To qualitatively describe the shape of particles, the observer is often content with a mere visual inspection, in the case of fine samples probably with the aid of a microscope. Characterizations like ”needle-shaped crystals”, ”compact granulate”, ”splintered grain”, or ”rounded sand” are quickly made and bring a corresponding picture to the mind of every reader. These descriptions are insufficient, however, when it comes to evaluating the suitability of a material for a specific application. If, for example, sand is intended to be used as a building material, the grains must not be too round. In this case, it is important to precisely quantify this roundness to reliably determine the suitability of the raw material. This is where quantitative particle shape analysis comes into play.