The effect of high-energy ball milling on calcium fluoride was studied by X-ray Diffraction (XRD) Line Profile Analysis (LPA) and Solid State Nuclear Magnetic Resonance (NMR) spin-lattice relaxation. The latter technique is especially useful not only to detect the nonhomogeneous effects of the early stages of mechanical grinding, but is also sensitive to the defect structure of the ball milled powders. When supported by Solid State NMR, XRD LPA unveils fine details of the milling effects on fluorite, in terms of increasing dislocation density and progressive refinement of the crystalline size down to the nanoscale. (C) 2012 Elsevier B. V. All rights reserved.