Kawah Ijen—the volcano that spews blue flames

Kawah Ijen is one of several volcanoes located within the 20 km wide Ijen Caldera in East Java, Indonesia. The caldera of Kawah Ijen harbours a kilometre-wide, turquoise coloured, acidic crater lake that leaks sulphurous gases constantly. At night, the hot gases burn to emit an eerie blue glow that is unique to Kawah Ijen. The gases emerge from the cracks in the volcano at high pressure and temperature, up to 600°C, and when they come in contact with the air, they ignite, sending flames up to 16 feet high. Some of the gases condense into liquid sulphur, and continues to burn as it flows down the slopes giving the feeling of blue lava flowing.

Kawah Ijen’s sulphuric gases are also mined for sulphur. The volcanic gases are trapped by the local miners and 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 miners break the cooled material into large pieces and carry it away in baskets to a nearby refinery. A worker can earn up to $13 dollars a day in this way.
The workers work in extremely hazardous condition with insufficient protection. Most of them suffer from numerous respiratory problems due to breathing toxic fumes day in and out. At times, they work at night to escape the heat of the sun, and to earn extra income.