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Global Heritage Stone: Belgian black ‘marbles’

Abstract The appellation ‘Belgian black “marbles”’ usually designates dark fine-grained limestones present in the Paleozoic substrate of south Belgium. They have been extracted mostly in Frasnian (Upper Devonian) and Viséan (Lower Carboniferous) strata, in various different localities (Namur, Dinant, Theux, Basècles, Mazy-Golzinne among others). Nearly devoid of fossils and veins, they take a mirror-like polished finish, with a pure black colour. These limestones were already known during Antiquity but were only intensively exploited from the Middle Ages. Many different uses were made of these stones, for architecture, decoration or sculpture, in religious or civil contexts, following all the successive styles, Romanesque, Gothic, Renaissance, baroque and so on. All these products, architectural, decorative and sculptural, were probably manufactured close to the quarries and were first exported to neighbouring countries (France and the Netherlands), then to all of Europe (Italy, Germany, Denmark, Poland, Baltic states, etc.) and, by the beginning of the nineteenth century, worldwide. They were always considered as high value-added objects, which allowed them to travel great distances from their origin. Thousands of references document the widespread use of these exceptional natural stones. They were employed, among other famous applications, as the black background of the Pietre dure marquetry of Florence. Some other lesser uses were either for musical instruments or lithographic stones. Today only one underground quarry exploits the black ‘marble’, at Golzinne (close to Namur). This prestigious material, with its dark aura, is suitable for recognition as a Global Heritage Stone Resource.