Page 18 - Curriculum Visions Dynamic Book

The suspension is poured into a mould that is made of a porous material like plaster. The water is sucked from the clay into the plaster, and the clay then gains solidity and can be taken from the mould and fired.
Firing
The heating of ceramics to make a hard, strong material is called firing. Firing uses lots of heat, and it would be wasteful to also use this heat to dry as well as harden the ceramic. The first stage after moulding or casting
is therefore for the article to be left to stand in order to dry in the air for a while. This can be speeded up by using low-temperature ovens and fans.
There are two kinds of water associated with clays. One kind is the water between the clays. In dry air it will evaporate. The second kind is water contained
(Above) The clay suspension is poured into casts made of plaster, and the excess drained off. Once enough moisture has been taken from the body of the clay, the object will have enough rigidity not to deform under its own weight, and the cast can be removed. The clay is then ready for firing.
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