Ceramics Terminology

Vase - Lip/mouth

Top of vase

Vase - neck

Narrow connector to body of vase

Vase - body

main section of vase

Vase - foot

Bottom of vase

Four Stages of Clay - #1

Leather Hard:

• Still damp, fresh, workable

• Let it partially dry

• Bendable and can stick

Four Stages of Clay - #2

Green Ware/Bone Dry:

• unfired pottery that is completely air dried and ready to be bisque fired

• Clay is the most fragile here (like dust)

• Shouldn’t be worked with/moved around

Four Stages of Clay - #3

Bisque Ware:

• Clay has been fired one time; it is hardened

• It has changed color (pinkish) and is ready to glaze

• Will need to be fired one more time

Four Stages of Clay - #4

Stone Ware:

• Has been fired between 2,100-2,300˚F

• Has been fired twice

• Pots shrink 13% through two firings

Slab

Pressed or rolled flat sections of clay used in hand building, must be leather hard before assembly

Slip

Clay mixed with water, used as a glue in fusing slabs together and for decoration

Grog (grog content)

Fired clay ground into fine sand and mixed with new clay, gives extra support to loose clay for wheel throwing and produces specks in the clay body when fired unglazed

Plasticity

The quality of clay which allows it to be manipulated into different shapes without cracking or breaking

Bat

A flat disc made out of wood, plaster, or plastic which is used to support clay from the wheel or as it is being hand built

Rib tool

A rubber, metal, or wooden disc used to even clay

Callipers

A tool used to measure the diameter of round forms, for example, callipers are used to get lids to fit just right

Potters wheel

A device with either a manual (foot powered) or an electric rotating wheel head used to sit at and make pottery forms

Pug mill

A machine for mixing clay and recycling clay

Wedging

A method of kneading clay to make it homogenous by cutting and rolling, removes any air bubbles from the clay

Scoring/slipping

A method of joining two pieces of clay together: scratch the two surfaces, apply slip, and combine.

Centering

Technique to move the clay into a symmetrical rotating axis in the middle of a wheel so you can throw it

Coil

A piece of clay rolled like a rope, used in making pottery

Mold

A plaster shape designed to pour a slip cast into and let dry so the shape comes out as an exact replica to the mold

Composite pot/combo pot

Pots that were thrown or hand built in separate pieces and then assembled

Throwing

The process of creating ceramic shapes on the potter’s wheel

Raku

Translates to “enjoyment”, process of firing clay—take a ceramic and heat it very quickly (to 2,100–2,300 ˚F in around 45 minutes) and put it in a bin of metal/sawdust/combustible material to create an interesting pattern

Bisque fire

First firing of green ware/bone dry clays, without glaze

High fire

Second firing of bisque ware/bisqued clay, without glaze

Underglaze

A flat color added to green ware before a bisque fire, used for adding decoration, maintains the same color through firing

Glaze (matte or gloss)

A thin coating of glass and colored chemicals applied after the bisque fire and before a high fire, changes color during firing through a chemical reaction.

Dry-footing

To keep the foot or bottom of a pot free from glaze by waxing or removing the glaze

Fire/firing

To heat a clay object in a kiln to a specific temperature

Kiln

A furnace of refractory clay bricks for firing pottery and for fusing glass

Kiln furniture

Refractory brick posts and shelves used for stacking pottery in the kiln for firing.