A carved wooden Bodhisattva from the Song dynasty-garden sculpture

Ludwig Gies, cast iron plaquette, 8 x 9.8 cm, "Refugees 1914–1915"

Bronze and related copper alloys are the oldest and still the most popular metals for cast metal sculptures; a cast bronze sculpture is often called simply a "bronze". Common bronze alloys have the unusual and desirable property of expanding slightly just before they set, thus filling the finest details of a mold. Their strength and lack of brittleness (ductility) is an advantage when figures in action are to be created, especially when compared to various ceramic or stone materials (see marble sculpture for several examples). Gold is the softest and most precious metal, and very important in jewellery; with silver it is soft enough to be worked with hammers and other tools as well as cast; repoussé and chasing are among the techniques used in gold and silversmithing.

Casting is a group of manufacturing processes by which a liquid material (bronze, copper, glass, aluminum, iron) is (usually) poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solid casting is then ejected or broken out to complete the process,[9] although a final stage of "cold work" may follow on the finished cast. Casting may be used to form hot liquid metals or various materials that cold set after mixing of components (such as epoxies, concrete, plaster and clay). Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods. The oldest surviving casting is a copper Mesopotamian frog from 3200 BC.[10] Specific techniques include lost-wax casting, plaster mold casting and sand casting.

Glass

Glass may be used for sculpture through a wide range of working techniques, though the use of it for large works is a recent development. It can be carved, with considerable difficulty; the Roman Lycurgus Cup is all but unique.[11] Hot casting can be done by ladling molten glass into molds that have been created by pressing shapes into sand, carved graphite or detailed plaster/silica molds. Kiln casting glass involves heating chunks of glass in a kiln until they are liquid and flow into a waiting mold below it in the kiln. Glass can also be blown and/or hot sculpted with hand tools either as a solid mass or as part of a blown object.

A carved wooden Bodhisattva from the Song dynasty 960–1279, Shanghai Museum

Pottery

Pottery is one of the oldest materials for sculpture, as well as clay being the medium in which many sculptures cast in metal are originally modelled for casting. Sculptors often build small preliminary works called maquettes of ephemeral materials such as plaster of Paris, wax, unfired clay, or plasticine. Many cultures have produced pottery which combines a function as a vessel with a sculptural form, and small figurines have often been as popular as they are in modern Western culture. Stamps and moulds were used by most ancient civilizations, from ancient Rome and Mesopotamia to China.

Wood carving

Detail of Jesus just dead, Spanish, wood and polychrome, 1793.

Wood carving has been extremely widely practiced, but survives much less well than the other main materials, being vulnerable to decay, insect damage, and fire. It therefore forms an important hidden element in the art history of many cultures.[3] Outdoor wood sculpture does not last long in most parts of the world, so that we have little idea how the totem pole tradition developed. Many of the most important sculptures of China and Japan in particular are in wood, and the great majority of African sculpture and that of Oceania and other regions.

Wood is light, so suitable for masks and other sculpture intended to be carried, and can take very fine detail. It is also much easier to work than stone. It has been very often painted after carving, but the paint wears less well than the wood, and is often missing in surviving pieces. Painted wood is often technically described as "wood and polychrome". Typically a layer of gesso or plaster is applied to the wood, and then the paint is applied to that.