The Mühlsteinbrüche ("Millstone Quarries", ) south of

Jonsdorf The community of Jonsdorf is located in the south of the Kreis Görlitz in the southeast of the German federal state of Saxony. It is embedded into a valley of the Zittau Mountains, part of the Lusatian Mountains. History In 1539 Jonsdorf was fir ...

in the

Zittau Mountains The Zittau Mountains (, ; ), formerly also called the Lusatian Ridge (''Lausitzer Kamm''; ''Łužiski česak''), refer to the German part of the Lusatian Mountains that straddle the Saxony, Saxon-Bohemian border in the extreme southeast of the ...

Saxony Saxony, officially the Free State of Saxony, is a landlocked state of Germany, bordering the states of Brandenburg, Saxony-Anhalt, Thuringia, and Bavaria, as well as the countries of Poland and the Czech Republic. Its capital is Dresden, and ...

are a region of bizarre rock formations, which have been formed by the quarrying of

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

for

millstone Millstones or mill stones are stones used in gristmills, used for triturating, crushing or, more specifically, grinding wheat or other grains. They are sometimes referred to as grindstones or grinding stones. Millstones come in pairs: a s ...

s and also by

weathering Weathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs '' in situ'' (on-site, with little or no move ...

processes. They are a popular

hiking A hike is a long, vigorous walk, usually on trails or footpaths in the countryside. Walking for pleasure developed in Europe during the eighteenth century. Long hikes as part of a religious pilgrimage have existed for a much longer time. "Hi ...

and climbing area. An

educational trail An educational trail (or sometimes educational path), nature trail or nature walk is a specially developed hiking trail or footpath that runs through the countryside, along which there are marked stations or stops next to points of natural, techn ...

runs through the region which has an area of about 35 hectares.

Location and surrounding area

The Mühlsteinbrüche are located south of

at a height of 480 to 560 metres. To the southwest they are adjoined by the Jonsdorfer Felsenstadt. About 600 metres to the south is the border with the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

Geology

The sandstone in the Mühlsteinbrüche region was formed in the geological age of the Middle Turonian and, based on its formation, belongs to the Bohemian Cretaceous Basin. It is characterised by several special features. For example, the sandstone, which was formed by sedimentation, has been breached multiple times by

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

ic and phonolitic

intrusions In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of Intrusive rock, intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety o ...

as a result of contact with occurrences of Tertiary volcanism in

North Bohemia North Bohemia (, ) is a region in the north of the Czech Republic. Location North Bohemia roughly covers the present-day NUTS regional unit of ''CZ04 Severozápad'' and the western part of ''CZ05 Severovýchod''. From an administrative perspec ...

. Often, in these cases, the rock has been exposed to thermal changes (contact with

magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as ''lava'') is found beneath the surface of the Earth, and evidence of magmatism has also ...

and hydrothermal fluids), which has led to

vitrification Vitrification (, via French ') is the full or partial transformation of a substance into a glass, that is to say, a non- crystalline or amorphous solid. Glasses differ from liquids structurally and glasses possess a higher degree of connectivity ...

of the rock (a melting of mineral grains at their grain boundaries). The sandstone retains its porosity, is hardened by the strength of its grain structure and thus its abrasion resistance is increased. Muehlst

The area of Mühlsteinbrüche has as additional geological feature: its pronounced columnar sandstone. Its best known rock formation is the ''Große und Kleine Orgel'' ("Great and Little Organ"), whose appearance is easily confused with that of columnar

. The columns, which are completely atypical for sandstone, have a diameter of up to 15 centimetres and are bundled vertically on a solid, non-columnar sandstone block. They have been formed by thermal processes as a result of contact with

. In 1852

Alexander von Humboldt Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 1769 – 6 May 1859) was a German polymath, geographer, natural history, naturalist, List of explorers, explorer, and proponent of Romanticism, Romantic philosophy and Romanticism ...

sent an artist and two geologists here to study this phenomenon.

History

The use of sandstone in the Zittau Mountains for the production of

s was already under way from the 16th century. The Jonsdorf Mühlsteinbrüche were one of more than 40 quarrying sites in the surrounding region. In 1560, quarrying began in Jonsdorf itself. Over 350 years, sandstone was quarried here and made into millstones with a diameter of up to 2.70 metres. To do this, the millstones were initially hewn out of one piece of rock. From about 1850, millstones were assembled from several pieces as there were no longer any sufficiently large and homogeneous sandstone blocks being quarried. Production was maintained until 1918. The main markets were in

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

and

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

Moscow Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...

and

Saint Petersburg Saint Petersburg, formerly known as Petrograd and later Leningrad, is the List of cities and towns in Russia by population, second-largest city in Russia after Moscow. It is situated on the Neva, River Neva, at the head of the Gulf of Finland ...

had their own offices for the millstone trade. In the 1950s, a

nature trail An educational trail (or sometimes educational path), nature trail or nature walk is a specially developed hiking trail or footpath that runs through the countryside, along which there are marked stations or stops next to points of natural scienc ...

was laid out by friends of nature and local history. From 1990, a restoration of the quarries was begun in order to make them accessible. In 2002, a demonstration workshop was built in the ''Schwarzer Loch'' ("Black Hole"). Today the Mühlsteinbrüche are a major attraction in the Zittau Mountains.

Sights

*Rock formations: **''Drei Tische'', kidney-shaped sandstone rock formation, formed from iron oxide precipitation **''Mausefalle'' ("Mousetrap"), a rock formation created by a rock collapse in 1908 **''Nashorn'' ("Rhino") and ''Bernhardiner'' **''Große und Kleine Orgel'' ("Great and Little Organs") **''Löwe'' ("Lion") **Humboldtfelsen ("Humboldt Rock"), a 7-metre-high basalt shaft in the ''Schwarzer Bruch'' ("Black Quarry") **Schnapslager **''Rutsche'' ("Slide") *Old quarries **''Bärloch'' ("Bear Cave") **''Weißer Felsen'' ("White Rock") **''Schwarzes Loch'' ("Black Hole") with its demonstration workshop and tunnel **''Kellerbergbruch'' *Old Smithy: ** ''Steinbruchschmiede''

Literature

* Andreas Gerth: ''Geologische Exkursionen in der Oberlausitz und im Elbsandsteingebirge''. Oberlausitzer Verlag Spitzkunnersdorf, 2006; * ''Meyers Naturführer Oberlausitz''. Meyers Lexikonverlag Mannheim/Leipzig/Vienna/Zurich; *

External links

Mühlsteinbrüche webpage by the Jonsdorf Mountain Club
{{DEFAULTSORT:Muhlsteinbruche Grinding mills Rock formations of Saxony Zittau Mountains Quarries in Germany Görlitz (district) Building stone