The extent of CaCO 3 growth inhibition depends on the concentration of additive Ca 2+ ions relative to the volume of precipitates, and the solution pH. Above its isoelectric point, CaCO 3 surface becomes negatively charged, allowing for the adsorption of the positivelycharged additive Ca 2+ ions. This selective adsorption process is more effective for growth inhibition and synthesis of submicron particles in high alkaline conditions. The results show that a high pH condition does not produce high growth inhibition, except in the presence of additive Ca 2+ ions, and vice versa.