Zirconium-based glaze is the most widely used opaque glaze due to its advantages of easy preparation,excellent performance and low cos.Zircon crystal with high refractive index and Mohs hardness can not only produce a high opacity,but also impart very good mechanical properties to the glaze.Therefore,understanding the crystallization mechanism and factors affecting the crystallization of zircon is important to opitimize the fabrication processes and the appearance and properties of the final products.