Hard-paste Porcelain

Hard-paste Porcelain

Hard-paste porcelain is made from a mixture of china clay (kaolin) and china stone (petuntse). The use of china stone dispenses with the need for the 'frit' used in soft-paste porcelain.

The strength and whiteness of the porcelain was improved by ageing the paste in store.

There are three types of porcelain:

Bone china

This type of porcelain often has a grey appearance and is extremely hard, it is fired at a much higher temperature than soft-paste porcelain. The ingredients melt and fuse into a dense strong body . It will allow bright light to pass through it. Colours lie on top of the glaze

Hard-paste porcelain recipe: 50% china clay, 30% china stone, 20% flint. Firing: Biscuit temperature 900 C - 1000 C. Glost firing 1350 C - 1400 C.

Porcelaneous ware was first made in China, hence its common name china. Chinese porcelain is less vitrified (and therefore softer) than its modern European counterpart, which was developed in Germany in the early 18th century.

questions / comments? email Steve Birks steveb@netcentral.co.uk