Sulphur Mines Kawah Ijen Indonesia. In East Java, Indonesia lies Kawah Ijen volcano, 2,600 meters tall (8,660ft), topped with a large caldera and a 200-meter-deep lake of sulphuric acid. An active vent at the edge of the lake is a source of elemental sulphur, and supports a mining operation. Escaping volcanic gases are channelled through a network of ceramic pipes, resulting in condensation of molten sulphur. The sulphur, 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 cooled material is broken into large pieces the miners hack chunks off with steel bars, braving extremely dangerous gases and liquids with minimal protection. The miners often use insufficient protection while working around the volcano and are susceptible to numerous respiratory complaints. The sulphur is then carried out in baskets by the miners. Typical loads range from 60–100 kilograms, and must be carried to the crater rim approximately 200 meters above before being carried several kilometres down the mountain. Most miners make this journey twice a day. The miners are paid by a nearby sugar refinery by the weight of sulphur transported 1 kg selling for 625 Indonesian Rupiah, the typical daily earnings were equivalent to approximately € 6 to € 9. The sulphur is then used for vulcanising rubber, bleaching sugar and other industrial processes.