3rd phase: it corresponds to the “Bucine Sands” period (a term that is now falling into disuse). These sands were a river deposit formed by the Arno River. From bottom to top we firstly discover limestone conglomerates, secondly different sands and finally clay mire. In these deposits, which are relatively recent, lied the majority of the fossils exhibited in Bucine secondary school (case 2, 7, 8, 9, 10). In this epoch, man made his appearance in the Upper Valdarno. Man presence is not witnessed, as we may reasonably suppose, by a marked increase in fossil findings but, instead,  through an augmentation in litic handiworks (case 12). This third phase in the sedimentation process of the Upper Valdarno is marked by the continuous alternation between hot climate periods and cold climate ones. The mammal finds discovered in these deposits confirm this theory: elephant (hot climate), mammouth (cold climate),  rhino, ox, deer, bear.MORE>>