thumb|An example of fusain, charcoal that has been fossilized, found at a spoil pile from an underground coal mine in Grundy County, Illinois, US
thumb|An example of fusain, charcoal that has been fossilized, found at a spoil pile from an underground coal mine in Grundy County, Illinois, US
Fusain is a fossilised carbon deposit which, after some controversy, has been identified as fossilised charcoal.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).