Beer Stone – Upper Cretaceous Limestone ( lead author :WGT)
Beer Stone is a gritty-textured, bioturbated calcareous freestone which occurs near the base of the Upper Cretaceous White Chalk Sub-Group (Turonian age). It is known only from quarries 1.5km NW of the coastal village of Beer in SE Devon. The gritty texture of Beer Stone is not due to the presence of angular quartz sand, it is a chalky calcarenite comprising bivalve fragments, foraminifera and echinoderm debris. The stone is white to pale cream-coloured (buff) when fresh, becoming grey on exposure. |
Beer Stone in the quarries (Beer Quarry Caves) near Beer is 4-6 metres thick (13-20 feet). It was worked by the Romans, Saxons and Normans onwards. Beer Stone was used extensively in Exeter Cathedral and Winchester Cathedral, as well as many buildings in SE Devon and SW Dorset. Although an excellent freestone for interior use it is not very durable and external weathering usually reveals trace fossils (crustacean burrows) with a crumbly white matrix.
Charmouth Parish Church (St Andrew’s, rebuilt 1836-8) has a Forest Marble plinth, Chert rubble walls and Beer Stone window dressings and quoins showing burrows (bioturbation). More-recently weathered examples are seen in the shelters above the beach at Beer (see image to right).
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Below updated by WGT April 2019
Thanks to Beer Quarry Caves General Manager John Scott, FRSA, FRGS, fresh samples of Beer Stone from four levels (beds) were made available for study in 2018.
http://www.beerquarrycaves.co.uk/beer-stone/
Thanks to Beer Quarry Caves General Manager John Scott, FRSA, FRGS, fresh samples of Beer Stone from four levels (beds) were made available for study in 2018.
http://www.beerquarrycaves.co.uk/beer-stone/
Top Bed: Bioclastic Packstone
Upper Middle Bed: Bioclastic Packstone
Lower Middle Bed: Bioclastic Grainstone-Packstone
Similar to but finer-grained than the Base Bed. Well-sorted very fine to medium shell debris and chalky micrite. Rare very fine quartz and glauconite grains. Some foraminifera 0.5-1mm. Burrows clearly visible.
Similar to but finer-grained than the Base Bed. Well-sorted very fine to medium shell debris and chalky micrite. Rare very fine quartz and glauconite grains. Some foraminifera 0.5-1mm. Burrows clearly visible.
Base Bed: Bioclastic Grainstone-Packstone
Well-sorted medium to coarse echinoderm debris and chalky micrite. Rare very fine quartz and glauconite grains. Some dark organic matter. Burrows 5-10mm diameter. Some syntaxial cement.
Well-sorted medium to coarse echinoderm debris and chalky micrite. Rare very fine quartz and glauconite grains. Some dark organic matter. Burrows 5-10mm diameter. Some syntaxial cement.