Electrophoretic mobility measurements of coal and pyrite particles in distilled water revealed a difference between the migration speeds of the two materials toward the anode in a d.c. electric field. This information led to the development of a laboratory electrophoresis column for spearating fine pyrite from coal by utilizing the electrokinetic and the specific gravity differences between coal and pyrite. The study demonstrated on a laboratory scale that pyrite and other impurities can be separated from fine coal be electrophoresis using a stage separation technique. After the initial success of the laboratory electrophoresis column, attempts were made to refine the apparatus and several scale-up techniques were considered. This work, however, was halted pending an economic evaluation of the process. Although the evaluation showed the process to be impractical for commercial coal preparation, it is believed that the electrphoresis column may have some application as a laboratory device.