A bench-scale extraction cell has been developed, in which agitation is provided by two rapidly vibrating plates which induce controlled circulation in each phase without disturbing the liquid-liquid interface. Copper has been extracted from the lower aqueous phase into a kerosene solution of di-(2-ethyl hexyl) phosphoric acid, under varying conditions of temperature, agitation, and composition. The rate process appears to be diffusion controlled. Limited data on copper extraction by LIX-63 are also presented.