Calcium carbonate scale formation was simulated by the development in situ of
supersaturation in the vicinity of a stainless steel electrode immersed in a stable calcium
carbonate solution. The initiation of the growth of the supercritical crystals was accompanied
by a decrease of the absolute value of the cathodic current, which at the end of crystallization
was constant. The absolute final value of the cathodic current was the measure of the extent
of crystallization. In the absence of any additive the only phase identified on the electrode was
calcite.