Pottery, vessels and other articles made of clay that is permanently hardened by firing in a kiln. The nature and type of pottery is determined by the composition of the clay and the way it is prepared; the temperature at which it is fired; and the glazes used. Point the stamps with the mouse index for more information.
It is distinct from porcelain in being porous and opaque; fired at a temperature lower than that required for porcelain, it does not undergo vitrification.
Porcelain, a ceramic body comprising white china clay or kaolin (aluminium silicate) and feldspathic rock or petunse (aluminium and potassium silicate) that, fired in a kiln at between 1250° and 1300° C (2282° F-2372° F), vitrifies to form a white, resonant, and translucent material of greater density and hardness than the pottery bodies, earthenware and stoneware.
It was first made by the Chinese in the 7th or 8th century AD but not in Europe until the 18th century. Source: Microsoft Encarta 96.
Actually the Europeans have partially stolen from Chinese, partly found by themselves the secrets of the porcelain fabrication.
The background comes from the souvenir booklet issued in 1990 by the Denmark Postal Administration that commemorates the 200th anniversary of the Flora Danica pottery.