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 temperature (1200 – 1250oC) for half an hour and hold for five hours at crystal growth temperature (1060oC). After firing, the morphology of crystalline structure on the ceramic substrate body is identified using visual observation. The phases present are identified through X-ray diffraction (XRD). The results show obvious different spherulites pattern although being hold at gloss firing temperature for half an hour only. As the temperature increase, willemite crystals that consist in the spherulites are also increasing
