From ancient times, ceramists [SAYR a mists] have made hollow vessels as practical containers. Such practical vessels are often called “pots.” Pots are made to be functional. They have been used to hold everything from water to wine, from ice cream to soup, from seed grain to the ashes of ancestors.

Earth rich in clay must be soaked in water and strained to remove sand, decaying vegetable and animal matter, rocks, or other debris before it can be used in ceramics. The potters of Mata Ortiz, Mexico find local clays of different colors in the region surrounding their village. This is a sample of that clay as it comes from the ground and as it appears in a finished pot.

Clay particles are very fine. Here you can see the clay dust made after sanding a pot and how it returns to a malleable state [a state in which it can be pulled and pressed and formed by hand] when water is added.

When fired to high temperatures air bubbles in clay will expand and can explode the clay around it. Ceramists remove air by wedging clay rather as bakers kneed bread dough. Wedging also homogenizes (mixes evenly) the clay.

Ceramists use a variety of processes to form clay into vessels and other ceramic pieces. They make pinch pots by starting with a ball of clay. They press a hole in the center with their thumbs, and continue to pinch and squeeze the sides to form a pot.

Another way to construct a pot is to roll a slab, with a rolling pin or with a machine like this one ...	... cut out pieces with a pin tool, ...
... score or roughen edges, ...	... coat edges with watered-down clay, called slip, ...
	... press edges together, ...
... and paddle seams.

The scoring helps join the surfaces. The slip helps “paste” one surface to another. Without scoring and slip, as the clay dries, the pieces held together only with moisture fall apart.

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