Stoneware

Stoneware is the workhorse clay body of most functional pottery, chosen for mugs, plates, bowls, and anything else expected to survive years of daily kitchen use. Fired to a mid to high range, typically somewhere between cone 5 and cone 10 depending on the specific clay, stoneware vitrifies, meaning the clay particles fuse together tightly enough that the fired body becomes hard, dense, and only very slightly porous, sometimes effectively watertight even without a glaze on the interior.

That density is what gives stoneware its reputation for durability and its friendliness to everyday use, since a vitrified body resists chipping and absorbing stains far better than earthenware, and it tolerates the thermal shock of a dishwasher or microwave more gracefully. Stoneware clay bodies also come in a wide range of colors and textures, from smooth and pale to heavily speckled or dark and iron rich, and many are formulated with added grog, small fired clay particles, for extra strength and workability on the wheel.

Buying stoneware means checking the specific cone range printed on the bag or listed by the supplier, since firing a cone 10 stoneware only to cone 6 leaves it under matured and more porous than intended, while pushing a cone 6 body to cone 10 can cause it to slump, bloat, or warp. Matching glazes to the clay's actual firing range matters just as much as matching the clay to the kiln, and most stoneware potters keep a small library of test tiles for exactly this reason before committing a full batch of pots to a glaze they have not verified.