Normandy: Middle Jurassic Building Stones (Lead Author WGT)
Middle Jurassic limestones (contemporaneous with the Bath Stone of England) have long been quarried above and below ground in the area around Caen in the department of Calvados in Normandy, NW France. From the 11th century, southern England (Dorset, Hants & West Sussex) was the main importer of stone from this area. Building Stone was also imported from the Pas de Calais department (Marquise area) opposite the Kent coast.
The best-known finest quality stone used for ornamental work in English Cathedrals and Churches is the Pierre de Caen which is the upper part of the Calcaire de Caen (Caen Limestone Formation). The overlying Calcaire de Cruelly (Cruelly Limestone Fm), the Calcaire de Blainville (Blainville Lst Fm), the Calcaire de Renville (Renville Lst Fm) and the youngest Calcaire de Langrune (Langrune Lst Fm) are all cross-bedded shelly bioclastic and oolitic limestones (details above).
Additional information from Prof. Dugué (Univ Caen) March 2019
Calcaire de Ranville: Tomb slabs; decimetre bedded, X-bedding. Well-cemented, rich in echinoderm debris
Calcaire de Blainville: Oolitic, often internal use , e.g. stair steps, perhaps inner pillars
Calcaire de Cruelly: Fine bioclastic, siliceous horizontal to oblique bedding, readily seen in monuments
Pierre de Caen: More homogeneous, siliceous lenses at the top not used. Some levels rich in small
pelletoids; microfossils very rare.
Calcaire de Ranville: Tomb slabs; decimetre bedded, X-bedding. Well-cemented, rich in echinoderm debris
Calcaire de Blainville: Oolitic, often internal use , e.g. stair steps, perhaps inner pillars
Calcaire de Cruelly: Fine bioclastic, siliceous horizontal to oblique bedding, readily seen in monuments
Pierre de Caen: More homogeneous, siliceous lenses at the top not used. Some levels rich in small
pelletoids; microfossils very rare.
For examples of the use of French limestones in Sussex see:
https://www.nhbs.com/building-stone-atlas-of-sussex-book
https://www.nhbs.com/building-stone-atlas-of-sussex-book
For examples in Hampshire, West Sussex, East Sussex & Kent
see the respective Historic England County Building Stone Atlases https://www.bgs.ac.uk/mineralsuk/buildingStones/StrategicStoneStudy/EH_atlases.html
see the respective Historic England County Building Stone Atlases https://www.bgs.ac.uk/mineralsuk/buildingStones/StrategicStoneStudy/EH_atlases.html
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Normandy Middle Jurassic Limestone NJML
Coarse bioclastic grainstone-packstone Wimborne Minster Nave Columns
(images 2 x 2 cm)
Coarse bioclastic grainstone-packstone Wimborne Minster Nave Columns
(images 2 x 2 cm)
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Normandy Middle Jurassic Pierre de Caen NPdC
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For descriptions, photographs and locations please go to this excellent French site:-
http://geologie.discip.ac-caen.fr/index.htm
Select Jurassique > Bathonien > Formation
http://geologie.discip.ac-caen.fr/index.htm
Select Jurassique > Bathonien > Formation
