Laying 900 feets below the surface of the Earth is the The Crystal Cave of Giants. It was found accidentally in 2000 by miners working in the silver and lead mine at Naica, Mexico. Crystal Cave is known for its large limpids, the largest crystals are over 11 meters long (36 feet) and weigh 55 tons which is the biggest figure known in the world, by far.
These crystals formed over a interval of about half a million years in a hot water solution, saturated with minerals. And the temperature stays very hot because of its nearness to a magma chamber, deep underground.
The Cave of Crystal’s floor is covered with thoroughly-faceted pellucid with huge crystal beams stick out from both the blocks and the floor. The cave is actually a horseshoe shaped hole in limestone rock.
These caves are approachable because there are continuous pumping operations by mining company’s which keep them clear of water.