bone ash

American  

noun

1. a white ash obtained by calcining bones, used as a fertilizer and in the making of bone china.

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bone ash British  

noun

1. the residue obtained when bones are burned in air, consisting mainly of calcium phosphate. It is used as a fertilizer and in the manufacture of bone china

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Etymology

Origin of bone ash

First recorded in 1615–25

Example Sentences

The new law will put an end to "bone ash apartments", which have risen in popularity as spaces in cemeteries remain scarce.

From BBC • Mar. 31, 2026

And speaking of bone, the English refined traditional porcelain by using crushed bone or bone ash in the clay mix for a whiter, brighter finish that we know as “bone china.”

From Seattle Times • Aug. 5, 2023

The railways transported thousands of tons of bones to the Michigan Carbon Works, in Detroit, which produced four thousand tons of bone ash and five thousand tons of bone black in one year.

From The New Yorker • May 13, 2016

The bone ash is then pressed into shape with the piston, and the cupel finished with the help of three or four smart blows from a mallet.

From A Text-book of Assaying: For the Use of Those Connected with Mines. by Beringer, Cornelius

Of these, the spent animal charcoal of the sugar-refiners, usually containing about 70 per cent of phosphates, and South American bone ash, are the most important.

From Elements of Agricultural Chemistry by Anderson, Thomas