bone char vs animal charcoal

bone char and animal charcoal both are nouns.

Word	Noun	Adjective	Verb	Adverb
bone char	Yes	No	No	No
animal charcoal	Yes	No	No	No

As nouns, bone char and animal charcoal are synonyms defined as:

bone char and animal charcoal: black substance containing char in the form of carbonized bone; used as a black pigment

Other synonyms of bone char include animal black, bone black.

bone char (noun)	animal charcoal (noun)
black substance containing char in the form of carbonized bone; used as a black pigment	black substance containing char in the form of carbonized bone; used as a black pigment