Methods and apparatus for combinatorial (i.e., high-throughput) materials research, such as catalysis research, that involves parallel apparatus for simultaneously effecting mechanical treatments such as grinding, mixing, pressing, crushing, sieving, and/or fractionating of such materials are disclosed. The methods and apparatus are useful for mechanically treating catalysis materials and other solid materials, including without limitation, electronic materials such as phosphors, colorants such as pigments, and pharmaceuticals such as crystalline drugs or drug candidates. The simultaneous protocols and parallel apparatus offer substantial improvements in overall throughput for preparing arrays of materials, such as catalysis materials.