With the introduction of the rheological and surface tensiometry approaches,
peloids started to be viewed as a geological complex system that needed to be characterized in
an integrated way. The development of the Rossi factor revealed variations in the surface free
energy of Euganean thermal muds as a function of their quality, conformity, and matura-tion
degree. The Rossi factor consents to measuring the contact angle of Fomblin HC/25PFPE
Polyperfluoromethylisopropyl Ether by static sessile drop method. The de-velopment of the
Kinetic Contact Angle sessile drop methodology, applied to the meas-urement of Fomblin
HC/25 PFPE contact angles over time, led to the determination of an integrated surface
tensiometry parameter for the evaluation of the maturation process of Euganean thermal
peloids, here called the Maturation Mud Index. The Mud Maturation Index is based on the
contact angle measurements performed onto peloids surfaces col-lected by Osservatorio
Termale Permanente of University of Padova from 2005 to 2010. The Mud Maturation Index
has shown a connection to the activity of thermal spas during their pelotherapy season. As a
result, this index can serve as a valuable tool for surface tensiometry in assessing the
maturation process quality of a peloid based on its level of maturation within the thermal
activity of the Euganean Thermal Area in Padova, Italy
