It's a secret spot you have to see to believe - and 60 Minutes was allowed a rare look inside the incredible giant crystal cave at the centre of the earth.
The Cave of Crystals (Cueva de los Cristales), located in Naica, Chihuahua, Mexico is known for its massive selenite crystals, some of the largest natural crystals ever found. The cave is part of the Naica Mine and is situated about 300 meters (980 feet) deep
