background
black
burning
carbon
central
charcoal
coal
cube
dark
deep
deposits
digging
dirty
ecology
effect
energy
exploitation
extract
extraction
fossil
fuel
heat
heating
heavy
hold
hot
human
import
industry
lignite
manufacturing
material
metallurgical
mine
miner
mineral
power
resources
smoke
solid
stone
stove
texture
unclean
underground
wood
work
worker