Ceramics Vocabulary List A

Clay

A compound of decomposed and altered feldspathic rock consisting of aluminum along with non-plastics, suck as quartz, and organic matter

Porcelain Clay

Pale body of primary clay with a distinctive ring when struck.

Stoneware clay

Secondary clays that aren’t as fine-grained as other clay bodies.

Absorption

The capacity of a material to soak up liquid.

Shrinkage

Contraction of the clay or glaze and either drying or frying

Slip

A suspension of clay in water

Grog

Fired clay that has been crushed into granules which may be added to clay body to increase strength control drying and reduce shrinkage.

Plasticity

The quality of clay that allows it to be easily shaped and maintain its form.

Leather-hard

The condition of raw clay when most of the moisture has evaporated leaving it still soft enough to be carved or joined to other pieces.

Bone Dry

The condition of unfired clay that has no assorted moisture other than natural humidity. The form is ready to bisque fire.

 

Bisque ware

Clay that has been fired once, unglazed.

Blowout

The explosion of clay in the kiln caused by the sudden escape of steam resulting from rapid heating of thick clay or the presence of impurities. 

Blistering

Air bubbles appearing in a glaze after a fast firing.