To celebrate his wife’s birthday last year, Canadian photographer Larry Louie took her to a sulfur mine. That wasn’t the plan—their original itinerary was in Bali. But after a couple of days in that tourist-plagued paradise, they began looking for something a little less commercialized. A bit of online research led Louie to the sulfur mines of the dormant Mt. Ijen on the nearby island of Java. Famous for their electric-blue fire (created by the spontaneous combustion of subterranean gasses) and toxic yellow smoke, the mines would make an interesting photography project, Louie thought.

His wife agreed, so the couple packed their bags, booked a flight to Java, and hired a local guide to take them to the sulfur mine. They started climbing Mt. Ijen in the middle of the night and reached the summit just before dawn in order to see the blue flames. As the sun rose, they descended into the vast volcanic caldera, which emits billowing clouds of sulfur from hundreds of cracks in the earth. Ceramic pipes placed by miners in the caldera floor direct some of the smoke toward collection points, where the superheated gas instantly turns into a solid, forming dripping yellow stalactites.

These stalactites are what the workers mine. Using picks, they chip off chunks of sulfur, place them in reed baskets, and carry them up to the top of the crater, where they are loaded into wheelbarrows for the trip down the mountain. (Sulfur is used in cosmetics, explosives, and agricultural products.) Louie learned from his guide that workers spend 12-hour shifts dodging plumes of poisonous smoke (with many protected only by rags tied around their mouths) while carrying up to 180 pounds of sulfur on their backs. With temperatures reaching 100 degrees Fahrenheit and a pervasive smell of rotten eggs, it’s one of the most dangerous and unpleasant jobs on earth—but pays $12 a day, a relatively high salary for that part of Indonesia.

Louie’s guide provided him and his wife with gas masks, but they were too clogged to be useful. This became a problem when Louie insisted on getting as close as possible to his subjects. After three hours of shooting, he nearly passed out from all the toxic smoke. “I got a little dizzy and was losing my eyesight a little bit,” he says. “Fortunately my wife saw me and she yelled to the guide to get me out of there.” They eventually made the decision to end the expedition early and descend the mountain. Louie had hoped to return the next day to shoot more photographs, but he felt too sick to make another climb.

Louie has photographed people working in some of the world’s most extreme environments, including a Bangledeshi garbage dump, an Indian jute mill, and a Moroccan tannery. But few workers labor under conditions as difficult as the sulfur miners on Mt. Ijen. “I’ve always been interested in highlighting the strength of people and the struggles of workers around the world,” he says.

He’d like to return to Mt. Ijen someday—but this time, perhaps, with a functioning gas mask.

Images from the series “Devil’s Gold” are included in Louie’s book Beyond the Darkness, which was shortlisted for the 2019 Lucie Photo Book Prize.

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