terracotta

Terracotta, terra cotta, or terra-cotta (; ; ), in its material sense as an earthenware substrate, is a clay-based unglazed or glazed ceramic where the fired body is porous.

In applied art, craft, construction, and architecture, terracotta is the term normally used for sculpture made in earthenware and also for various practical uses, including vessels (notably flower pots), water and waste water pipes, roofing tiles, bricks, and surface embellishment in building construction. The term is also used to refer to the natural brownish orange color of most terracotta.

In archaeology and art history, "terracotta" is often used to describe objects such as figurines not made on a potter's wheel. Vessels and other objects that are or might be made on a wheel from the same material are called earthenware pottery; the choice of term depends on the type of object rather than the material or firing technique. Unglazed pieces, and those made for building construction and industry, are also more likely to be referred to as terracotta. Glazed terracotta for tableware, and other vessels, is called earthenware, or by a more precise term such as faience which denotes a particular type of glaze.

Glazed architectural terracotta and its unglazed version as exterior surfaces for buildings were used in East Asia for some centuries before becoming popular in the West in the 19th century. Architectural terracotta can also refer to decorated ceramic elements such as antefixes and revetments, which made a large contribution to the appearance of temples and other buildings in the classical architecture of Europe, as well as in the Ancient Near East.

This article covers the senses of terracotta as a medium in sculpture, as in the Terracotta Army and Greek terracotta figurines, and architectural decoration. East Asian and European sculpture in porcelain is not covered.

Production and properties

Terracotta is a very flexible material to sculpt. Pieces can be formed by both an "additive" technique, adding portions of clay to the growing pieces, or a "subtractive" one, carving into a solid lump with a knife or similar tool. Perhaps most common is a combination of these, building up the broad shape and then removing pieces, or adding more, to produce details.

The most common method of production is to take an appropriate refined clay, then form it to the desired shape. Alternatively it may be made with one or more moulds. After drying, it is placed in a kiln or atop combustible material in a pit, and then fired. The typical firing temperature is around , though it may be as low as in historic and archaeological examples.Grove, 1 The iron content, reacting with oxygen during firing, gives the fired body a reddish color, though the overall color varies widely across shades of yellow, orange, buff, red, "terracotta", pink, grey or brown.

A final method is to carve fired bricks or other terracotta shapes. This is less common, but features for example in the architecture of Bengal on Hindu temples and mosques.

Fired terracotta is not watertight, but surface-burnishing the body before firing can decrease its porousness and a layer of glaze can make it watertight. It is suitable for use below ground to carry pressurized water (an archaic use), for garden pots and irrigation or building decoration in many environments, and for oil containers, oil lamps, or ovens. Most other uses, such as for tableware, sanitary piping, or building decoration in freezing environments, require the material to be glazed. Terracotta, if uncracked, will ring if lightly struck.

Painted (polychrome) terracotta is typically first covered with a thin coat of gesso, then painted. It has been very widely used but the paint is only suitable for indoor positions and is much less durable than fired colors in or under a ceramic glaze. Terracotta sculpture was very rarely left in its "raw" fired state in the West until the 18th century.

In art history

Terracotta female figurines were uncovered by archaeologists in excavations of Mohenjo-daro (3000–1500 BC). Along with phallus-shaped stones, these suggest some sort of fertility cult. The Burney Relief is an outstanding terracotta plaque from Ancient Mesopotamia of about 1950 BC. In Mesoamerica, the great majority of