Field stone (building material)
In architecture and construction, the term field stone refers to a building material made of natural stone whose individual pieces rarely have edges and are not trimmed with tools. They are used for the purpose of field stone construction; it is occasionally used as a synonym for reading stone .
Field stones are reading stones and subordinate also in open-cast mining ("stone pits") extracted debris from ice age loose rock of northeast Germany, the block packings of the Baltic ridge . Field stones as reading stones are stones and blocks lying on meadows , pastures and fields, which are read and collected at the field margins or driven off. In northern Central and Eastern Europe, they are usually well rounded due to glacial transport and, as a rule, cannot be stratified, but were collected in rock heaps and walls. In the regions that are covered with loose rock from the Ice Age, the field stones are the only solid rocks. They were often used as building material in these regions. Stones from large stone graves were also used and the grave facilities were destroyed.
Origin of the field stones
The field stones are debris that was transported from Scandinavia by the Ice Age glaciers and was deposited when the glaciers melted. Due to the glacial transport, they are usually well rounded. The proportion of metamorphic and igneous rocks is in accordance with the upcoming Scandinavian origin area usually very high; Sedimentary rocks are therefore very subordinate. Through weathering, erosion and soil mechanical processes, but also through tillage , they were and are brought to the surface of the earth.
However, they are not evenly distributed in the ice age unconsolidated rock. Field stones are often found on ground or terminal moraines, for example . Before the colonization of these areas of northeast Germany (Brandenburg, Mecklenburg-Western Pomerania, Saxony-Anhalt) in the 12th and 13th centuries, many areas were literally littered with fieldstones that had to be cleared during reclamation .
Field stones as building material
Many pre-Romanesque and early Romanesque church buildings - especially in rural areas (e.g. St-Ferréol-de-la-Pave, etc.) - are built from poorly hewn field or rubble stones. This tradition lasted longer with secular buildings such as castles , tithe barns , residential houses, etc.
In Brandenburg (including Neumark ), Saxony-Anhalt , Mecklenburg , Pomerania , Schleswig-Holstein and Lower Saxony , field stones were used to build field stone churches, particularly in the 12th to 15th centuries . The front side was initially cut into blocks. In later buildings, mostly only split field stones were used. Large quantities of field stones (walls, houses, streets) were also required to build the medieval cities.
In the 19th century, field stones in Brandenburg and northern Saxony-Anhalt were also used to build houses (e.g. agricultural buildings) or fencing walls. However, they were not broken into blocks, but only split once or twice and the outer surfaces of the walls were then “entangled”, i.e. H. the gaps between the stones are filled with rock fragments.
In the 19th and at the beginning of the 20th century, field stones were used on a large scale for the construction of the highways , where they were processed into curbstones and paving stones. In the Uckermark , field stones were even mined from the moraines in "stone pits" or "foundling graves". In addition, gravel dredgers and gravel works in northern Germany also use these deposits. During this time there were numerous mining operations in Germany in the provinces of East Prussia , West Prussia , Brandenburg , Pomerania and Posen . There was significant dismantling, for example, in the former Angerburg district and by the former Uckermärkische Steinwerke with their facilities in Fürstenwerder near Prenzlau and in Feldberg .
Conservation and natural monument
Stone heaps are considered rare or valuable habitats because of the heat storage and the cavities and are therefore protected by nature conservation law in Brandenburg, Schleswig-Holstein and Lower Saxony , as they are an important habitat for reptiles , insects and plants . Often, a field stone heap also develops into a small wood or bush .
- Hillert Ibbeken : The medieval field and quarry stone churches in Fläming. Berlin-Verlag Spitz, Berlin 1999, ISBN 3-8305-0039-4 .
- Carl Gäbert, Alexander Steuer, Karl Weiss (all ed.): Handbook of the stone industry. Volume 1: The usable rock deposits in Germany. Weathering and conservation of rocks. Union Deutsche Verlags-Gesellschaft, Berlin 1915.
- Günter Mehling (Ed.): Natural stone dictionary . Callwey-Verlag, Munich 1993 (4th edition), p. 153
- Hans Koepf , Günther Binding : Picture Dictionary of Architecture (= Kröner's pocket edition. Vol. 194). 4th, revised edition. Kröner, Stuttgart 2005, ISBN 3-520-19404-X , pp. 170–171, entries field stone and field stone construction .
- Märkische Eiszeitstraße: field stone buildings. ( Memento of the original from April 10, 2006 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. Society for the research and promotion of the Märkische Eiszeitstraße (MES) Eberswalde
- Gäbert, Steuer, Weiss: Handbook of the stone industry. Volume 1. 1915, pp. 16-20.