Halite speleothems

In the gallery of the Cardona potash mine that is named La Minilla and that can be visited through the service of the Salt Mountain Cultural Park, there are a lot of speleothems of the mineral halite, as in the natural caves of Forat Micó and Meanders of Salt, all of them inside the Mountain of Salt.

Speleothem refers to any shape of the secondary deposition of minerals into cavities. The best known speleothems are stalactites hanging from the ceiling, but there are other forms such as macaroni, stalagmites growing from the ground, columns, curtains, flowers… Speleothems are made of soluble minerals, mostly of calcium carbonate that crystallizes in calcite or aragonite; rarely they can be made of calcium sulphate that crystalizes in gypsum or in anhydrite or small fragile macaroni of hydrated magnesium sulphate and, even more exceptionally, there are speleothems of common salt crystallized in the mineral halite.

La Minilla is a horizontal gallery for ventilation purpose from the deep mine Nieves in Cardona mine. It is dug into the salt rock, at the foot of the Salt Mountain. Water drips from its ceiling, even more in rainy days. As a result, this gallery not only shows the sinuous veins of the orange-toned salt rock, but also halite deposits in stalactites and coatings of delicate, fragile, so beautiful shapes. Language has no words to describe this underground world. Therefore, let’s leave it under the generic name of speleothems and see a few pictures.

[photos Montserrat Porta and Jordi Badia]