Sulphur miners of Mt Ijen

Acid Lake at Mt Ijen

Indonesia is a massive country and is made up of some 17000 islands. There is a tremendous diversity in culture, food and landscapes. One thing that Indonesia has a lot of, is volcanoes. The Most deadly volcanic eruption was Mt Krakatoa which erupted violently in 1888, killing some 36000 people. The son of Krakatoa is forming in the crater (underwater) left by the 1888 eruption. The last known eruption of the Son of Kratatoa was 19 February 2017. This volcano is busy building up to become another major volcano. The Son of Krakatoa is in the sea between the Islands of Java and Sumatra in the north of Indonesia. The most violent volcanic eruption in recorded history was in 1815 when Mt Tambora erupted. Indonesia has at least 127 active volcanoes. The most active of these volcanoes are Mt Kelud, which has erupted 30 in recorded history, and Mt Merapi with 80 recorded eruptions in recorded history.We are not talking about the occasional little puff, but significant eruptions.

Sulphur miner of Mt Ijen

Mt Ijen is one of the many active volcanoes in Indonesia. It can be found on the Eastern side of the Island of Java, close to Bali. The current Mt Ijen is in the 20 mile wide Ijen crater, which is evidence of violent eruptions in the past. There are two characteristics which make Mt Ijen and interesting place to visit. The first of these is a beautiful, but deadly crater lake. It is beautiful because of the unique turquoise colour of the water. It is deadly, because this is the most acidic lake in the world. It is also the world's larger highly acidic lake. The lake is basically pure sulphuric acid with a pH of 0.5! The acid which is commonly used in a swimming pool is also sulphuric acid, but this only has a pH of 2. The lake is so acidic as it is fed by hydrothermal vents filled with the gasses, mostly sulphur, from the active magma chamber below.

Where the sulphur is mined

The other interesting aspect of this volcano is the fact that these sulphur-filled gasses which constantly escape from the fumaroles from lake side solfatras. This is geology talk for "there is a constant stream of sulphur gas escaping through cracks in the rocks". The constant white "smoke" which can be seen at Mr Ijen is, in fact, the espacing sulphur rich gas. When this sulphur rich gas reaches the surface, it condenses and leaves highly purified blocks of sulphur building up at the vents. This is a valuable product and it is actively mined. The only way to mine this sulphur is for people to move down into the caldera and carry out the blocks of sulphur. There is a constant row of men moving into the crater and out again with unbelievably heavy loads of sulphur blocks in two baskets which they carry on their shoulders. Extremely labour intensive. Of course these men, with their heavy loads of pure yellow suplur make for very nice photos.

I was doing some work in Java and the final stop on the work part of my trip was in Surabaya on the eastern side of Java, relatively close to Mt Ijen and another famous volcanic sight of Mt Bromo. So, before getting my flight home, I took the weekend off to visit both Mt Ijen and Mt Bromo. I will describe my trip to Mt Bromo in a later post.

Dead trees and sulphur gas

I was staying at the   hotel in Surabaya and my tour was arranged through Sunrise Holidays (http://www.sunriseholiday.com/web/). I was picked up at my hotel (Hotel Santika Premiere Malang) and we started the drive to Mt Ijen. This was a really beautiful drive firstly along the coast line and then through the mountains and into the coffee plantations in the region. We arrived at the hotel (Catimor Homestay) were I would spend the night before visiting Mt Ijen. A really interesting area with lots of local children playing soccer. They also just loved the camera!

Pure sulphur

The next morning was an early start to Mt Ijen. From the car park, there was a fairly substantial climb up the slope of the volcano. Not long after starting the climb, the first of the early rising sulphur miners were making their way down with their load of sulphur. They normally try to get three trips up and down the mountain in a day. The guide told me not to give them money, but to give them a few cigarettes for taking photos. I guess that their lungs were, in any case,  so stuffed from the sulphur fumes, that a few smokes would not do any more damage to their lungs!

After a good long climb, I reached the rim of the volcano and got the first really good whiff of sulphur. With a slight change in wind direction, I was suddenly engulfed in a plumb of sulphur gas. This was quite a surreal experience. The sulphur clouds obvious blow over the area frequently as most of the trees on the rim were dead. The pungent smell of sulphur with the dead trees gave the area an other-worldly, almost apocalyptic appearance.

Weigh station for the sulphur

From the rim, there were beautify views into the crater where the billowing white sulphur gas could be seen. The lake was a beautiful colour and there were many sulphur miners making their way up from the mining area at the bottom of the crater. It is possible to go down into the crater. These trips normally leave very early in the morning so that you can see the blue flames of the burning sulphur gas where the sulphur deposits are being formed. Special protection is needed to go close to the sulphur deposits (although the miners have no such protection).

All in all an excellent trip and well worth the visit. From Mt Ijen I continued on my week-end trip to Mt Bromo and then on to Surabaya airport to start my flights home, first to Jakarta and then on Emirates to Johannesburg via Dubai.