Bone china

Bone china is a type of soft-paste porcelain that is composed of bone ash, feldspathic material, and kaolin. It has been defined as ware with a translucent body containing a minimum of 30% of phosphate derived from animal bone and calculated calcium phosphate. Bone china is the strongest of the porcelain or china ceramics, having very high mechanical strength and chip resistance, and is known for its high levels of whiteness and translucency. Its high strength allows it to be produced in thinner cross-sections than other types of porcelain. Like stoneware it is vitrified, but is translucent due to differing mineral properties.

The first commercially widespread bone china was developed by the English potter Josiah Spode in the early 1790s. From its initial development and up to the later part of the 20th century, bone china was almost exclusively an English product, with production being effectively localised in Stoke-on-Trent. Most major English firms made or still make it, including Fortnum & Mason, Mintons, Coalport, Spode, Royal Crown Derby, Royal Doulton, Wedgwood and Worcester.

In the UK, references to "china" or "porcelain" can refer to bone china, and "English porcelain" has been used as a term for it, both in the UK and around the world.

The first development of what would become known as bone china was made by Thomas Frye at his Bow porcelain factory near Bow in East London in 1748. His factory was located very close to the cattle markets and slaughterhouses of Essex, and hence easy access to animal bones. Frye used up to 45% bone ash in his formulation to create what he called "fine porcelain". Although in quality it rivalled porcelain imported from Europe and China the factory was not a commercial success.

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