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 1,000 °C (1,830 °F), though it may be as low as 600 °C (1,112 °F) in historic and archaeological examples.[12] 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.
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