The Potential Geosite of the “Libeccio Antico” Quarries: a Sedimentological and Stratigraphic Characterisation of Ornamental Stone from Mt Cocuccio, Custonaci Marble District, Sicily

The Custonaci marble district of western Sicily is known for the production of a valuable ornamental stone that has been, and nowadays is exploited due to its suitable properties and aesthetic qualities. The “Libeccio Antico” was, among the “marbles”, the most appreciated ornamental stone during the Baroque Age (the XVII–XVIII centuries), due to its strong polychrome contrasts from ivory to yellow, green or dark red. This polychrome pattern is the result of dissolution processes that involved an Upper Triassic peritidal limestone. The varicoloured sediments in paleocavities, collapse breccias, paleosols and neptunian dykes that occur in the “Libeccio Antico” represent the peculiar characteristics that have given this stone its particular ornamental interest. This study provides an original sedimentological and stratigraphical analysis of the Upper Triassic carbonate succession in which most of the “Libeccio Antico” quarries occur. Petrophysic descriptions, accompanied by mineralogical and geochemical characterisations, are provided to comprehensively describe the diagenetic evolution of the carbonate host rock. This study emphasises as the “Libeccio Antico” represents a unique geoarchive among ornamental stones due to its origin, which involved diagenetic processes that occurred in a well-defined geological environment and over a restricted period of time. Moreover, this “marble” is frequently mentioned by architects, historians, naturalists and geologists in historical archives from the XVIII century in Sicily. All of these characteristics make the “Libeccio Antico” quarries a valuable geosite that should be promoted.