Magnesian Limestone. A dolomite rich rock from the Permian formations of North Yorkshire.
Magnesian Limestone, a complex succession of limestones of differing compositions and textures which formed beneath the waters of the Zechstein sea, about 240 million years ago during the Permian period. At this time the UK was positioned in a more tropical latitude. This limestone contains high concentrations of the Magnesium rich mineral – dolomite CaMg(CO3)2. Characteristic fauna which exploited the environment that this limestone formed in included bryozoans & stromatolites. This example was sourced around Tadcaster in North Yorkshire. Each specimen is supplied in a labelled card tray.