Cueva de los Cristales (Cave of Crystals)
http://news.nationalgeographic.com/news/2007/04/photogalleries/giant-crystals-cave/images/primary/crystal-cave-1.jpg
It's "the Sistine Chapel of crystals," says Juan Manuel García- Ruiz.
The geologist announced this week that he and a team of researchers have unlocked the mystery of just how the minerals in Mexico's Cueva de los Cristales (Cave of Crystals) achieved their monumental forms.
Buried a thousand feet (300 meters) below Naica mountain in the Chihuahuan Desert, the cave was discovered by two miners excavating a new tunnel for the Industrias Peñoles company in 2000.
The cave contains some of the largest natural crystals ever found: translucent gypsum beams measuring up to 36 feet (11 meters) long and weighing up to 55 tons.
"It's a natural marvel," said García-Ruiz, of the University of Granada in Spain.
To learn how the crystals grew to such gigantic sizes, García-Ruiz studied tiny pockets of fluid trapped inside.
The crystals, he said, thrived because they were submerged in mineral-rich water with a very narrow, stable temperature range-around 136 degrees Fahrenheit (58 degrees Celsius).
At this temperature the mineral anhydrite, which was abundant in the water, dissolved into gypsum, a soft mineral that can take the form of the crystals in the Naica cave.
The new findings appear in the April issue of the journal Geology.
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