Abstract: A novel particle sorting system based on vibrations induced by impact against a strike plate is disclosed, wherein two strike plates in succession are used, the first to absorb kinetic energy from certain particles on a preferential basis due to particle composition, and the second to absorb the residual kinetic energy for analysis. Vibrations arising in the second strike plate due to particle impact which meet preset criteria corresponding to undesired particles are used to actuate an ejection system which sends an impulse to the offending particle, deflecting it from its otherwise undisturbed trajectory. Also disclosed is an analyzing circuit which combines two or more waveform features of the vibration signal in an algorithm such as a ratio, to provide an unusually high sensitivity for discrimination among the particles.