Item #: CH-BA
Priced per pound.
Real bone ash is created by heating, or calcining bone, followed by cooling and milling into a fine powder. Because calcined bone has certain properties that are difficult to syntehtically recreate, the material is still manufactured. In ceramics, bone ash (Ca3(PO4)2-HT) is an important source of calcium phosphate. The calcium acts as a flux, while the phosphorous acts as a glass former. When added to a clay body such as bone china, bone ash lowers the maturing temperature and adds translucency.
Bone ash may also be used to give texture in low fire glazes. In low-fire glazes, bone ash acts as an opacifier, while in high-fire glazes it can create translucence. You may find that it is rarely used in glaze recipes; this may be because bone ash can have a tendency to cause the glaze matrix to thicken, or materials within it to flocculate, or clump together. If you mix a glaze containing bone ash, it is recommended that you use a little bit of deflocculant, such as Darvan 7.