炭
tàn · HSK 7
charcoal
🪵 炭 = 山 (mountain) over 灰 (ashes): what fire leaves under the hillside woodpile — charcoal
炭 tàn stacks 山 mountain above a 灰-like ash/fire base, the residue of burnt wood. Sound-alike: tàn rhymes with the tang of soot. Related to 碳 tàn (carbon), which adds the stone radical.
炭 — mountain 山 + cliff 厂 + fire 火
炭 depicts charcoal produced by burning wood from the mountainside. The top combines 山 (mountain) and 厂 (cliff/slope), suggesting the hillside source of timber, while 火 (fire) below shows the burning process. The original meaning was charcoal, later extended to coal and carbon.