Progressive nucleation of copper on glassy carbon is examined by means of combined "current-time", i(t), and "number of nuclei-time", N(t), experiments performed at constant overpotentials. Information is obtained on the most important nucleation and growth parameters: the nucleation rate of copper clusters, the charge transfer coefficient, the exchange current density at the "copper-solution" interface boundary and the diffusion coefficient of copper ions. The copper ion's discharge is considered as a two-stage electrochemical reaction and the growth current of the supercritical copper crystals is interpreted in terms of the theory of progressive nucleation and growth under combined charged transfer and diffusion limitations. (c) 2006 Elsevier Ltd. All rights reserved.