Analysis of the size–dependency of relevant mineralogical and textural characteristics to particles strength

•A characterisation method was developed to extract quantitative mineralogy and texture.•The characterisation information was simplified into seven indices.•The mineralogical and textural characteristics were analysed on different scales.•A size – independence was observed for most of the characteristics.•An increase in variability among particles is observed for most of the characteristics as size reduces.•The variation of ore characteristics in the different rock types indicates that no single characteristic controls particle strength.