Potato tubers of Ibis and Lawina cultivars frown on midium-heavy soil, as well as the stones and earth clods from the same potato field, were examined for geometrical shape and overall dimensions. Elongation and flattening factors were determined for all examined objects as well as the mass index of overall dimension filling. Values of maximum projection area on the surface for either, potato tubers, stones and earth clods were measured. Significant differences regarding the amounts of examined features among potato tubers and typical impurities of harvested potato crop were observed.