Giant 11 metre gypsum crystals
These giant gypsum (hydrated calcium sulphate) crystals in the “Cave of Crystals” in the Naica mine, Chihuahua, Mexico pose an interesting problem: how are they formed. A Spanish-Mexican team led by Prof García-Ruiz et al. propose that these crystals are derived from "a self-feeding mechanism driven by a solution-mediated, anhydrite-gypsum phase transition". The solution from which the crystals grew were maintained in a very narrow, stable temperature range. It seems likely that related features will be discovered in the future.1
See Geology: April, 2007, v. 35, no. 4, where the crystals are featured on the cover.
- 1. Formation of natural gypsum megacrystals in Naica, Mexico,
, Geology, 2007, Volume 35, Issue 4, p.327, (2007)