africa
background
black
burning
central
charcoal
coal
cube
dark
dirty
ecology
effect
energy
environment
exploitation
extract
extraction
fire
fossil
fuel
hand
heat
hold
hot
human
industrial
industry
lignite
man
manufacturing
material
metallurgical
mine
miner
mineral
mining
nature
power
processing
production
protection
resources
rock
source
stone
top
underground
work
worker