do human bones turn black
Bone char (Latin: carbo animalis) is a porous, black, granular material produced by charring animal bones. Its composition varies depending on how it is made; however, it consists mainly of tricalcium phosphate (or hydroxylapatite) 57-80%, calcium carbonate 6-10% and activated carbon 7-10%. Human bone char, referred to as bone charcoal, is mentioned in Thomas Pynchon 's novel The Crying of Lot 49. 2  The bones come from US soldiers who died in combat during WWII and were buried in a lake in Italy, and the char is used for filters in cigarettes.