In a volcano Idgen, which situated in the town of East Java, on the height about 2600 meters Indonesian miners manually extract the mineral deposit named sulfur. It's production occurs on the caldera which surrounds the crater. Volcano has large activity that's why it's cracks constantly emit sulfuric vapour.
Through pipes that are specifically target for the vapour, sulfur flows along the slopes of the crater and hardens. That technology doesn't require much effort or imagination, but is very effective. After end of vapour transition from gaseous to solid state, workers break the obtained stones. The tools are used by local miners are generally fittings and hammers.
To bring sulfur into receiving center, workers have to walk about 2,500 meters, carrying on their shoulders 49-95 pounds of stones. As usual workers cannot make more than 4 walks a day, so eventually their everyday salary is about 10-20 dollars. Workers don't have any safety devices, all they have is shawls for salvation of the heat. Respirators, masks and another safety equipment are available only for firefighters that extinguish the sulfur.
Miners of Cava Idgen work on rotational basis – fifteen days after fifteen. Carriers and miners work is very difficult but well-paid, and besides of all they can take a piece of sulfur that will be a good souvenir for tourists. To earn some money workers often smelts various figurines from sulfur and sell it as souvenirs. Extracted sulfur is adapted for different areas of industry: it can be vulcanization of rubber or, for example, sugar discoloration.
In addition to sulfur in the volcano are located another mineral deposits like ferromanganese that also can be used for industry. There is also a lake in the crater of volcano which fills itself with solutions of sulfuric acid and hydrogen chloride, reaching a temperature of 33 degrees Celcius.