Free convective mass transfer at the individual surfaces and total surface of up-pointing truncated cones of different height and base diameter were experimentally studied using the limiting diffusion current technique. It was found that the mass transfer rate is highest for the upward-facing horizontal surface. The experimental mass transfer coefficient for the combination of downward-facing horizontal and conical surface is lower than that obtained from the equivalent summed separate surfaces due to the fact that the conical surface is exposed to solution which has already been depleted in cupric ions. The total mass transfer was successfully correlated using a single characteristic dimension (defined as a surface area divided by perimeter projected onto horizontal plane) which takes into account all the relevant dimensions of a truncated cone, i.e. the height and two diameters.