bituminous coal
black
black gold
carbon
carbon dioxide
coal
coal pile
coal structure
combustible
dark
deposits
energy
energy source
energy storage
exploitation
extraction
flashlight
fossil
fossil fuel
fuel
glow
hard
helmet
holds
in his hands
industrial
industry
light
lump
male
mine
miner
mineral
mining
night
palms
pollution
potential
raw material
rock
shale
shines
solid
squeezes
stone
unclean
underground
wealth
work clothes
worker