Minerals are natural crystals
Minerals are natural crystals – solid matter whose atoms are organised in accordance with strict geomatrical principles. This internal order is also mirrored in the surface of the crystals, which is often incredibly smooth. Besides shape, colour is a striking feature of many crystals. Some of them have a characteristic hue, while others can be found in a wide variety of different colours.
Most of our planet consists of minerals. However, many of the 4,000 known types of minerals tend to be inconspicuous parts of rocks.
Swiss Alps
Where minerals have had an opportunity to grow undisturbed in particularly favourable conditions over long periods, we can now find spectacular crystals, and the Swiss Alps have long been famed for their treasure troves of beautiful crystals. The commonest mineral in Switzerland is quartz, but many other equally attractive types are there for the finding. These fully formed Alpine minerals have grown in what are called fissures (Zerklüfte), cavities that were torn open as the result of pressures in the rock during the formation of the Alps. The minerals were formed at depths of between 10 and 15 km, at temperatures of 300 to 4500 grades Celsius in the presence of aqueous solutions.
Alpine crystals
With their age of between 10 and 20 million years, the Alpine crystals found in fissures are very young formations on the geological scale. However, tracking down attractive rare minerals is not easy. Hunting for crystals is a demanding activity that also requires a lot of specialised knowledge, patience, experience of the various types of terrain and last, but not least, a bit of good luck.
Issue: Switzerland, 17 September 2002
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Towns
Facts and figures about Swiss cities.
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