Inside the dark, dirty way the world gets one of its biggest fuel sources

Global use of coal has fallen significantly in recent years, declining 2.3% to 4.6% through the first nine months of 2015 compared to the previous year, a decrease equal to as much as 180 million tons of standard coal, according to Bloomberg.

But coal remains widely used. And as long as it is relied upon for energy, it will have to be ripped from the earth.

From China to West Virginia, here are 15 images from coal mines around the world.