I am currently using natural charcoal, and various wood pieces. (fieryfoodscentral.com)
Untitled (Lying Pose), from Iggy Pop Life Class by Jeremy Deller, 2016; natural charcoal with white chalk on pink paper; 12 3/4 x 19 in. (dailyserving.com)
Simply heat a piece of charcoal, preferably natural charcoal, directly over a flame until it's bright red and transfer it to small metal tin that you place in the center of a saucepan filled with the puréed eggplant. (phamfatale.com)