The surface properties (i.e. the values of the Lifshitz-van der Waals (γ L W ) components and Lewis acid (γ + ) and base (γ - ) 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 γ L W , γ + and γ - for these solids tend to change after grinding; γ L W and γ - decreased for all these solids and γ + often increased, depending on the material.