In 2014 Italian photojournalist Luca Catalano Gonzaga went to Indonesia and spent ten days inside what he calls “the womb” of the Kawah Ijen volcano in East Java. Here, men toil in arduous conditions to mine sulfur from the depths of the crater—effectively breaking their own bodies in the process.

In their search for “devil’s gold,” as they call it, about 300 miners make a daily climb two miles up the mountain, then head downward more than 900 yards into the volcano, where the sulfur crystals form. Most work without any protection in darkness and stifling heat—all the while breathing sulfurous gas that burns their lungs and makes tears stream from their eyes.

To retrieve the sulfur, they attack it