The name given to true porcelain. The two most important ingredients are kaolin (china clay) and petuntse (china stone) which, when fired to a high temperature (1250 to 1350 degrees celsius), fuse to a glassy matrix, forming a hard, white, translucent body. It is usually covered with a glaze made from powdered feldspar before firing. Hard-paste porcelain was first made in China, where both ingredients were available. Kaolin was only discovered in Europe at the beginning of the 18th century and the first hard-paste porcelain was made by Johann Friedrich Böttger at Meissen in 1709. In England, after the discovery of kaolin in Cornwall, hard-paste was produced in Plymouth from 1768 until 1770.