On the Road (Europe 2010): Cardona, Spain

Yesterday spent the day in the Cardona area, visiting the main local attraction, which is the mountain of salt that first made this area prosperous. The mine in the folded mountain formation is no longer active, but you can tour part of the old works, which allows you to see some of the tunnels miners used, but, more interestingly, it allows you to see the salt formations in detail. Mining in this area goes back to neolithic times and the Romans extracted salt here as well. It wasn't until fairly recently that vertical shafts were dug into the deposit to mine it.

There are only three places in the world where salt deposits have been folded vertically into a mountain. One is in Colombia, one is in Romania, and one is here. The deposits originated in an arm of the Atlantic Ocean that once covered most of Catalonia. They are about 40 million years old. Stained with iron oxide, they are mostly shades of brown and orange, but fresh crystals of white sodium chloride (common table salt) have formed on the surface of the ancient deposits in many areas because of water seepage. There are impressive salt stalactites in places.

At least three kinds of salt are present, sodium chloride (halite), potassium-magnesium chloride, (carnalite), and another, that I've forgotten the name of that is mostly potassium chloride. The carnalite crystals were especially pretty, looking like topaz and in some places like the stone carnelian (the names share a root, of course; carne, or "meat," which is appropriate as some of the ubiquitous Spanish hams look rather like carnelian, too).

Commercial mining in the 20th century seems to have focused on extracting potassium salts. The unwanted sodium chloride was dumped next to the natural formation. In the first photo here, the ancient folded salt dome is the area of exposed cliffs. The flat area with machinery on it and the area just behind that is the dumped mine waste that is itself now being "strip mined" for sodium chloride for industrial applications. Worth a visit.