Flossenbürger granite
The Flossenbürg granite is extracted in the vicinity of the town of Flossenbürg in the Upper Palatinate Forest . It is a yellow-gray, medium-grain granite that has been proven to have been quarried in several quarries since 1769. It is a two mica granite from the upper carbon . There are two types of rock, the Flossenbürg blue and the Flossenbürg yellow-gray.
Mineral inventory
The granite contains 36 percent quartz , 31 percent alkali feldspar , 19 percent plagioclase , 6 percent biotite , 5 percent muscovite and chlorite and 3 percent accessories such as apatite , tourmaline and opaque ore.
By Limoniteinlagerung this Granite is slightly yellowish and quartz gives him the blue-gray color. The mica deposits are biotite and muscovite. Biotite deposits create the granular structure and muscovite appears in the form of tiny, silvery, shiny scales. The grain sizes are around 1.5 to 2.0 millimeters.
geology
The Flossenbürger granite is part of the North Upper Palatinate Pluton , which extends over an area of 50 × 20 kilometers. The pluton was formed around 300 to 350 million years ago, the Flossenbürger granite around 310 million years ago. When the continents collided, magma bubbles invaded the earth's crust. The magma froze at a depth of several kilometers. When the area was raised, the granite came to the surface. It formed part of the Variscan orogeny , a mountain formation.
The granites formed in the earth's interior under high pressure conditions; When it rose to the surface of the earth, the deposit was relieved and this resulted in the formation of fissures that run parallel to the surface of the earth in the Flossenbürger granite. These horizontal fissures have a small distance near the surface, which increases in depth.
Flossenbürger Granit is characterized by an increased natural radioactivity , during which, among other things, the gas radon is released.
A geological specialty is the granite shell dome on which Flossenbürg Castle is located. The shell dome is part of the Bavarian-Bohemian Geopark . The Schlossberg is a nature reserve in which no granite has been quarried since the 1960s.
Occurrence and use
The Flossenbürger granite is one of three large deposits, the Leuchtenberger granite, Flossenbürger granite and Bärnau / Rozadov granite. The occurrence allows the extraction of large-volume rough blocks, since the rock banks are hardly fissured vertically.
Flossenbürger granite is very weather-resistant, wear-resistant, polishable and stable against chemical aggressions. In manual stone processing, it is considered "furry", which means that it requires more effort than other granites. This granite can be used as flooring, paving stones, ashlar, stair and facade covering, window and door frames, for bridge structures, tombstones, curbs and boundary stones as well as sculptures.
History of stone extraction
From 1769
Granite has been mined in Flossenbürg since 1769. In 1802 the government councilor Johann Daniel Höck reported that " the Flossenbürger granite can be worked a little finer because of its fine core " and that the Flossenbürger stones are probably known to every Upper Palatinate. The stones produced at the time were objects of construction and everyday use such as bricks, stairs, door and window frames, garden posts, water troughs, cabbage barrels, etc. In 1814 the municipality of Flossenbürg bought the Schlossberg and leased it for a "fraction". The largest quarry on Schlossberg was owned by Johann Georg Horn in 1865.
When the granite industry developed in Germany, processing plants were established in the immediate vicinity of the granite deposits from 1850 onwards. In Flossenbürg this development was favored by the construction of the railway in 1886 to Floß , as this lowered the transport costs. But it was not until 1913 that Flossenbürg was connected to the railway network to Floß. The railway system that was developing at that time gave the granite quarries a new impetus, as bridges and track systems for the railway as well as water dams were built from durable stone material. At that time there were 25 quarries with 300 workers in Flossenbürg.
The economic crisis of 1929 hit the medium-sized granite industry and quarrying companies particularly hard, and from 1929 to 1931 all of the factories had to close. There were hardly any employment alternatives in Flossenbürg, since tourism as an alternative was not developed as strongly as in other areas of the Upper Palatinate. Due to the planning of the National Socialists there was an increased demand for natural stone and from 1934 full employment was again in the granite industry, whereby mainly granite material was produced for the building project of the Nazi party rally grounds in Nuremberg.
From 1938
On April 29, 1938, the Deutsche Erd- und Steinwerke (DESt) was founded in Berlin as a company of the SS , which set up the Flossenbürg concentration camp . Until 1945, concentration camp prisoners had to work and live there under inhumane conditions.
At the beginning of the construction of the camp, the prisoners had to open up the quarry area with simple tools such as picks and shovels and help the stonecutters, some of whom came from Flossenbürg, and do handyman services when setting up the stones.
In 1940 902 prisoners worked for the DESt in the Flossenbürg concentration camp for stone production. In 1939 and 1940 they mainly produced stone for bridge and road construction projects. Heinrich Himmler visited the Flossenbürg concentration camp in April 1940 and ordered 100,000 m³ of stone material to be produced by 1943 for the construction of the Reich capital Berlin ( World Capital Germania project ), of which Flossenbürg was to deliver 12,000 m³ annually. Since the stone production did not meet the required quality despite the increased output, around 500 prisoners were trained as stonemasons in the winter of 1941 and 1942. From October 1942, an additional 500 Red Army soldiers had to work in the quarries.
After 1945
Granite is mined in Flossenbürg to this day, and the concentration camp quarry continued to operate after the end of the Second World War . In 2006 the concentration camp site with the quarry was declared a memorial.
On the Schlossberg, which was dismantled until 1958, further dismantling is no longer possible for nature conservation reasons.
In 2009 there were still four granite factories producing in Flossenbürg.
Stone carving museum and "Path of the Granite"
A 1.8 kilometer long granite path leads around the Schlossberg with a stone cutter's hut , lorries for stone transport and processing samples of this granite. There is a stone carving museum in Flossenbürg.
See also
Web links
- Stone carving and castle museum
- The granite dome of Flossenbürg
- Stone workers in the quarry on the Burgberg (1896) at www.gedenkstaette-flossenbuerg.de
- Illustration by Flossenbürg Blau: Building materials collection of the Faculty of Architecture at the Technical University of Munich
- natursteinonline.de : Image of Flossenbürg Yellow
Individual evidence
- ^ Wolf-Dieter Grimm: Pictorial atlas of important memorial stones of the Federal Republic of Germany. Edited by the Bavarian State Office for the Preservation of Monuments, Rock No. 004, Lipp-Verlag, Munich 1990, ISBN 3-87490-535-7 .
- ↑ Bavarian State Office for Geology: Schlossberg Flossenbürg , accessed on February 24, 2019.
- ↑ Stuttgarter Zeitung: City has radioactivity measured on Königstrasse , accessed on October 11, 2012.
- ↑ Geopark Bavaria , accessed on July 24, 2009.
- ↑ Paul Praxl : The history of the granite trade in Eastern Bavaria. In: Winfried Helm (Ed.): Granit. Kellberg 2007, ISBN 978-3-00-023087-5 , p. 97.
- ↑ a b Praxl: History of the Granite Industry, p. 98.
- ↑ Wolfgang Benz , Barbara Distel (ed.): The place of terror . History of the National Socialist Concentration Camps. Volume 4: Flossenbürg, Mauthausen, Ravensbrück. CH Beck, Munich 2006, ISBN 3-406-52964-X , p. 18 ( Google fragment available online ).
- ↑ Benz: Place of Terror, p. 30.
- ^ Benz: Place of Terror, p. 32.
Coordinates: 49 ° 44 ′ 1.8 ″ N , 12 ° 20 ′ 40.6 ″ E