About Porcelain

Ceramics - made of the earth, shaped with water, dried in air, decorated and made durable by fire!

Porcelain - Developed by the Chinese "made as fine as glass drinking cups, the sparkle of water may be seen through it ... " wrote a 9th century traveler in Cantonese porcelain. " . . good white porcelain, with the finest glaze. . . " wrote Friedrich Bottger in 1709 as he discovered the secret of porcelain production on continental Europe. The Chinese monopoly was finally broken and the mystic behind the "white gold" was lifted. The Courts of Europe rejoiced, but it remained unobtainable to the general public until the beginning of the 19th Century. A typical recipe for porcelain is 60% china clay, 20% feldspar and 20% quartz.

Bone China - In the UK the white ashes of animal bones were ground and added to porcelain from 1748 to add strength and whiteness. By the turn of the 19th century this became the standard English body. Fine bone china is translucent, wear and stain resistant but less able to withstand thermal shock compared to pure porcelain. Animal bones have been superceded with synthetic materials. A typical composition for bone-china is 25% china clay, 25% feldspar, 50% bone ash.

Bisque or Biscuit - Porcelain which after the initial firing or "biscuit firing" becomes "biscuit ware" and remains unglazed. The finish has been used on porcelain as a medium for figurines, busts and relief work and was first used in the mid-eighteenth century. The porcelain takes on a soft, smooth, matt appearance which lends itself well to figurines in white and may be subsequently painted and re-fired.


China Clay or Kaolin - A soft white natural clay [kaolin] used with feldspar [petuntse] to produce porcelain. It has plastic characteristics and surprisingly, is waterproof when wet and lends itself to being moulded. During firing, the water content is gradually reduced but retains its moulded shape. One of the major sources of kaolin for Europe is St.Austell in Cornwall, UK.

Feldspar - A mineral geologically belonging to the silicates. Melting at elevated temperatures it acts a flux in binding the constituents together during firing. As the temperature drops feldspar becomes a glass like material and contributes to the strength and translucent properties of porcelain.

Quartz - A silicate sand, quartz is from an abundant mineral group. Melting at elevated temperatures it reacts with feldspar to thicken the mixture and assist in the retention of moulded shapes by reducing distortion.

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