🇲🇽NAICA CRYSTAL CAVE

 27°51'03.07"N 105°29'47.05"W

(from Wikimedia Commons)

   Buried a good thousand meters below the Naica mountain in the Mexican province of Chihuahua, the cave of crystals is a chef d'oeuvre built by geology. This cavity contains some of the world's largest natural stones, measuring up to 10 meters (34 feet) and weighing up to 55 tons; and indeed some of the most beautiful ones. However, along with this shining beauty, the spot is inhospitable for human living due to extreme high temperatures and a humidity rounding the 100% ---yet, science has localized a bunch of microbial residents...

   Many hundreds of thousands years ago, the Naica crystal cave was just an ordinary limestone tunnel. Although, eventually, an underground magma chamber would heat up the groundwater, sending it upwards into this cavity. Furthermore, this water hosted the intruding anhydrite, a mineral that only remains stable in really scorching temperatures ---not even Naica's extreme heat was enough! Therefore, the material dissolved and mixed up with calcium and sulfate, giving place to gypsum; a solid element that can take the shape of the majestic crystals.

   Later, already in the mid 19th century, this area would begin to be exploited thanks to a group of prospectors who found out that the Naica mountain had a big amount of gold, silver and zinc resources. The mining had just started when, suddenly, some workers stumbled upon a cave with similar characteristics to today's protagonist. Designated as "Cave of Swords", it lays just upon his younger brother and has smaller crystals, but in a larger total. We'd have to wait until the year 2000, when the proper Naica crystal cave was uncovered, again, by accident.

Cave of Swords (from Yahoo)

   During the time of the discovery, the commanding Peñoles Mining Company was pumping out water of the caves to prevent the flooding or collapsing of mining galleries. This process drained, between others, the still unknown chamber with the crystals. Now it was just a question of time until workers would break through the thick surrounding walls. The jackpot was won by two brothers, who immediately spread the news of their exploration.

   What followed were multiple scientific surveys, still, the most eye-opening one was made in 2008. A group led by astrobiologist Penelope Boston noticed a new type of organisms in fluid samples they captured from the shining crystal grotto. These have been populating the place for thousands of years and are very much alike to other microbes found in volcanoes or hot springs, all the same, they are genetically distinct from any other lifeform on Earth. Sadly however, scientists are concerned: the organisms have been dormant for thousands of years. This is a common process many microbes do for surviving extreme conditions during centuries, such as the cave's heat in this case; yet, there comes a point when they finally die. Therefore, these microorganisms are currently under research, with experts trying to do everything possible to "wake them up". 

   Lastly, don't plan a trip here; the proper cave is no longer accessible. After mining ended, the Peñoles Mining Company stopped draining it, leaving the cave flooded again. Even if it can sound disappointing, this actually helps the crystals to reconstruct: after having been 20 years exposed into air and showing signs of disintegration, staying on water will assure them a re-growing. Who knows, maybe one day someone stumbles upon it again...

(from Click Orlando)

Sources: National Geographic (1) and (2), How Stuff Works, Click Orlando