bone ash

noun

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

Origin of bone ash

First recorded in 1615–25

Also called bone· earth·.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for bone ash

Historical Examples of bone ash

Formerly the test was lined with bone-ash; at present the hearth Cupelling.
Encyclopaedia Britannica, 11th Edition, Volume 16, Slice 3
Various
The floor of the muffle is protected with a layer of bone-ash, which absorbs any oxide of lead that may be accidentally spilt.
A Textbook of Assaying: For the Use of Those Connected with Mines.
Cornelius Beringer and John Jacob Beringer
The buttons are removed from the cupel with a pair of pliers and then brushed to remove adherent litharge and bone-ash.
A Textbook of Assaying: For the Use of Those Connected with Mines.
Cornelius Beringer and John Jacob Beringer
When the bone-ash has been sufficiently compressed, the die is withdrawn, and the cupel removed from the ring.
The Silversmith's Handbook
George E. Gee
Coprolites are seldom used alone for the manufacture of superphosphates, but are generally mixed with bone-ash and bone dust.
Elements of Agricultural Chemistry
Thomas Anderson

British Dictionary definitions for bone ash

bone ash

noun

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

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012