Production and Properties
An appropriate refined clay is shaped into the desired shape. After drying it is placed in a kiln, or atop combustible material in a pit, and then fired. The typical firing temperature is around 1000°C. The iron content gives the fired body a yellow, orange, red, "terracotta", pink, grey or brown color. 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 in-ground use to carry pressurized water (an archaic use), for garden ware or building decoration in tropical 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 that the material be glazed. Terracotta, if uncracked, will ring if lightly struck. Some types of terracotta are created from body that includes recycled terracotta ("grog").
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Famous quotes containing the words production and/or properties:
“From the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.”
—Charles Darwin (1809–1882)
“The reason why men enter into society, is the preservation of their property; and the end why they choose and authorize a legislative, is, that there may be laws made, and rules set, as guards and fences to the properties of all the members of the society: to limit the power, and moderate the dominion, of every part and member of the society.”
—John Locke (1632–1704)