A method of sorting mined material to separate the mined material into at least two categories is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating particles depending on the susceptibility of the material in the particles. The method also comprises allowing sufficient time for heat generated in the particles to be transferred through the particles so that the surface temperature of the particles is a measure of the mass average temperature through the particles. The method further comprises thermally analysing the particles to detect temperature differences between particles which indicate composition differences between the particles; and thereafter sorting the particles on the basis of the results of the thermal analysis.