Mill sandstone

Mill sandstone is a local formation of a type of sandstone . In the vicinity of Waldshut in Baden-Wuerttemberg as a millstone bank, it was largely mined in underground quarries and mainly used for the production of millstones .

geology

The layers of Waldshut mill sandstone lie directly on an iron-bearing gneiss layer of the basement . This basement is overlaid by an overburden of red sandstone . The layers of the overburden are composed of the overhead red claystone the Röt formation , underlying clay , red and violet sandstone with Karneol - a banded variety of chalcedony together and bottom-coarse Mühlsandstein -.

Occurrence

Sandstone quarries were operated in the Hotzenwald in the deposits of the Upper Buntsandstein . The best qualities for making millstones were found in the Waldshut millstone pit and in the Kilian millstone pit.

Rock description

Mill sandstone consists of silicified quartz and is very solid. The silicon dioxide content is between 98.68 and 99.56%. The color is white to a faint purple. The millstone-capable layer is 7 to 8 feet (2.10 to 2.40 m) thick , making 2 to 4 millstones each.

use

Only the best quality could be used for the production of millstones and high-speed grindstones. Stones with cracks or composite stones were girded with wrought iron bands, they were much cheaper.

The standard size of the millstones was about 1.20 m in diameter, in the rest of the Black Forest 1.04 m. But special stone sizes were also made, a single millstone had a diameter of 3.813 m. The millstone thicknesses were manufactured according to customer requirements.

In the other neighboring smaller pits and quarries, less millstone-compatible quantities and qualities were found. The red sandstone quarries near Unteralpfen were opened in order to extract building stones and stone for the new construction of the St. Blasien monastery . Stones extracted there were used, among other things, to build bridges for the Hochrheinbahn and to build the church in Unteralpfen. Stratigraphically comparable sandstones can also be found in Roggenbach Castle , the Steinegg ruins and the Wieladingen castle ruins .

See also

• List of sandstone types

literature

• Rudolf Metz : Geological regional studies of the Hotzenwald. With excursions, especially in its old mining areas. Schauenburg, Lahr 1980, ISBN 3-7946-0174-2 .
• Julius Ludwig Wilser: Stratigraphic and tectonic structure of the southwestern Black Forest . In: Volume 11, 37 Advances in Geology and Palaeontology . Borntraeger brothers, 1932
• Kurt Obenauer: To the knowledge of the triad between Waldshut and the Albtal . In: Reports of the Natural Research Society Freiburg , 1928
• Adolf Strigel: The southern German red sandstone basin . Communications and work at the Geological - Paleontological Institute of Heidelberg University. New series (since 1915), no.168, Hörning Heidelberg, 1929
• Norbert Gottschlich: Contributions to the geology of the area between Schlücht and Alb , dissertation, Freiburg i. Brsg., 1950
• Dieter Ortlam: The edge facies of the Germanic red sandstone in the southern Black Forest . In: Geological Yearbook 89; 1970
• Manfred Lutz: Stratigraphic and tectonic investigations on the southwestern edge of the Black Forest between Wiesenthal and Hochrhein , Oberrheinische Geologische Abhandlungen 13, 1964
• Julius Schill: Geological description of the surroundings of Waldshut , In: Contributions to the statistics of the internal administration of the Grand Duchy of Baden , Issue 23, 1867

Individual evidence

1. ^ Rudolf Metz, Geological regional studies of the Hotzenwald. With excursions, especially in its old mining areas. P. 93 and p. 558 ff.
2. ↑ Some information about the Hotzenwald ( memento of the original from June 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. on salpeter.net. Retrieved June 2, 2014. 
3. ^ Rudolf Metz, Geological regional studies of the Hotzenwald. With excursions, especially in its old mining areas , p. 558 ff.