The Cave of the Crystals

The Cave of the Crystals is a cave 980 ft below the surface in Naica, Chihuahua, Mexico. It is a cave with some of the largest natural crystals ever found. The cave is relatively unexplored because of its extreme conditions with air temperatures of 136 °F with 90 to 99 percent humidity. The cave is on a fault above a magma chamber which heated the groundwater over long periods of time turned the sulfide ions in the water into the crystals. Although scientists believe there may be more rooms to the chamber they are planning of sealing it and allowing the water to rise(a mining company drained the water to explore the cave) because the crystals deteriorate in air  and  further exploration would require demolishing some of the crystals.