Ceramics glossary.

The terms you will meet in quotes, spec sheets and sample reviews, in plain language.

Bisque: Clay that has been fired once, before glazing. It is hard and porous.
Bisque firing: The first firing that turns dried clay into ceramic so it can receive glaze.
Glaze firing: The firing that melts glaze into a glassy surface fused to the body.
Stoneware: A dense clay body fired to a high temperature. Durable and low in water absorption — the common choice for everyday and hospitality pieces.
Porcelain: A fine, white clay body fired very hot until it is highly vitrified and often translucent at thin edges.
Earthenware: Clay fired at lower temperatures. More porous and less chip-resistant than stoneware.
Vitrification: The point at which clay particles fuse into a glassy, less porous structure during firing.
Water absorption: How much water a fired body absorbs, used as a measure of vitrification and durability.
Glaze break: Where glaze thins over edges and rims, showing a lighter or darker tone than the main surface.
Pooling: Where glaze gathers in recesses, creating deeper colour.
Crazing: A network of fine cracks in a glaze surface, caused by a mismatch between glaze and body.
Pinholing: Tiny holes in a glaze surface, a defect checked for during quality control.
Foot ring: The unglazed ring a piece stands on. It is ground smooth so it does not scratch tables.
Rolled rim: A thickened, rounded rim that resists chipping and feels comfortable on the lip.
Fired-on decal: A printed transfer applied to a glazed piece and fired so it fuses with the surface.
Underglaze: Colour applied beneath a clear glaze, sealing decoration under the glassy layer.
Deboss: A mark pressed into the clay, such as a maker's or brand stamp.
MOQ: Minimum order quantity — the smallest production run quoted for a design.
Reference sample: The approved piece kept on file that production and reorders are checked against.
Leather-hard: Partially dried clay that is firm enough to trim and attach handles.