France - limestones ECOS, Frome, Somerset
European Community Of Stone

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Water-worn limestone

These two rocks are both limestones;
the base rock is known as ‘Napoleon marble’

About the rocks: From France there is a contribution resembling a giant doughnut perched upon a squared plinth. The top rock is water-worn and is of Devonian age. These limestones just across the Channel from Dover could be thought of as a distant extension of the fold structures which run east-west through the Mendips beneath Frome and extending beneath Wessex and the Weald to re-emerge in France. The smoothed surfaces were caused by erosion from groundwater solutions.
The base rock is the well-known ‘Napoleon Marble’, a shallow-water algal limestone of Carboniferous age. This type of rock has been described as ‘porcellanous’ or ‘chinastone’, the outcome of shallow water marine conditions in which algae played an important rock-forming role. It is not a true metamorphic marble, but a hard sedimentary limestone. However, in many city centres, polished, it has the character of ‘marble’, taking and retaining a high surface finish and revealing cloudy outlines of calcareous algae.
It has the name Napoleon Marble for historic and sentimental reasons. It was on the cliff tops nearby that the Emperor marshalled his Grande Armée for the projected invasion of England before his better judgement made him call off the venture. The French celebrate the occasion with a monument on the cliff top and the naming of this limestone. 		Place of origin: The top rock comes from the limestone quarries of Ferques in the Boulonnais of northern France. Ferques can almost match Frome in is dependence upon stone quarrying for its prosperity and sense of history; it even has a museum of quarrying. The block base is a different limestone from the same area between Calais and Boulogne.