Mined ores mainly consist of blasted rock pieces in which the valuable mineral fraction is dispersed with other minerals and gangue. These large rock pieces must first be crushed to liberate the mineral particles from gangue. Comminution refers to the different processes used to break a large mineralogical sample into fine particles. It involves operations like crushing, milling, grinding, cutting, and vibrating. The milled ore is then subjected to a series of separation processes to produce a concentrate fraction and a tailings fraction that is discarded. This chapter provides a brief overview of the typical comminution and concentration processes used in the critical mineral industries. Finally, the role of additive manufacturing in these mineral processing operations is envisaged and summarized.