Work Inside an Active Volcano
Of all the workplaces I encountered during the shooting of this book, the Kawah Ijen volcano (2386 metres) on the Indonesian island of Java would surely be one of the most dramatic and confronting. Modern sulphur mining began here in 1968, although records suggest that native sulphur was first taken from the volcano for gunpowder manufacture as far back as 1786. Sulphur is extracted by the miners where molten sulphur flows from ceramic pipes. These ceramic and stone pipes have been inserted to tap active volcanic vents (called fumaroles) where volcanic gases, dense in hydrogen sulphide and sulphur dioxide, rise to the surface from a magma chamber deep below the Ijen lake.
As the gases approach the surface of the volcano, their temperature approximates 6000C. The pipes trap and force these gases to condense causing liquid sulphur to be produced when the temperature falls to around 445 degrees. As the liquid leaves the pipes it is still between 1500C and 2300C and does not solidify until it drops to 1200C.