The crystallization of CaCO3 was done by gas diffusion method in aqueous solution using an insoluble layered of Al doped Bi2O2CO3 as crystallization director agent and CaCl2 and (NH4)2CO3 as source of Ca2+ and CO3 2- ions, respectively. The characterization by X-ray diffraction of polymorphs CaCO3 allowed identifying the formation of the calcite, aragonite and vaterite polymorphic phases. The aragonite metastable phase was obtained in low concentrations, while the vaterite metastable phase was obtained with the rising of Bi2O2CO3:Al particles in the reaction.