Luxembourg -
ECOS, Frome, Somerset
European Community Of Stone

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Calcareous sandstone?

About the rock: When it arrived this rock was called a sandstone but is it a sandstone or a limestone? Is bedding across or down the length of this 2.5m block? It is believed to be Tertiary in age.
Luxembourg’s solid geology is thickly mantled by deposits of cover-sands laid down when the Baltic ice sheets melted and sent millions of gallons of meltwaters to the North Sea Basin. Locally, those loose sands could be consolidated when mineral-rich springs bonded the grains into a tough sand rock. If the springs were silica-rich, sarsen is the resulting rock; hard and flinty, perhaps one of the toughest of rock types. BUT, limestone shell debris can be seen within this block and it does react with dilute hydrochloric acid indicating that the cement is not silica but calcite. Perhaps it should be called a calcareous sandstone.
Place of origin: At the moment, its exact place of origin is unknown. Please contact us if you can help. Luxembourg is known mainly for its Jurassic strata and limestone. The stone sent to Frome, however, is simply called ‘sandstone’.