Shear along rock faults is always associated with wear of the sliding blocks that commonly results in the production of fine powder called gouge. We experimentally analyzed intensity of wear-rate and frictional strength during shear of dolomite and granite samples at slip-velocity of V = 0.001-1.0 m/s, and normal stresses of σn = 0.25-4.5 MPa. The experiments showed that the friction coefficients of these rocks depend on the mechanical power-density, which is the rate of energy dissipation during slip. The wear-rates, WR, showed dependency on the mechanical-impulse of the form WR = a · [τ/V]b where τ is shear stress, V is the slip-velocity, and a and b are material constants. This relation of wear-rate to loading indicates that for rocks, the Archard (1953) model is only a special case for low slip-velocity. We propose here a model based on microfracturing wear at stressed asperities that explains the observed dependency of wear-rates on the mechanical impulse.