Dirt in a 57-Across (4)
I believe the answer is:
soot
(Other definitions for soot that I've seen before include "Carbon deposit from burning" , "Chimney coating" , "Stuff from chimneys" , "Carbon black" , "Residue from burning" .)
I believe the answer is:
soot
(Other definitions for soot that I've seen before include "Carbon deposit from burning" , "Chimney coating" , "Stuff from chimneys" , "Carbon black" , "Residue from burning" .)