There are many forming techniques to make pottery, but one example is casting. This is where slip or, liquid clay, is poured into a plaster mold. The water in the slip is drawn out into the walls of the plaster mould, leaving an inside layer of solid clay. Which hardens quickly. When dry, the solid clay can then also be removed. The slip used in slip casting is often liquefied with a substance that reduces the need for additional water to soften the slip; this prevents excessive shrinkage which occurs when a piece containing a lot of water dries.
Slip-casting methods provide superior surface quality, density, and uniformity.