Giant crystal cave in Mexico

Imagine an otherworldly realm where clear, shimmering crystalline pillars glow in a hot and humid darkness. Cueva de los Cristales, or Cave of the Crystals, is a geologist’s dream. Located hundreds of meters underground in Naica, Mexico, the cave resembles nothing so much as an alien cathedral, with a roof propped up by huge selenite crystals.

Located right next to a mine complex, the cave was discovered in the year 2000 by a pair of miners named Eloy and Javier Delgado. It lies beneath another smaller crystal cave that was discovered in 1910. Other, similar caves are nearby: the Ice Palace, Cave of Swords, Queen’s Eye,

and Candles Cave. They, too, contain fantastic-looking crystals and mineral deposits, cooked up by a seeming magical alchemy of heat, chemistry, and geology.

Like La Cueva, these caves were discovered by local miners. The surrounding region has a very high water table, and the owners of the nearby Industrias Peñoles Naica mine had to pump out as much water as possible in order to access the mine’s silver and other minerals. ​Pumping the water from the mine had the effect of removing water from the nearby crystalline caves as well, paving the way for their discovery and scientific exploration.

This eerily beautiful crystalline cave houses a deadly environment, where the temperature never drops below 58 degrees Celsius (136 F), and the humidity hovers around 99 percent. Even dressed in protective gear, humans can withstand the dangerous conditions for only about ten minutes at a time. As a result, tourism is forbidden; only scientists have accessed the cave, with miners acting as guides.

The selenite needles require a warm, wet environment to survive, and scientists had to move quickly to study the cave while it was accessible. Microbiologists, working under stringent conditions to prevent contamination, bored into the columns to get samples of life forms that might exist in the fluids trapped inside the crystals. 

In early 2017, researchers reported finding dormant microbes inside the crystals. They had probably been trapped inside the crystals at least 10,000 years ago and possibly as long as 50,000 years ago. Some bacteria living in the cave do not match any other known life forms on the planet. 

Although the microbes were dormant when the scientists found them, the researchers were able to reanimate them in the lab to get more information about what they are and conditions in the cave when they were trapped. These “bugs” are referred to as “extremophiles” because they can exist and survive very extreme conditions of heat, humidity, and chemistry. 

Today, with the cessation of mining operations, the pumping has stopped. Reflooding has preserved the crystals for now, but it has also introduced new organisms into the chamber that are foreign to the environment.

ThoughtCo