The surface properties (i.e. the values of the Lifshitz-van der Waals (gamma(LW)) components and Lewis acid (gamma(+)) and base (gamma(-)) parameters) of talc, calcite, dolomite, silica and zirconia, untreated and as ground powders, were determined by contact angle measurements (directly on flat surfaces and by thin layer wicking for powders). The values of gamma(LW), gamma(+) and gamma(-) for these solids tend to change after grinding; gamma(LW) and gamma(-) decreased for all these solids and gamma(+) often increased, depending on the material.