Bone ash is a key raw material for bone china. Constituting around 50% of the body, it reacts with other raw materials in the body during firing to form, amongst other phases, anorthite.
In preparation for use in bone china, bones undergo multiple processing stages, including:
* Removal of any meat before being degreased.
* Calcination to around 1000 °C (1832 °F). This will remove all organic, and the bone is left sterilised.
* Being ground with water to fine particle size.
* Being partially dewatered.
Since the 1990s, the use of synthetic alternatives to bone ash, which are based on dicalcium phosphate and tricalcium phosphate, has increased. Significant amounts of bone china is produced using these synthetic alternatives rather than bone ash.