Comminution is the process of reducing the particle size of mined ore through mechanical crushing, grinding, or milling, with the objective of liberating valuable mineral particles from the surrounding gangue (waste) material so they can be recovered by downstream beneficiation processes. Comminution is one of the most energy-intensive and costly steps in mineral processing, accounting for up to 50 percent or more of total plant energy consumption in operations such as gold, iron ore, and diamond processing. In bauxite mining, comminution may involve scrubbing and mild crushing to disaggregate soft, friable ores rather than intensive fine grinding. In gold processing, multi-stage crushing followed by ball or SAG (semi-autogenous grinding) milling reduces ore to a fine slurry suitable for cyanide leaching. For iron ore, comminution circuits produce particles fine enough for magnetic separation or flotation to separate magnetite or hematite from silica gangue. In diamond operations, careful comminution design is critical to avoid fracturing or damaging large, high-value diamond crystals. Optimising comminution circuits — through equipment selection, circuit configuration, and process control — is central to improving mineral processing plant productivity and energy efficiency.
