The Mt. Altissimo marbles (Apuane Alps, Tuscany): commercial types and structural setting

The Marbles sensu stricto of the Mt. Altissimo region form an important district in the central Apuane Alps and were exploited in many quarries active up to some decades ago. The marble varieties are characterized by high quality physical-mechanical properties often joined with very appreciated ornamental features (Tacca Bianca Statuary, Absolute white Porracci, Arabesque-like types, ecc.). At present only two large quarries are active. The most important is the Cervaiole quarry, SE of the Mt.. Altissimo, from which decorative Arabesque marbles are extracted; the La Buca quarry, Mt. Altissimo eastern slopes, has been reactivated a few years ago and shows high potentiality of development principally toward the underground production. The marbles here concerned crop out at the core of the Altissimo Syncline, one of the major megastructures of the Apuane Unit that formed during the D-1 compressional tectonics of the Tertiary orogenesis, and were severely affected by the D-2 tectonic phase. In the southern sector of the Altissimo Syncline, the closure of the megafold shows several kilometric-hectometric parasitic folds characterized by diffuse sheath style that controlled orientation and geometry of the following D-2 structures.