Stone mill

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A traditional stone mill near Lienz.
The core of the ball mill near Marktschellenberg
Ball mill in Fürstenbrunn

Stone mills , also known as ball mills or Märbelmühlen , were used in past centuries for the cylindrical grinding of stones.

Working principle

From a suitable rock that is as homogeneous as possible, such as B. marble , granite starting, pieces are roughly pre-cut in spherical shape . Some of these raw balls are placed in a circular running groove in a horizontal disc, possibly made of sandstone. On top there is a second disc, which can also be made of hardwood and has an opposite groove. If the upper disk is driven, as is often the case, by water power via an impeller slightly above it in a water jet, then the grinder can simply be rinsed continuously with water. When rolling relatively slowly in the grooves and when hitting one another, the stones selectively abrade the protruding bumps. Irregularities and the curvature of the groove also continuously change the rolling axis of the stones, which means that they are slowly circulated across the rolling direction, so that the grinding process leads to perfectly perfect balls of roughly the same size within a few days. The stone balls are then removed from the stone mill and then, if necessary, receive their usable smooth surface through a final polish .

Märbelpicker

The Märbelpicker tapped the stone into dice with a pointed hammer , so that these could be ground into marbles in mills. He dug the limestone required for this from shafts up to 20 meters deep and carefully covered it in wooden huts. The Märbelpicker tapped up to 10,000 small cubes a day.

use

There were / are various uses for the stone balls:

  • Stone balls were used for a long time as ammunition for artillery and also for the medieval catapults . They are said to have been used as non-explosive ammunition for cannons and howitzers until the first half of the 19th century , whereby small stones (marbles) were originally used in naval warfare to shoot enemy rigging. Due to the increasing availability of reliable and safely manageable explosive ammunition, stone balls lost their importance, explosive ammunition was cheaper and more suitable.
  • The stone balls were also used as an aid for seafaring. If the ships were still without cargo in one direction, their keels were held deep enough under the water by the heavy marbles.
  • Stone spheres are also used commercially, for example in rotary drums for deburring and for surface treatment.
  • Stone balls or fairy tales are popular children's toys . The mill trade for the production of marbles made of limestone was widespread in the Meininger Oberland , among others . In 1900 there were 87 Märbelmühlen in operation.
  • Often stone balls are also popular because of their appearance, especially if semi-precious stones or precious stones were used as the starting material . Larger stone balls are used as decorative elements in architecture .

Today's design

Nowadays the traditional stone mills are no longer used, but highly developed industrial mills .

Foam mills

The last traditional ball mill in Germany is located in the Bavarian market town of Marktschellenberg . The facility, founded in 1683, is one of the 40 Untersberg marble ball mills on the Almbach and is one of the oldest commercial operations in Bavaria .

A newly built ball mill is located on Seebach in Neidlingen am Albtrauf in Baden-Württemberg , where local Jura marble is ground. It has been operated as a sideline since 2005. The Neidlinger Kugelmühle has been a Geopoint of the UNESCO Geopark Swabian Alb since July 2016 .

Further ball mills can be found in the Untersberg Museum in Fürstenbrunn , Austria, and on the forecourt of the Natural History and Mammoth Museum in Siegsdorf in the Upper Bavarian district of Traunstein .


  • Ball mill Neidlingen

  • Opened grinder

  • Lower part made of sandstone

  • Preprocessing stages

  • End products

swell

  1. ↑ Süddeutsche Zeitung: Forgotten Professions: These jobs no longer exist. Retrieved May 9, 2020 .
  2. ↑ Günther Hoppe, Jürgen John: Sites and monuments of history in the districts of Erfurt, Gera, Suhl (= historical guide. ). Urania-Verlag, Leipzig et al. 1978, p. 249 f.
  3. ^ Robert Darga: Südostbayerisches Naturkunde- und Mammut-Museum Siegsdorf, Weltkunst Verlag Munich 1998, page 13

Web links

Commons : Steinmühlen  - Collection of images, videos and audio files

Replica of a historical ball mill in Seehamm / Austria, which is still in operation today: http://www.teufelsgraben.at/Kugelmuehle/Dia/index.html / http://www.teufelsgraben.at/pages/kugelmuehle.html#