porcelain [Ital. porcellana], white, hard, permanent, nonporous pottery
having translucence which is resonant when struck. Porcelain was first
made by the Chinese to
withstand the great heat generated in certain parts of their kilns. The
two natural substances used were kaolin, also known as china clay, a
white clay free of impurities that
melts only at very high temperature, and a feldspar mineral called
petuntse that forms a glassy cement, binding the vessel permanently.
Although proto-porcelain wares
exist dating from the Shang, by the Eastern Han high firing glazed
ceramic wares had developed into porcelain, and porcelain manufactured
during the T'ang period (618-
906) was exported to the Islamic world where it was highly prized. The
ware was refined during the Sung period (960-1279). During the Yuan
period (1280-1368), blue
and white ware was produced by utilizing cobalt blue from the Middle
East. The Ming period (1368-1644) developed this blue and white ware
but used other colors as well.
The Ch'ing period (1644-1912) designed porcelain especially for
export often utilizing Western designs. In Europe porcelain was first
commercially produced (1710) in
Meissen, Germany. Most of the European porcelain is soft paste (made
from clay and an artificial compound such as ground glass) and is not
as strong as the Chinese
hard-paste porcelain. Important European centers for porcelain are Bow,
Chelsea, Worcester, Staffordshire, Vienna, Meissen, Sèvres, Limoges,
and Rouen.

History, the beginning of Porcelain...

Jingdezhen, under a variety of names, has been central to porcelain
production in China since at least the early Han Dynasty. Earliest
techniques were very primitive, barely
above the level of standard pottery. By the time of the Southern and
Northern Dynasty period, however, techniques and materials had been
improved to the point that
Jingdezhen clay was refined into porcelain.

The Sui and Tang Dynasties introduced high-temperature kilns, resulting
in pure, translucent whites, attractive to the eye, as well as a
variety of advanced glazing
techniques. These improvements produced smooth, durable porcelain ware.
The resulting product was often referred to as "false jade".

Techniques of Porcelain...

The most noticeable difference between porcelain and the other pottery
clays is that it 'wets' very quickly (that is, added water has a
noticeably greater effect on the plasticity
for porcelain than other clays), and that it tends to continue to
'move' for longer than other clays, requiring experience in handling to
attain optimum results.

Porcelain clays can be chemically formulated for strength, plasticity
and durability to the point that they can be used as throwing bodies.
Porcelain ware was produced on
the potter's wheel in many historic cultures, including China and
Japan. Many categories of glazes, e.g. celedons, were formulated
specifically for their striking effects on
porcelain. Modern potters also produce porcelain ware, and generally
believe these clay bodies challenge production, firing and glazing
skills. Commercially formulated
procelain bodies are generally available through most clay
distributers.

Porcelain ware of all types is typically biscuit fired at around 1000
degrees Celsius (1800 degrees Fahrenheit), and glaze fired (the final
firing) at 1300°C (2300°F) or higher.