Bone ash is a white material produced by the calcination of bones. Typical bone ash consists of about 55.82% calcium oxide, 42.39% phosphorus pentoxide, and 1.79% water. The exact composition of these compounds varies depending upon the type of bones being used, but generally the formula for bone ash is Ca5(OH)(PO4)3. Bone ash usually has a density around 3.10 g/mL and a melting point of 1670 °C (3038 °F). Most bones retain their cellular structure through calcination.

Bone china is a type of vitreous, translucent pottery, the raw materials for which include bone ash, feldspathic material and kaolin. It has been defined as "ware with a translucent body". Different countries have set different standards for calling a product "bone china", based on the minimum percentage of phosphate derived from calcined animal bone or calcium phosphate that is required. This may range from 25% (USA), to 30% (UK), to 36% (China). Bone china is amongst the strongest of whiteware ceramics, 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 whiteware. Like stoneware, it is vitrified, but is translucent due to differing mineral properties.