Get a load of those huge, long shafts!

Dig in deep into the Naica Crystal Caves in Chihuahua, Mexico, and get nothing less than massive crystals sizing up to 11 meters in length, 4 meters in diameter, and 55 tons in weight.

For geologists and mineralogists, it’s a real goldmine—except it’s not really made of gold but of selenite, a rare crystallized form of gypsum. The cave conditions are extreme: it has a constant temperature of 58 degrees Celcius and very high humidity.

Trekkers are given a suit full of ice-bags with a respirator when they had to explore the cave. And they gotta move quickly because of the longer your stay in there, the more you lose your brain functions, and the more you lose your marbles, the higher the risk you lose your step and get impaled by a crystal to a slow and gruesome death.

It’s bad news for those without the icebag suits—15 minutes in, and you’re dead as a dodo. Just a warning to those sneaky crystal thieves out there.