Spherical polycrystalline particles of Na4Zr2Si3O12 (NZS) have been prepared by a mist pyrolysis technique with alkoxide ethanol solution, Firing the precursor particles, obtained by pyrolysing at 550 degrees C, yielded the NZS with the highest S/N ratio and the least second phase at similar to 1000 degrees C. Each spherical particle with an average size of similar to 0.5 mu m was composed of primary particles of 0.1 mu m diameter after firing. Comparing the particle formation process with the sol-gel, alkoxide pyrolysis and the aqueous solution processes, it would appear that the primary particle size of the mist-pyrolysed NZS depends on the size and residual alkyl group content of the precursor polymers.