Using glycine as an additive and choosing different solution heights in the vessel. we can control the precipitation or calcium carbonate crystals on glass-clips with their polymorphs to he calcite vaterite or aragonite. Then we tried to establish the causalities between experiment conditions and polymorphs on the aspect of nucleation energies. Qualitative analysis showed approving interpretation of results of the experiments, Further discussion summarized three ways in which additives may control polymorphs in biomineralization. (c) 2005 Elsevier B.V. All rights reserved.