Where does “Kohle” come from?

Kohle (German) comes from Middle High German kole, from German Kohl, from Middle High German kōl, from Old High German kol, from Proto-West Germanic kol, from Proto-Germanic kulą, from Proto-Indo-European gʷol-, from Proto-Indo-European ǵwelH- — to burn; to shine.

Kohle (German): coal; a coal; a piece of coal; money; dough; dosh