Piles of dirt made by drilling machines. There are more than 2 million shafts that have been excavated for prospecting and the extraction of opal. (Tamara Merino)

Photographer Tamara Merino and her boyfriend were driving through the desert in Australia in November 2015 when they started to see a few odd signs: “Underground bar,” then “underground restaurant.” After they got a flat tire, they found an underground church — empty, but lit by a few flickering candles. They had stumbled into the city of Coober Pedy, a partly subterranean community and the opal capital of the world.

The town’s name comes from the Aboriginal phrase “kupa piti,” or, roughly, “white man’s hole.” After the first opal was found in the area just over 100 years ago, some of the earliest opal miners burrowed below the utterly post-apocalyptic, dust-storm-prone landscape to escape punishing temperatures.

The first person Merino met was Gabriele Gouellain, a miner from Germany who invited them into her dugout. As soon as Merino stepped inside, the scorching 117-degree heat wafted away and her eyes adjusted to the darkness. Gouellain, one of the few female miners, told them to stay as long as they wanted, so the pair bedded for the night. In the morning, they were covered in dust and dirt that had loosened from the ceiling. “I could feel the earth was alive and wanted to tell its story,” Merino said via email. Over two years, Merino spent a total of a month and a half documenting the town and its inhabitants.

Around Coober Pedy, the earth is pockmarked with evidence of drilling. Like giant anthills, piles of mullock — rock waste spit up by mining machinery — fill the horizon. Miners sift through them, and once they move on, scavengers (or tourists) can “noodle,” or search the abandoned piles hoping to come upon a gem that was missed.

Gabriele Gouellain, a German immigrant, waits in the kitchen for her husband to return from mining. Approximately 60 percent of the population of Coober Pedy lives in underground houses called “dugouts.” (Tamara Merino)

An oil painting showing the piles of dirt made by tunneling machines. The painting hangs on the wall of an underground house. (Tamara Merino)

Ex-miner Shane’s children sometimes find pieces of opal in the soil near their house “because they are closer to the ground,” their father says. (Tamara Merino)

The weather in Coober Pedy can be dry and hostile, with temperatures reaching the 110s. (Tamara Merino)

Over the years, the town attracted a motley crew that included returning World War I veterans and outlaws. Now it is a patchwork quilt of a community, boasting people from approximately 45 countries.

The town’s residents fall into several categories. Some have become rich beyond their wildest dreams, throwing huge parties and expanding their dugouts. One resident even had an indoor pool and underground beauty parlor installed, according to the Telegraph. Others made a fortune but frittered it away or never found anything again.

But for the remainder, the mines have held only false promises, never yielding treasure and slowly sapping time and energy. Coober Pedy is where “opal fever takes place,” Merino said, “[where] madness, ambition, greed, despair, distrust, crimes and obsession begin.”

An underground Orthodox Church built in 1993 by the Serbian community. Every Sunday the monk holds a service. (Tamara Merino)

Joe Rossetto, an Italian immigrant, has an underground museum with his private collection of stones, including fossils, opal and other antiques that he found in the desert around Coober Pedy. (Tamara Merino)

Trucks, cars and junk from old machinery decorate Coober Pedy’s landscape and wait to be combed for spare parts. (Tamara Merino)

Peter Broadbear searches with a black light UV light for opal pieces that miners may have left behind in the opal fields. (Tamara Merino)

Opal miners Jirayr Ayanian and Ray work with a jackhammer and a tunneling machine while searching for opal. (Tamara Merino)

Goran Dakovic, a miner from the former Yugoslavia, searches for traces of opal on the wall. He works with a circular tunneling machine to gain more access to the gemstone. (Tamara Merino)

Opal is one of the most valuable gemstones in the world. Its price varies depending on its type, color and weight. (Tamara Merino)

Jürgen Feldheim, a German miner, prepares to lower himself into a 20-meter-deep vertical shaft of an opal mine. (Tamara Merino)

An aerial view of the mining fields. Coober Pedy is the largest opal mining area in the world. (Tamara Merino)

A vertical shaft used for moving heavy machinery in and out of the mine. This type of machinery usually stays in the mine during the working period, be it days or months at a time. (Tamara Merino)

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