Ceramic products with crystalline structure on its body give an artistic effect. The usage of zinc oxide which acts as a flux material has a beneficial effect in many colored glazes amongst which is crystalline glaze. Samples are fired at different gloss firing temperature of 1200oC to 1250oC for half an hour and hold for five hours at crystal growth temperature. After firing, the morphology of crystalline structure on the ceramic substrate body was identified using visual observation. The result show crystals start to develop at 1230oC of gloss firing temperature. Scanning Electron Microscope (SEM) analysis shows that these crystals are made of acicular needle shape crystals. X-ray Diffraction (XRD) and Energy Dispersive X-ray Spectrometer (EDX) analysis of the phases identified these crystals as willemite, Zn2SiO4 which formed spherulites. The results also show obvious growth and distance distribution between each of spherulites as the gloss firing temperatures increase to 1250oC.