from cracks at temperatures up to . The flames can be up to high; some of the gas condenses to liquid and is still ignited. Ijen is the largest blue flame area in the world. Local people refer to it as Api Biru (Blue Fire). The other location at which blue fire can be seen is in Dallol mountain, Ethiopia. Sulfur mining at Ijen 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 up to the crater rim, with a gradient of 45 to 60 degrees, and then 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, who extract 14 tons per day — about 20% of the continuous daily deposit. Media Ijen and its sulfur mining was featured in the 1991 IMAX film Ring of Fire, and as a topic on the 5th episode of the BBC television documentary Human Planet. In the documentary film War Photographer, journalist James Nachtwey visits Ijen and struggles with noxious fumes while trying to photograph workers. Michael Glawogger's film Workingman's Death is about sulfur workers. Gallery See also List of volcanoes in Indonesia Mazuku References External links Ijen Gallery Volcanological Survey of Indonesia Official website of Indonesian volcanoes at USGS The Adventures Behind Filming Ring of Fire Large photogallery from Kawah Ijen Sulfur mining in Kawah Ijen (The Big Picture photo gallery at Boston.com) More sulfur mining pictures at Ijen Spectacular Neon Blue Lava Pours From Indonesia's Kawah Ijen Volcano At Night (PHOTOS) Active volcanoes of Indonesia Volcanic crater lakes Mountains of East Java Stratovolcanoes of Indonesia Subduction volcanoes Sulfur mines Volcanoes of East Java Holocene stratovolcanoes