Editing Plaster (section)

===Art===
{{See also|Plaster cast}}
[[File:sch op 8.jpg|thumb|Example of a stenciled plaster design]]

Mural paintings are commonly painted onto a plaster secondary support. Some, like Michelangelo's [[Sistine Chapel ceiling]], are executed in [[fresco]], meaning they are painted on a thin layer of wet plaster, called [[intonaco]]; the pigments sink into this layer so that the plaster itself becomes the medium holding them, which accounts for the excellent durability of fresco. Additional work may be added ''a secco'' on top of the dry plaster, though this is generally less durable.

Plaster (often called [[stucco]] in this context) is a far easier material for making [[relief]]s than stone or wood, and was widely used for large interior wall-reliefs in Egypt and the [[Near East]] from antiquity into Islamic times (latterly for architectural decoration, as at the [[Alhambra]]), Rome, and Europe from at least the Renaissance, as well as probably elsewhere. However, it needs very good conditions to survive long in unmaintained buildings – Roman decorative plasterwork is mainly known from [[Pompeii]] and other sites buried by ash from [[Mount Vesuvius]].

Plaster may be cast directly into a damp clay mold. In creating this ''piece molds'' (molds designed for making multiple copies) or ''waste molds'' (for single use) would be made of plaster. This "negative" image, if properly designed, may be used to produce clay productions, which when fired in a kiln become [[terra cotta]] building decorations, or these may be used to create cast [[concrete]] sculptures. If a plaster positive was desired this would be constructed or cast to form a durable image artwork. As a model for stonecutters this would be sufficient. If intended for producing a bronze casting the plaster positive could be further worked to produce smooth surfaces. An advantage of this plaster image is that it is relatively cheap; should a patron approve of the durable image and be willing to bear further expense, subsequent molds could be made for the creation of a wax image to be used in [[lost wax casting]], a far more expensive process. In lieu of producing a bronze image suitable for outdoor use the plaster image may be painted to resemble a metal image; such sculptures are suitable only for presentation in a weather-protected environment.

Plaster expands while hardening then contracts slightly just before hardening completely. This makes plaster excellent for use in molds, and it is often used as an artistic material for casting. Plaster is also commonly spread over an armature (form), made of wire mesh, cloth, or other materials; a process for adding raised details. For these processes, limestone or acrylic based plaster may be employed, known as stucco. {{Citation needed|date=October 2008}}

Products composed mainly of plaster of Paris and a small amount of [[Portland cement]] are used for casting sculptures and other art objects as well as molds. Considerably harder and stronger than straight plaster of Paris, these products are for indoor use only as they degrade in moist conditions.
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===Funeral processes===
Plaster is used by many morticians and funeral home directors to recreate destroyed tissue, reconnect severed limbs to corpses, and to fill wounds sustained during the incident that caused the death.{{cn|date=June 2022}} -->