Bratschen are weathering products that occur as a result of frost and aeolian corrasion almost exclusively on the calc-schists of the Upper Slate Mantle (Obere Schieferhülle) in the High Tauern mountains of Austria. The term is German but is used untranslated in English sources. It may be the equivalent of the New Zealand climbers' term 'weet-bix' for a rock that disintegrates easily and so is difficult to climb on.
The calc-schist, that appears blue-gray when freshly broken, weathers to a yellow to brown colour and flakes off on the surface to form bratschen.
These form steep (up to 40°), rocky, almost unvegetated mountainsides with an odd and rough-textured surface, caused by wind erosion. Bratschen are found on the mountains such as the Fuscherkarkopf, the Großer Bärenkopf, the Kitzsteinhorn, the Schwerteck or on the – eponymous – Bratschenköpfen.
- For example here: Kendlspitze at www.summitpost.org. Retrieved 12 Dec 2016.
- H. P. Cornelius, E. Clar (1935), Geologische Bundesanstalt — Wien III, ed., [pdf, geologie.ac.at "Erläuterungen zur geologischen Karte des Großglocknergebietes"] (in German), Geologische Karte der Republik Österreich: pp. 10, pdf, geologie.ac.at. Retrieved 2010-05-05