16 | 10 | 2013

Alpine  |  Europe  |  Calcite

The mining district of St. Gertraudi near Schwaz in Tyrol

The mines around St. Gertraudi in Tyrol, Austria, are part of the big medieval mining district of Schwaz in the Inn valley. The silver mining of this region began in the 15th century. Especially the historic tunnels and shafts are fascinating mining samples. Handmade tunnels, where it’s impossible to walk upright are followed by huge caverns which can hardly enlightened by the headlights. There are many points where you can find so called Kienspäne (long wooden sticks, which were used as torches), relicts of the hard medieval work underground. For collectors, Schwaz stands for fantastic Azurit crystals and wonderful specimen of Dolomite and Baryt.

The ore bodies are located in fault zones of the Dolomite. They contain smaller and bigger cavities up to more than one meter. These holes are mostly covered with dolomite crystals between 2-10mm. They are often arranged in hedgehog like pieces. In some areas, these specimens are carrying Calcite crystals up to 2 cm. most of the Calcite are shaped as scalenoedric crystals. Although Baryt appears quite often as non-crystalized masses, good specimens, so called Spathauben, are very rare.

The Inn valley in Tyrol, Austia.

The Inn valley in Tyrol, Austia.

The most famous mineral of the mining district Schwaz is definitely Azurite. This mineral occurs mostly in small crystals, arranged as a blue carpet on top of the white matrix. Sometimes they are arranged as 1-2 mm big balls. Especially small cavities are in general completely covered with these crystals. In some cavities there were found specimen of Azurite in combination with Malachite and Chrysolkoll, a colourful combination which is definitely a wonderful completion to an alpine collection.

A very interesting arrangement are specimens, where partially with Azurite covered Calcite or Baryte crystals sitting on top of the dolomite matrix. These specimens are very rare and quite popular. Malachite occurs mainly together with Chrysolkoll as crust like covers on top of the dolomite. Only in some rare cases, balls up to more than one centimetre where found.

There are several mining Museums in the surrounding, which give a great insight into the mining wold and the crystals of Schwaz.

Fotos / Credits
Matthias Benz / Germany

Autor / Author
Matthias Benz / Germany