Ribs (clayworking tools)

Refers to a type of potter's tool; ribs are curved pieces of wood or bone, characteristically having one flat and one curved edge. Ribs are used for shaping, curving, smoothing, trimming, or opening wet clay; they give the profile of the outside of a plate or pot. One hand presses outwards and upwards on the inside of the worked clay, while outside the rib is used to create a smooth surface.