CLAY VOCABULARY

Clay BodyIt is possible to work with the clay as it comes from the earth, however it will not posses certain characteristics such as color, plasticity, strength, or fired density. By mixing two or more clays and adding other materials, these effects can be produced in what is called a clay body.

There are 3 stages:

1.Wet2.Leather Hard

3.Bone Dry

STAGES OF CLAY

GreenwareAny pottery that has not been bisque fired. The clay could be wet, leather hard, or bone dry.

Greenware-all stages of unfired clay

Leather hardClay has begun to dry out and can no longer be formed or molded but the surface can easily be carved

Leatherhard-can ‘t continue to remold but effective carving at this stage

Bone DryClay that has been completely air dried and is ready to go to the first firing (bisque)

Bone Dry-very brittle at this stage, ready for the bisque fire

There are two firings:1.Bisque2.Glaze

Firing the Clay

Bisque FiringThe first firing, without over glaze. However colored under glazes (slips) may be applied to the greenware and then bisque fired.

Bisque firing-load bone dry clay

Glaze Firing

The final firing, with overglaze.

Glazeware: finished glaze firing; ready to be unloaded

PREPARING the CLAY

WedgingKneading the clay in order to expel air and homogenize the clay.

Wedging

ScoringScoring clay is the method potters use to adhere two pieces of clay together. Simply use any pointed clay tool to make X shaped marks into the clay where you will be adhering another piece. This roughs up the surface area of the clay, which is needed for a good adhesion.

Scoring

SlipSlip is another name for clay glue. Slip is simply wet sticky clay. Slip can be applied by a paint brush or simply your finger. Do not use just water.

Slip

BUILDING TECHNIQUES

PINCH

Pinching the clay with your fingers to shape it.

Pinch PotTo make a pinch pot begin with a ball of clay. Push your thumb into the center, and then pinch up the walls. Turn the piece as you pinch. This will help you keep the walls of the piece at an even thickness. Lightly push the bottom of the pot on a flat surface to create a flat spot that it will rest on when finished.

Pinch Pot

Coil PotsCOILS: rope-like strands of clay Layered one upon another to create the

walls of the pot. Smooth coils or leave some coils exposed.

Coil Pot

Coil Pot - Examples

Slab BuildingSLAB: Rolled out flat pieces of clay

Slab Boxes

DECORATIVE TECHNIQUES

SgraffitoSGRAFFITO: This is a decorating technique where a colored slip is applied to a leather-hard piece of clay and left to dry. Once the slip is dry a variety of different tools are used to carve into the clay to remove the slip and leave an embedded decoration behind.

Sgraffito

MishimaA Japanese decorating method of filling a design impressed or carved into the clay with a different colored slip.

Mishima: Comparison Example

Sgraffito on the Left

Mishima on the Right

Crazing The fine network of small cracks that occurs on glazes. The Japanese encourage crazing and will stain cracks with concentrated tea.

Crazing

CLAY TOOLS

Pin/ Needle ToolUsed for trimming while on the wheel and for scoring/cutting clay.

Wire Cutters

Used to cut large pieces of clay

Loop ToolsPerfect for carving and trimming.

Modeling ToolsUsed for shaping and detailing the clay

Ribsshapes and smooths pots as they are being formed