Photojournalists Tommy Trenchard and Aurélie Marrier d’Unienville were traveling across Asia on their honeymoon when they met a few miners who worked in a sulfur mine in eastern Java, Indonesia. Intrigued, they decided to explore the mine. Trenchard said:

“We were drawn to this particular story in part because of the otherworldly visuals up there in the crater, especially the colors, and also because of the incredible human struggle of the miners who climb up there every day at great personal cost in order to support their families.”

The sulfur mine is located in a beautiful and treacherous place: the Kawah Ijen volcano. To get to the sulfur, miners must climb the side of the volcano and descend into the crater, near a stunning lake filled with turquoise water. According to Geology.com, the sulfur comes from sulfur-laden gases from fumaroles near the lake. If conditions allow, the sulfur gas condenses and then solidifies into the chunks the miners are looking for.

According to Trenchard, over 200 miners trek to the sulfur mine every day. After filling baskets with hundreds of pounds of the yellow substance, the miners climb out of the crater to sell their day’s haul. The sulfur is sold to be processed locally to make things such as sugar, fireworks, matches and even cosmetics. Trenchard said that all of this grueling work can earn the miners about $12 a day.

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