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How does clay help shape whiteware before firing?

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traditional ceramics Stages in the slip casting of a thin-walled whiteware container. Clay powder is mixed in water together with a dispersing agent, which keeps the clay particles suspended evenly throughout the clay-water slurry, or slip. The slip is poured into a plaster mold, where water is drawn out by capillary action and a cast is formed by the deposition of clay particles on the inner surfaces of the mold. The remaining slip is drained, and the cast is allowed to dry partially before the drain hole is plugged and the mold separated. The unfinished ware is given a final drying in an oven before it is fired into a finished product.

In the production of whiteware, clay serves as the essential plastic component that provides the necessary workability to shape the product before it is fired.1

This shaping ability is derived from the fine, platy morphology of clay particles, which allows them to slip over one another when the material is mixed with water. Depending on the water content, the clay-water mixture can be adjusted to be stiff or plastic, enabling various forming techniques such as pressing, extrusion, or jiggering. When higher water content and dispersing agents are added, the clay forms a suspension known as a slip, which is used in slip casting to create complex shapes like plumbing fixtures. By providing this plasticity, clay allows manufacturers to mold raw materials into precise, useful forms that maintain their integrity until they are hardened in the kiln.213