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Mining activities on the Bartholomaeberg

by Theresa König last modified 2008-02-19 15:30

Mining activities on the Bartholomaeberg



According to recent archaeological investigations, permanent settlements have existed since about 3000 BC. Starting with the onset of the Copper Age at around 2000 BC, the search for ore began. At that time, the most interesting minerals / ores were limonite which is oxidized iron ore, green malachite and blue azurite both of which result from the oxidization of copper. These multi-coloured minerals attracted the interest of the early miners because they soon realized that these minerals indicate larger and richer depots of ore. Moreover, the oxides of iron and copper could be melted at low temperatures.

The ores at Bartholomaeberg – Kristberg are restricted to the transition zone of the Silvretta Crystalline to the overlying sediments of the Northern Calcareous Alps. The ores originate from old volcanoes which, 285 million years ago, spewed  ignimbrites which are clouds of lava, that were rich in copper, barite, silver, gold, uranium, lead and iron. Over hundreds of thousands of years, parts of the ores were eroded, transported and finally deposited in placers or alluvial deposits. These placers –which were very rich in ore – were covered by several hundreds of metres of sediments from the Northern Calcareous Alps. During the uplift of the Alps, these ores were dissolved in water with temperatures of about 200° to 300° C and extreme pressure. The hot solutions circulated along clefts and joints and became enriched. Because the contact zone of sediments with crystalline rocks became inverted through Alpine tectonics, the former basement is now resting on the younger sediments and forms their roof. During their path upward along the clefts and joints, the hot solutions with their dissolved ores cooled off, resulting in the crystallisation of ore minerals in ore veins. These veins were the reason for the mining activities in medieval times between 1000 and 1600 AD. During the construction of the road from Schruns to Bartholomaeberg a very thick copper vein was hit upon just below the church.

Based on chemical analyses of the soil and water from springs at Bartholomaeberg and Silbertal, as much ore as was mined in medieval times can be expected in the lower parts of the slopes. However, environmental protection laws and safety- at- work laws make mining in the beautiful landscape of Bartholomaeberg impossible.  Moreover, from an economic point of view, mining would not be profitable. Human moles mining all over the slope - like in the old days – is simply unimaginable.


Audiofile

P07-1 Mining Activities on the Bartholomaeberg.mp3
 


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