Bone China v Porcelain

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. Developed by English potter Josiah Spode, bone china is known for its high levels of whiteness and translucency, and very high mechanical strength and chip resistance. Its high strength allows it to be produced in thinner cross-sections than other types of porcelain.

From its initial development and up to the later part of the twentieth century, bone china was almost exclusively an English product, with production being effectively localised in Stoke-on-Trent. Most major English firms made it, including Mintons, Coalport, Davenport, Royal Crown Derby, Royal Doulton, Hereford Fine China, Wedgwood and Royal Worcester.

The production of bone china is similar to porcelain, except more care is needed because of its lower plasticity and a narrower verification range. The traditional formulation for bone china is about 25% kaolin, 25% Cornish stone and 50% bone ash. The bone ash that is used in bone china is made from cattle bones that have a lower iron content. These bones are crushed before being degelatinised and then calcined at up to 1250°C to produce bone ash. The ash is milled to a fine particle size.  The kaolin component of the body is needed to give the unfired body plasticity which allows articles to be shaped. This mixture is then fired at around 1200°C.  The raw materials for bone china are comparatively expensive, and the production is labor-intensive, which is why bone china maintains a luxury status and high pricing.

Porcelain (also known as china or fine china) is a ceramic material made by heating materials, generally including clay in the form of kaolin, in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). The toughness, strength, and translucence of porcelain arises mainly from the formation of glass and the mineral mullite within the fired body at these high temperatures.

Porcelain derives its present name from the old Italian porcellana (cowrie shell) because of its resemblance to the translucent surface of the shell. Porcelain can informally be referred to as "china" or "fine china" in some English-speaking countries, as China was the birthplace of porcelain making. Properties associated with porcelain include low permeability and elasticity; considerable strength, hardness, toughness, whiteness, translucency and resonance; and a high resistance to chemical attack and thermal shock.

  The most common uses of porcelain are for utilitarian wares and artistic objects. It can be difficult to distinguish between stoneware and porcelain because this depends upon how the terms are defined. A useful working definition of porcelain might include a broad range of ceramic wares, including some that could be classified as a stoneware. Porcelain is used to make household wares, decorative items and objects of fine art amongst other things.