To answer your first question: no. These aren't digitally retouched photos aimed at duping unsuspecting readers who don't know any better. This volcano really exists and the lava it produces really is bright blue (well, sort of) and the reason behind this phenomenon is far more simple than you might imagine.
As more and more people have come to hear of the legendary blue flame volcano, tourism to Indonesia's Kawah Ijen volcano has increased substantially. Seemingly everyone in the world wants to get a first hand look at the extraordinary blue lava, and rightly so! After all, it's not every day that tourists, travel journalists, and photographers get to witness an occurrence as stunningly beautiful as this. But as this story gains more traction worldwide, the burning question on everyones' minds is undeniably, "What makes the lava blue?"
Technically speaking, the color of lava can vary from volcano to volcano depending on the mineral composition of each, but the result is generally a vibrant red or orange colored lava. However, as you might remember from your high school chemistry class, certain elements burn very distinctly different colors at high temperatures. Boron, for example, produces a luminous bright green color, while lithium burns an unmistakable carmine. But can you recall which element burns a deep blue that matches the lava in this volcano? If you guessed sulfur, you're right on the money (and you obviously paid more attention in class than your friendly writer)! The heavy flow of sulfurous smog emitted from Kawah Ijen is directly responsible for the blue lava that has everyone so entranced.
Truth be told though, the lava itself is, in fact, NOT blue. The sulfur, burning at approximately 1500 degrees Fahrenheit, simply covers the sight of the otherwise reddish lava that most people have come to associate with a volcano eruption. To some, this may come as a bit of a disappointment, but it certainly doesn't make the sight of this bizarre molten Earth any less breathtaking.
Tourists who want to see the lava in person are more than welcome to make the two-hour hike to the caldera in which the occurrence is most common. We recommend taking the trip at night to enhance your experience by witnessing the stark contrast of the cyan lava against a dark background. Those with a bit more courage might also consider traversing the volcano on their own, but this is only recommended for experienced hikers.
In any case, the beauty of this unique volcano is undeniable, even from the comfort of your computer screen. Savvy travelers would be wise to witness this phenomenon in person though.