The Ijen volcano is located on East Java, Indonesia.
An active vent at the edge of the lake is a source of elemental sulfur, and supports a mining operation. Escaping volcanic gases are channeled through a network of ceramic pipes, resulting in condensation of molten sulfur.
The sulfur, which is deep red in colour when molten, pours slowly from the ends of these pipes and pools on the ground, turning bright yellow as it cools. The miners break the cooled material into large pieces and carry it away in baskets. Miners carry loads ranging from 75 to 90 kilograms (165 to 198 lb), up 300 metres (980 ft) to the crater rim, with a gradient of 45 to 60 degrees and then 3 kilometres (1.9 mi) down the mountain for weighing. Most miners make this journey twice a day.
A nearby sulfur refinery pays the miners by the weight of sulfur transported; as of September 2010, the typical daily earnings were equivalent to approximately $13 US. The miners often receive insufficient protection while working around the volcano and complain of numerous respiratory afflictions. There are 200 miners.