Italy - limestone ECOS, Frome, Somerset
European Community Of Stone

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Large bivalve

Concentric ball mass of calcareous algae

About the rock: For Italy, there is this fine-grained ‘Perlato Marble’ This rock sits on the border line between limestone and true marble. Evidence for this is the presence of traces of fossil shell; fossils are destroyed by intense metamorphism. The brown shell fragments are parts of large bivalve shells but more prominent features are the concentric ball-masses of calcareous algae which stand out prominently against the grey background colour. The rock formed in a shallow sea where there was plenty of life. It has a hard calcite cement. This block, like others, shows the drill marks from the quarrying process.
For limestone to become marble it has to be changed by the heat and pressures of plate movement to be recrystallised. Most Italian marbles come from Carrara but this rock occurs several hundred kilometres to the south and did not receive the same intensity of heat and pressure as the Carrara region. The stone is early Cretaceous in age but, in character, it is quite different from the Chalk which is our time-equivalent.
Place of origin: The quarry source was the small town of Pontecorvo, some 80 miles south of Rome at the southern end of the province of Lazio. It lies on the foothill slopes of the Apennine range, close to Monte Cassino. The limestone was selected from the stock of the company Perlato Coreno Marmi.