TYPES OF WARES
Pottery comprises three
distinctive types of wares. The first type, earthenware, has been made
following virtually the same techniques since ancient times; only in
the modern era has mass production brought changes in materials and
methods. Earthenware is basically composed of clay--often blended
clays--and baked hard, the degree of hardness depending on the
intensity of the heat. After the invention of glazing, earthenwares
were coated with glaze to render them waterproof; sometimes glaze was
applied decoratively. It was found that, when fired at great heat, the
clay body became nonporous. This second type of pottery, called
stoneware, came to be preferred for domestic use.
The third type of pottery is a Chinese invention that appeared when
feldspathic material in a fusible state was incorporated in a stoneware
composition. The ancient Chinese called decayed feldspar kaolin
(meaning "high place," where it was originally found); this substance
is known in the West as china clay. Petuntse, or china stone, a less
decayed, more fusible feldspathic material, was also used in Chinese
porcelain; it forms a white cement that binds together the particles of
less fusible kaolin. Significantly, the Chinese have never felt that
high-quality porcelain must be either translucent or white. Two types
of porcelain evolved: "true" porcelain, consisting of a kaolin
hard-paste body, extremely glassy and smooth, produced by high
temperature firing, and soft porcelain, invariably translucent and lead
glazed, produced from a composition of ground glass and other
ingredients including white clay and fired at a low temperature. The
latter was widely produced by 18th-century European potters.
It is believed that porcelain was first made by Chinese potters toward the end of the Han period (206 BC-AD 220), when pottery generally became more refined in body, form, and decoration. The Chinese made early vitreous wares (protoporcelain) before they developed their white vitreous ware (true porcelain) that was later so much admired by Europeans.
Regardless of time or place, basic pottery techniques have varied little except in ancient America, where the potter's wheel was unknown. Among the requisites of success are correct composition of the clay body by using balanced materials; skill in shaping the wet clay on the wheel or pressing it into molds; and, most important, firing at the correct temperature. The last operation depends vitally on the experience, judgment, and technical skill of the potter.
French Pottery
