Clay TerminologyCeramics Unit

ClayA mixture of

different types of clays and

minerals for a specific ceramic

purpose.

Plastic

The condition of the clay where it is neither too wet

nor too dry to work.

Leather hardStage of the clay between plastic and bone dry

(green).This is the best time for carving

and burnishing clay.

Greenware (bone dry)

All ceramic ware prior to firing that is

totally dry.

All of the moisture has evaporated from the clay. It will feel warm to the touch.

BisquewareA piece of ceramics that has been fired

once at a low temperature (1850 degrees) to remove

all the moisture from the clay body and to make handling easier

during the glazing.

GlazeGlaze is a layer or coating of liquid clay materials and minerals which is then fired

to fuse it to a ceramic object to color, decorate,

strengthen or waterproof it.

produces a hard, vitreous, glassy surface. The glaze

may be transparent or opaque, clear or colored.

GlazewareA completed

piece of pottery or ceramics with

glaze on it.

Pinch TechniqueUsing hands and fingers to pinch

and thin out clay to the

desired thickness and

shape.

Coiling TechniqueA method of

forming pottery or sculpture from rolls of clay melded together to create the

walls.

Slab techniqueUsing thin

(1/4”) pieces of clay that have been rolled out

flat.

KilnA furnace or

an ‘oven’ built of heat-resistant

materials for firing pottery or sculpture.

FiringHeating the pottery or

sculpture in a kiln or open fire to bring the clay

or glaze to maturity.

Firing RangeThe range of temperatures at which clay

becomes mature or

glaze melts.For us it is

1850o

Bisque fireThe firing in which the temperature

is brought up to a point just before vitrification sets

in, around 1850o. This is cone 04

Glaze fireThe firing during which the glaze materials melt

and form a glassy coating on the

clay body sealing and protecting it.

ReprocessingReclaiming clay that is

either too wet or dry to be worked with.

If to dry- It must be soaked in water until it breaks up and then it is poured onto plaster slabs to be dried to the proper consistency for

reuse.If to wet- it is laid out on

plaster slab to dry a bit for workablility.

Slip (Engobe)Clay that is at a

mayonnaise consistency.

Used to attach two pieces of

clay together or to add

decorative details.

ScoreIs to roughen

up the surface by scratching with a sharp object so two pieces of clay

attach together better.

WedgeMethod of kneading

clay (similar to kneading bread

dough) to get rid of air bubbles, lumps,

and prepares a homogeneous

material.

SgraffitoDecoration

produced on pottery or ceramic

by scratching through a surface

of plaster or glazing to reveal a different color underneath.