The basic raw material for making any ceramic product is clay and that could be of several types - china clay, fire clay, ball clay etc. Clay in powder form is sourced from Rajasthan and Gujarat. It is mixed in varying proportions with other raw materials to make clay that is ready-to-use. This is done in-house and the mix is churned in large machines. After this it goes to the filter press that makes cakes (discs) of clay and removes impurities. This is further rolled out through an electric pug-mill and becomes void of any kind of air bubbles, ready for casting.
Commonly used clay types while making Khurja include:
• Stoneware : 50% ball and china clay, 50% stone (25% quartz, 25% feldspar)
• Bone China: 50% ball and china clay, 50% bone ash (calcium phosphate)
• Porcelain : Quartz, feldspar and china clay
The choice of clay depends on temperature of firing, desired quality and finish of the product.
