Ceramic Quartz

The traditional ceramic body is based on the clay, feldspar and quartz triad. Clay provides the plasticity that makes shaping possible, feldspar acts as the flux that forms the glassy phase during firing, and quartz provides the skeleton of the body. Quartz grains limit excessive shrinkage during drying and firing, reducing the risk of warping and cracking. In the fired product, quartz remains dispersed within the glassy phase and acts as a filler that supports mechanical strength.

In glaze and engobe recipes quartz builds the backbone of the glaze as the SiO₂ source. The quartz content of the glaze directly affects surface hardness, scratch and chemical resistance, gloss and the coefficient of thermal expansion. If the expansion of the glaze and the body are not matched, crazing or shivering appears on the surface; the amount of quartz in the recipe is adjusted to establish this balance. Glaze quartz is therefore expected to offer both chemical consistency and batch-to-batch consistency of fineness.

When a white fired color is targeted in ceramics, the impurity content of the quartz becomes decisive. Compounds containing iron and titanium can cause specks and color deviation on the surface after firing, so low-iron, washed raw material is preferred. Grinding fineness also affects the reaction rate and surface quality: micronized quartz is used in glazes and fine bodies, while granular quartz is used in coarser bodies and technical applications. The fineness and fraction suited to your application are selected according to your production conditions.