It is the raw material for plaster sculpture and statues, the main component of plasterboard, and the anchor of broken bones. Mankind has known and used this tool for thousands of years. But at the turn of the 21st century, the world was in awe when sinners discovered such huge gypsum crystals that they did not even dare to dream about.
The cave of giant crystal pillars is hidden under the Mexican Sierra de Naica mountain, at a depth of 300 meters. The pillars attached to the cave wall and floor were at least 1,500 feet high, so you could sit on them. But before you start packing your bags, let’s say that no matter how small it may seem, the cave is not open to visitors, which is to say the least: this place is a fish trap.
East side
The regional main lines pass directly below the Sierra de Naica. About 26 million years ago, magma began to push the surface of the Earth through these fault lines, which led to the formation of the mountain and was also hidden in the formation of huge crystals.
Perilous Cave is a U-shaped cave in the valley below the Sierra de Naica. The tunnel, about 30 meters long and 10 meters wide, was filled with ground water, which was forced into the hole by the magma chamber. This infiltrated water contained a substance called anhydrite.
At a temperature of 58 °C or higher, anhydrite remains stable, however, if the temperature drops below that, the clay separates from the water and gypsum forms. (This is also a reversible process).
The magma below the Riscristle Cave kept the water in the cave warm, but the water slowly dropped below 58°C. That’s when the gypsum, known as the selenite columns that can be seen above, started to grow.
Because the crystals remained underwater, and the water temperature only dropped a few degrees below 58 degrees Celsius, they were able to grow continuously.
Of course, they didn’t grow overnight: according to a 2011 study, it takes between 500,000 and 900,000 years for a 1-meter-diameter selenite crystal to form amid the conditions in the cave. Over time, many crystals of suspended size were formed. Many of them are 4 to 6 meters long, and the largest can reach 1 meter in thickness and 11 meters in length.
The first cave full of selenite crystals was discovered in 1910 by miners under the Sierra de Naica mountain, who searched for gold, tin, zinc and gold in the 19th century. The criminal company Peñoles Mining Company found a cave 120 meters below the surface, now called the Cave of Swords. However, these crystals were much smaller than the Perilous Cave, the largest of which was about 2.5 meters long.
In fact, it was formed in the same way as larger crystals were discovered later, but the water in the Cave of Swords actually died faster, which limited the growth of selenium crystals.
The Riskristly Cave itself was only found in 2000. The water was pumped at the level by the Peñoles Mining Company when we discovered that the lake was filled with huge columns of selenite.
However, it soon became apparent that the Riskristly Cave was an unfriendly place. Not only was the air temperature unbearable 47.1 degrees Celsius, but also the humidity, which was close to 100 degrees Celsius. The place was so narrow that anyone who stayed in the cave for a long time risked condensation in its waters, which could be fatal.
Source: howstuffworks
