Electrodynamic Sorting (EDX™), or variable-frequency eddy-current sorting, is an evolution of sorting technology aimed primarily at light-metal and aluminum alloy recycling. EDX™ is being developed by the Department of Metallurgical Engineering, University of Utah under an ARPA-E (Advanced Research Projects Agency – Energy) contract. From a purely physical perspective, the EDX system operates by generating an alternating magnetic field in the gap of a ferrite core. As the metallic particles pass through the gap, they are ejected at different velocities depending on their electrical conductivity and other properties. In this presentation we describe the fundamental physics of the phenomenon, simulation of magnetic field and velocity of ejection with CST software, optimal frequency for a given light metal or alloy mix, results in laboratory scale and pilot scale (100 kg/h) EDX systems. Finally, the results on auto shredder scrap mix is presented.