The weathering of the Mt. Prinzera serpentinites (Parma province, Northern Apennines, Italy) produced dominant smectite and minor Fe-hydroxides. The mobility of the elements during weathering has been estimated using the ratio K i = M Si /M Ri , where M i indicates the mass of a generic component i before (R) and after (S) the weathering, and using TiO 2 as a practically immobile component. For prevalently to tendentially mobile elements, the degree of mobility, which in our case increases as K i decreases, is in the order Mn nearly equal Cr = Fe < V nearly equal Zn nearly equal Co < Ni < Si < Mg < Ca. The elements Ti, Ga, Al and Zr are prevalently immobile. The mass chemically removed by the circulating waters during weathering may reach very high values (on average 52% of the original mass of serpentinite) and the main contribution to the mass loss is due to Si and Mg. The composition of the perennial and ephemeral springs in the area is in agreement with the degree of the element mobility at least for Cr, Mg and Ca.