical contexts, such as mediaeval and Renaissance periods, gesso — typically composed of plaster of Paris mixed with glue — was applied to surfaces like wood panels, plaster, stone, or canvas to serve as a base for tempera and oil paintings.