Comminution is the reduction of solid materials from one average particle size to a smaller average particle size, by crushing, grinding, cutting, vibrating, or other processes.
[1][2] In geology, it occurs naturally during faulting in the upper part of the Earth's crust.
[3] In industry, it is an important unit operation in mineral processing, ceramics, electronics, and other fields, accomplished with many types of mill.
Within industrial uses, the purpose of comminution is to reduce the size and to increase the surface area of solids.
Primary crusher products in intermediate feed particle size ranges (100mm > P80 > 20mm) can be ground in autogenous (AG) or semi-autogenous (SAG) mills depending on feed properties and application requirements.