The present paper studies the energy size relationship of minerals using a specially designed centrifugal crusher with rotation frequency control. The feed particles are accelerated by the rotating disc of the crusher and they crush on the opposite vertical wall having the predetermined specific kinetic energy. The mathematical modelling shows that the specific energy, energy per unit mass of the particles, is independent of their mass and is calculated to depend on the rotation frequency and the disc diameter. Crystalline limestone, marly limestone and serpentine samples are tested. The results obtained are used to present the energy–size relationship and to compare the crushing amenability of the rocks tested. A suggestion for further study is to derive the mathematical model of the breakage curves and to calculate the breakage energy for each size class using the model to be proposed.