boneblack

American  

[bohn-blak] / ˈboʊnˌblæk /

Or bone black

noun

1. a black, carbonaceous substance obtained by calcining bones in closed vessels, used as a black pigment, a decolorizing agent, etc.

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boneblack British  

/ ˈbəʊnˌblæk /

noun

1. a black residue from the destructive distillation of bones, containing about 10 per cent carbon and 80 per cent calcium phosphate, used as a decolorizing agent and pigment

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Etymology

Origin of boneblack

First recorded in 1805–15; bone ( def. ) + black

Example Sentences

Muriate of potash costs $40 and upwards per ton, sulfate about $48, dissolved boneblack about $24, ground bone about $30, kainit about $13, and nitrate of soda about 2-1/4 cents per pound.

From Manual of Gardening (Second Edition) by Bailey, L. H. (Liberty Hyde)

While they may improve conditions somewhat, the only solution to such a problem is the use of the boneblack process.

From The Philippine Agricultural Review Vol. VIII, First Quarter, 1915 No. 1 by Various