More than 100 different mineral species have been described from the marble cavities of the Apuan Alps (northern Tuscany, Italy). Among them, six minerals have here their type locality. These mineral specimens are a unicum in the mineralogical realm owing to their crystallographic beauty and rarity. The collaboration between professional mineralogists, photographers and mineral collectors has resulted in this work that represents the state-of-the-art in the mineralogy of the cavities of the Apuan Alps marble. The description of all the known mineral species (updated to the end of 2018) and of the main quarries, coupled with an incredible set of wonderful photos, make this book a reference text for the study of the treasures that Nature jealously enshrines in the marble cavities.