Different concentrations of TiO 2 and ZrO 2 were incorporated in Li, Ba aluminosilicate glass to establish their effects on the crystallization process. The kinetics of phase transformations, the final crystalline phase assemblages and the microstructures formed were found to be dependent on the types and concentration of the nucleant involved. The presence of ZrO 2 and TiO 2 were found to enhance the crystallizability of the glass. ZrO 2 is much better than TiO 2 in promoting homogeneous nucleation and growth of extremely fine-grained microstructure of β-eucryptite ss and hexacelsian. ZrO 2 retarded the formation of β-spodumene ss and monoclinic celsian. TiO 2 in low concentrations greatly facilitates the crystallization process and favors the transformation of β-eucryptite ss → β-spodumene ss and hexacelsian → monoclinic celsian.