Werler green sandstone
Werler Grünsandstein is a limestone that is extracted and used in the Soester Börde , among other places . It comes from the Turonium , a level of the Upper Cretaceous . It occurs in Werl in North Rhine-Westphalia and is no longer dismantled today (2008).
Occurrence and naming
The green sandstone deposits in the south of the Westphalian Chalk Bay between Haarstrang and Lippe have different mineral compositions and technical properties. From a technical point of view, only those rocks are important that were previously mined near Soest , Werl , Anröchte and Rüthen . The Werler green sand quarry has brown, weathered stone material in the upper layers and at the crevices . The rock banks below are colored green. In Werl, brown and green ashlar were built into facades. Around Werl-Büderich and on Windmühlenberg near Werl there used to be 8 stone quarries.
The local miners use the name green sandstone to refer to all sands that occur there, insofar as they are solidified and colored green. This rock designation was then preceded by the respective location.
mineralogy
It is a lime-bound sandstone , which to a small extent can also be bound in pebbles. It consists of 49 percent extra clasts (27 percent of which are carbonate clasts and 22 percent are glauconite ). Biogenic clasts amount to 32 percent and the quartz share has a share of 18 percent; it also contains fragments of rock, mica and feldspar with a share of 1 percent. Glauconite, a weathering mineral , colors this natural stone green. The most common grain size is 0.08 millimeters and the stored fossil debris is heavily ground. The rock was sedimented in what was then the warm Upper Chalk Sea, where fossils were also deposited.
The Werler Grünstein is a soft stone that is particularly badly attacked by the weather and industrial emissions. This is related to its proportion of lime and calcareous binder. The calcareous binding agent and glauconite decompose in the weathering processes. The Werler stone shows little resistance to weathering , shows partial dissolution, small-scale peeling and gypsum efflorescence.
use
Buildings that were built from Werler green sandstone are the parish church of St. Walburga (Werl) , the pilgrimage basilica of the Visitation of the Virgin Mary (Werl) , castle ruins, Wortmanns watermill, manor chapel in the Koenigen manor in Werl. This green sandstone was mainly used for solid buildings, bricks, window and door frames and stairs.
See also
literature
- W. Dienemann and O. Burre: The usable rocks of Germany and their deposits with the exception of coal, ores and salts, Enke-Verlag, Stuttgart 1929, p. 296ff
- Wolf-Dieter Grimm: picture atlas of important monument rocks of the Federal Republic of Germany. Published by the Bavarian State Office for Monument Preservation, Lipp-Verlag, Munich 1990, ISBN 3-87490-535-7 .
Individual proof
- ↑ Grimm, picture atlas of important monument rocks, rock no.144 (see literature)