Kawah Ijen is one of several volcanoes situated in a 20 km radius in East Java, Indonesia. The caldera of Kawah Ijen harbors a kilometer-wide, turquoise colored, acidic crater lake that leaks sulphurous gases. 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 sulfur, 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. These pictures were captured by photographer Olivier Grunewald, who lost two lenses and a camera to sulphuric corrosion while trying to capture the ‘other-worldly’ pictures.