"World at Work" is an occasional slideshow series featuring economic events from around the world through the photography of Bloomberg News. Photographer Angel Navarrete visited an ad hoc sulfur mine at the Kawan Ijen volcano in Indonesia, where for decades men have risked their health to extract chunks of sulfur they sell to middlemen, who in turn sell them to nearby factories.

The crater floor of the volcano spews sulfur through vents at the edge of a lake of sulfuric acid. Local miners have tapped those gases with ceramic pipes to earn a living. The stone and ceramic pipes cap the fumaroles, and inside, the sulfur condenses into a molten red liquid. It drips back down and solidifies into pure sulfur that miners can break and carry in baskets 700 feet to be weighed. Some loads weigh as much 200 pounds. 

Left, a miner uses a pole to extract lumps of sulfur from the crater at the Kawan Ijen volcano in East Java in August.