The dissolution of calcium carbonate polymorphs was investigated at conditions of constant undersaturntion at neutral pH, 25°C. The kinetics data suggested that the order of dissolution velocity is: aragonite < vaterite < calcite and the mechanism was controlled by surface diffusion. Treatment of the calcium carbonate polymorphs with inorganic orthophosphate in suspensions resulted in significant uptake of phosphate with the order aragonite > calcite vaterite. The calcium carbonates with phosphate uptake gave reduced dissolution rates but a stronger dependence on the solution undersaturation was exhibited in comparison with the untreated crystals.