Slab

A slab is clay rolled or pressed flat to a consistent thickness, typically somewhere between about half a centimeter and a full centimeter depending on the piece, then cut into shapes and assembled into three dimensional forms. Slab building sits alongside wheel throwing and coil building as one of the core ways potters form pieces, and it naturally favors angular, geometric, or architectural shapes that would be difficult or impossible to achieve on a spinning wheel.

Getting an even slab is the technical foundation the whole technique depends on, since an uneven slab with thick and thin patches will warp, crack, or dry unevenly once assembled into a box or dish shape. A slab roller, guide sticks, or careful rolling pin work with wooden strips on either side all aim at the same goal, one uniform thickness across the entire sheet, and texture mats or fabric pressed into the surface before cutting add pattern without affecting that thickness.

Once cut to shape, slabs need to reach a soft leather hard stage before joining, using the same score, slip, and press technique used for handles, and edges are often beveled at an angle rather than cut straight so two pieces meet with more surface area for a stronger bond. A frequent slab building mistake is assembling pieces while still too wet, which sags and distorts joints under its own weight, or letting a finished piece dry with one side exposed to air and the other trapped against a table, warping it as it shrinks unevenly.