Bone ash

Bone ash is a white material made when bones are heated to very high temperatures, a process called calcination. It is mostly made of calcium oxide, phosphorus pentoxide, and a little water. The mix can change a bit depending on the bones used, but it usually follows the formula Ca₅(OH)(PO₄)₃.

This material is very heavy, about 3.10 grams for every milliliter, and it can melt at very high temperatures around 1670 °C, which is 3038 °F. Even when heated, most bones still look like bones, so bone ash is both interesting and useful in many different ways.

History

Antiquity

Burnt bones have been found at many ancient Greek places of worship. These bones are often white or bluish, which helps scientists recognize them. At a place of worship for Artemis in Eretria, a round altar made of stones was found. Animal bones were burned on this altar and then swept away. Some believe these altars were used for special rituals, but this is not certain. A writer named Xenocrates of Aphrodisias wrote that burnt bones were sometimes used in medicine, though laws in the Roman Empire stopped some practices.

Uses

Bone ash is an important material used to make bone china, a special kind of pottery. It is mixed with other materials and heated to create strong, beautiful dishes. Before it is used, bones are cleaned, heated to remove natural parts, and ground into a fine powder.

Bone ash can also help plants grow. It can be used directly as a natural plant food or changed with a special liquid to make it even better for plants. In factories, bone ash is used to protect tools and fill small cracks when working with hot metals. It stays strong even at very high temperatures and is easy to use. It is also used to help separate valuable metals like gold and silver from other materials.

Analysis of bone ash

The article looks at bone ash using a special method called X-ray fluorescence. It shows the results for three samples of bone ash used in ceramics.

In culture

Bone ash was used in special ways a long time ago. In old writings from the Book of Amos, it talks about burning bones to make a substance called lime. People used bone ash in old recipes for white paint and beauty products. It helped in a process called cupellation to separate silver from lead.