gas 11 which is divided by the cone 12 and flows through the concentric slot 13 coarse or difficult to disperse solids 14 leave the dispersing space through the slot and are deposited in the collecting vessel 15 fine or easy to disperse solids 16 leave the dispersing space together with the exhaust air stream via the fines exhaust air exit 18 fines and exhaust air are separated in downstream conventional separator units by means of the process according to the invention and the classifier jet mill according to the invention it is possible to effect specific control of the residence time of and the stress on the solids by supply of an adjustable secondary gas stream via the slot the secondary gas stream alters the exit probability into the collecting vessel and shifts the separating limit within the dispersing space toward coarser values furthermore a continuous removal of the coarse or difficult to disperse portions through the concentric slot of variable width into the collecting vessel is possible for continuous operation this collecting vessel can be replaced by a cone equipped with a suitable discharge element for example an impeller wheel this makes it possible to affect the comminution and separating effect within wide limits not only by variation of the grinding gas pressure the grinding gas flow rate through the grinding ring and various nozzle geometries from round to slot like but also by the supply of secondary.