Naica Mine

Enormous gypsum crystals in a Naica cavern, found during mining. Note person at bottom right for scale.

The Naica Mine of the Mexican state of Chihuahua, is a working mine that contains extremely large selenite crystals.[1] Located in Naica in the municipality of Saucillo, the Naica Mine is a lead, zinc and silver mine operated by Industrias Peñoles, Mexico's largest lead producer.[2] Caverns discovered during mining operations contain crystals of selenite (gypsum) as large as 1.2 m (4 ft) in diameter and 15 m (50 ft) long. Peñoles announced in October 2015 that it was indefinitely suspending operations at Naica Mine.[3]

Currently, the high temperature is 58° C (136° F) with 99% humidity, which interferes with breathing and increases the risk of asphyxiation. Because of this, researchers require specialized suits with an oxygen supply to survive working in the environment.

Cave of the Crystals

Location of the Swords and Crystal caves with the gypsum crystals within the idealized block diagram of Naica mine

The Cave of Crystals is a cave approximately 300 m (1,000 ft) below the surface in the limestone host rock of the mine. The chamber contains giant selenite crystals, some of the largest natural crystals ever found.[4][5] The selenite crystals were formed by hydrothermal fluids emanating from the magma chambers below. The cavern was discovered while the miners were drilling through a newly drained area. The caves are closed to the public, and remain closed after a worker tried to enter the cave to steal some of the selenite, only to suffocate and die in the cave's humid and inhospitable atmosphere.[6] After enough research on the crystals has been carried out, some of the chambers will be allowed to flood again and continue the process of crystal growth.

The Cave of Swords

The Cave of Swords is another chamber in the Naica Mine, also containing gypsum crystals but each "only" about a meter long, due to the fact that these crystals are younger and had been growing for much less time by the time they were discovered.[5]

See also

References

  1. ↑ García-Ruiz, Juan Manuel, 2007, Formation of natural gypsum megacrystals in Naica, Mexico, Geology, 35(4): p. 327 doi:10.1130/G23393A.1
  2. ↑ "Naica: largest lead producing mine in Mexico"
  3. ↑ "Penoles suspends operations at Naica mine in northern Mexico". Reuters. Retrieved 14 October 2015.
  4. ↑ National Geographic, 2008. Cavern of Crystal Giants
  5. 1 2 National Geographic, 2007. Giant Crystal Cave's Mystery Solved
  6. ↑ http://www.earthmagazine.org/article/danger-and-wonder-nat-geos-giant-crystal-cave

Coordinates: 27°51′3″N 105°29′47″W / 27.85083°N 105.49639°W / 27.85083; -105.49639

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.