anthracite

ash

black

bulk

burning

business

centralheating

china

coal

coalindustry

cost

dark

dirt

dirty

effect

energy

environment

exploitation

extract

extraction

flame

fuel

gas

global

heat

import

industry

lignite

manufacturing

material

metallurgical

mine

miner

mineral

nature

pictures

poverty

power

prices

resources

smoke

stone

texture

textured

tiled

types

usesof

worker