The Ijen volcano is a group of composite volcanoes in the Banyuwangi Regency of East Java, Indonesia. <br /> It is surrounded by a one-kilometer-wide turquoise lake that identified as the "largest highly acidic crater lake in the world. <br /> <br />The Ijen Volcano of Java Island brightens the night with its electric blue flames and lava, <br />The burning continues twenty-four hours a day, <br /> but it's most visible in darnkess. The flames rise up to five meters high. Locals call the caldera surrounding Ijen "Gunung Merapi" which means Mountain of Fire. <br /> <br />Why does it happen?? <br /> <br />Many scientists and photographers went to the Kawah ijen volcano to find the answer.When experimented it was found to be sulphur. <br /> <br />There are many elements which when burned gives different coloured flames. For example, copper produces a green flame, lithium and strontium a red flame, calcium an orange flame, sodium a yellow flame, and barium a pale green flame. <br /> <br />Grunewald and filmmaker Regis Etienne produced a documentary about the volcano called Kawah Ijen, the Mystery of the Blue Flames. <br /> <br />References- <br />https://interestingengineering.com/blue-lava-largest-sulfuric-acid-lake-ijen-volcano/ <br />https://en.wikipedia.org/wiki/Ijen
