AP

Shortly before 2 p.m., tiny, twinkling lights become visible at the end of the long, dark tunnel on the seventh level of the Prosper-Haniel mine in Bottrop, a city in west-central Germany. The lights slowly begin to take shape, as miners with mine lamps on their white helmets make their way back to the surface. It has been a difficult shift, and the men have covered several kilometers through an intricate labyrinth of tunnels and shafts. . .