Earthenware Clays
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Earthenware clays were some of the earliest clays used by potters, and it is the most common type of clay found. These clays are highly plastic, or easily worked, and can be sticky. Earthenware clays contain iron and other mineral impurities which cause the clay to reach its optimum hardness at lower temperatures, between 1745 F and 2012 F (950 C and 1100 C).
Typical colors for moist earthenware clays are red, orange, yellow, and light gray. Colors for fired earthenware includes brown, red, orange, buff, medium grey, and white. Fired colors are in large part determined by the content of mineral impurities and the type of firing. Terracotta, which means quite literally “baked earth”, is one of the most popular types of earthenware.