This is the Frosterley marble once it is cut, polished and mounted.  As well as creating free standing sculptural forms from Frosterley marble I also produce purely decorative bespoke objects  that can be made to order    
A  Frosterley marble bowl carved from a glacial boulder
app 40cm across.
Frosterley Marble
Quarrying has been carried out in Frosterley since the 13th century and continues today.  Frosterley is not a true marble but a black limestone that is speckled with the remains of prehistoric plants and marine creatures.  The rock dates from the carboniferous period, some 325 million years ago. When cut and polished, Frosterley marble forms an attractive and ornate stone,  that was once prized throughout the UK, a good example can be found in Durham Cathedral which has some fine interior columns.
About 325 million years ago, during the Carboniferous period, a warm shallow sea covered much of North East England. In the clean sunlit waters a variety of marine animals lived and died.  Colonies of Dibunophyllum Bipartitum, a species of coral, were locally very abundant.  After death their stoney skeletons littered the seabed and were eventually covered in a grey ooze which hardened over time into limestone.  
Close up Photograph of the fossilized coral Dibunophyllum