At the Ijen volcano ceramic pipes tap into an active volcanic vent. The sulphur rich gases come out of the vent from a magma chamber some 20 kilometres below the surface and cool when they hit the pipes causing them to condense into a liquid and then solidify. At the time of reaching the surface the gases can be as hot as 600 degrees celcius. Ijen volcano, Indonesia, 2012. (Photo by Hugh Brown/South West News Service)
