Jasper:
The Jasper body was first produced by Wedgwood and is still popular today throughout the world. It is also regarded as a vitreous earthenware body. In this body Barium Sulphate is used as a major Flux. The following is the common body recipe used throughout the wold:
Ball Clay - 26%
China Clay - 18%
Quartz - 11%
Barytes - 45%
All the raw materials are mixed in a ball mill to produce a liquid slurry. Depending upon the colour requirement different colour stains can also be added into the Ball mill during mixing. The prepared liquid slurry is passed through sieves and magnets, filter pressed and pugged in a pug mill to produce a homogeneous plastic body. The plastic body thus prepared can be pressed into various types of moulds, either made of plaster or wood or metal. If the shape is too much intricated, casting process can be employed. The formed shapes are fired at a temperature of 12500C to give a vitreous body that is just like made out of stone. It is widely used for making decorative high end products.
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