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The massive gypsum crystals found in Mexico’s Naica mine are spectacular to behold. The meter-thick beams of translucent crystal stretch across a life-threateningly hot and humid chamber deep within a Mexican mountain.
In 2000, the so-called “Cave of Crystals” was discovered after the chamber had been pumped free of its waters for mining operations. (The chamber was actually drained in 1975, but remained unexplored until 2000.) Without the mineral-rich waters to provide material for the crystals, their growth is on hold.
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