In this amazing close-up by Olivier Grunewald, we see molten sulfur burning atop a solid sulfur deposit. The picture was taken at the sulfur mine located in the crater of the Kawah Ijen volcano in East Java, Indonesia.

The miners of the 2,600 meter tall (8,660ft) Kawah Ijen volcano trek up to the crater, then down to the shore of a 200-meter-deep crater lake of sulfuric acid, where they retrieve heavy chunks of pure sulfur to carry back to a weighing station. Be sure to check out The Big Picture for an entire gallery of these miners working under the light of the moon.