These crystals are chambers in the Naica Mine in Chihuahua, Mexico, discovered in 2000 in a lead mine.
- They are made of a kind of gypsum, the same material as in dry wall.
- The chambers are along a fault line with magma heating them up to 150 F.
- The largest crystal is 36 ft long, (11 m), 13 ft wide (4m) and weighs 55 tons.
- The gypsum is so soft it can easily be scratched and damaged by tool, boots, even a fingernail.
- The chambers are 1200 feet below the surface.
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