### Rock Crushing Rule of Thumb - Mineral Processing & Metallurgy

Nearly all crushers produce a product that is 40% finer than one-half the crusher setting. Source: Babu and Cook; The product of a jaw crusher will have a size distribution such that the -80% fraction size (d80) is slightly less than the open-side setting of the crusher. For example, if the open- side setting is 6 inches, the d80 product size will be 5¾ inches.