Kowa Ijen is an active volcano on the island of Java.
Local men journey into the crater to remove lumps of sulphur rock which can weigh up to 80kg. They carry this load back up to the rim and then down to a weighing station situated roughly halfway down the volcano. Two journeys into the crater are the norm for each day. The oldest guy is 63 years of age and has been working the volcano since a young man.
After a rest the sulphur is then carried all the way down to another weighing station, then loaded onto a lorry to be taken to a refining site in the jungle where it is melted down so that some impurities can be removed. The molten sulphur is then poured onto the floor, allowed to harden, then broken up and sent to a factory for making fertiliser.
© Chris Martin