UK - Portland limestone ECOS, Frome, Somerset
European Community Of Stone

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Jurassic Portland Limestone

Chert nodule within the limestone

One of the many bivalve fossils

About the rock: This is an Upper Jurassic limestone (c.145 millions old) which formed in a warm, shallow sea. Many fossils can be seen easily. Layers rich in shells pick out the bedding in this oolitic limestone. The block has quarrying marks on the sides; evidence of traditional methods of extraction from the massive beds of rock. Place of origin: This 4m high, 12 tonne rock was supplied from the quarries of ARC Wessex on The Isle of Portland, Dorset. It is regarded by many as the UK’s best building stone; the familiar pure, white stone of civic buildings and war memorials throughout the country.