Ceramic Terms Flashcards
Bat
A flat disc made out of plaster, wood, or plastic which is affixed to the wheel head with clay or pins. Bats are used to throw pieces on that would be difficult to lift off the wheel head.
Batch
- A mixture of weighed materials such as a batch of glaze or slip or a clay body.
Banding Wheel
A revolving wheel head which sits on a pedestal base. It is turned by hand and used for finishing or decorating pottery
Bisque
Pottery which has been fired once, without glaze, to a temperature just before vitrification.
Bisque Fire
First firing, without glaze. Slips can be used in a bisque firing.
Bone Dry
Completely air dried.
Burnishing
The ancient rubbing process of burnishing polishes the outside skin of a clay pot while greatly reducing its porosity. This finishing is done by hand, using a stone or a metal piece which is usually embedded in a wad of wet clay that perfectly fits the burnisher’s hand
Calipers
A tool used to measure the diameter of round forms, for example calipers are used to get lids to fit just right.
Centering
Technique to move the clay in to a symmetrical rotating axis in the middle of a wheel head so you can throw it.
Ceramics
objects made from clay that permanently retains their shape after being heated to specific temperatures.
Chuck
A piece used to aid the potter in trimming. A chuck is a form that can hold a pot upside-down above the wheel head while the potter trims it. Chucks are thrown and bisque-fired clay cylinders which are open on both sides
Clay
A MOIST EARTH OF DECOMPOSED ROCK; USED IN PRODUCTS SUCH AS POTTERY, BRICKS, TILES, AND SCULPTURE.
Alumina + silica + water = Al₂O₃ + 2SiO₂ + 2H₂O
Clay body
A mixture of different types of clays and minerals for a specific ceramic purpose. For example, Porcelain is a translucent white clay body
Coil
A piece of clay rolled like a rope, used in making pottery.
Compress
Pushing the clay down and together, forcing the particles of clay closer.
Composite Pots
Pots that were thrown, or hand built in separate pieces and then assembled.
Pyrometric Cone
A pyramid composed of clay and glaze, made to melt and bend at specific temperatures. It is used in a kiln to determine the end of a firing or in some electric kilns it shuts off a kiln setter.
Crazing
The cracking of a glaze on a fired pot. It is the result of the glaze shrinking more than the clay body in cooling process.
Crawling
A bare spot (from the shrinking of a glaze) on a finished piece where oil or grease prevents the glaze from adhering to pottery.
Damper
A slab of refractory clay that is used to close or partially close the flue of a kiln.
Dry-Foot
To keep the foot or bottom of a pot free from glaze by waxing or removing the glaze.
Earthenware
A low fired clay body. Glazed pottery is fired to a temperature of 1,830 - 2,010 degrees Fahrenheit. Available in red or also white.
Englobe
Colored clay slip used to decorate Greenware or leather hard pieces before bisque firing. Clay and oxide and water.
Extrusion
Clay forced through a die to form uniform shaped
Fettling Knives
These tools are useful in cutting large lumps of clay, cleaning edges of cast pieces, and in removing thrown work from the potter’s wheel.
Fire
To heat a clay object in a kiln to a specific temperature.
Firebrick
An insulation brick used to hold the heat in the kiln and withstand high temperatures
Firing Range
The range of temperature at which a clay becomes mature, or a glaze melts.
Flux
A melting agent causing silica to change into a glaze.
Foot
Base of a ceramic form.
Frit
A glaze material which is derived from flux and silica which are melted together and reground into a fine powder.
Glaze
- A thin coating of glass. An impervious silicate coating, which is developed in clay ware by the fusion under heat of inorganic materials.
Glaze firing
The final firing, with glaze.
Gloss Glaze
- A shiny reflective gloss.
Greenware
Unfired pottery. Ready to be bisque fired.
Grog
Fired clay ground to various mesh sizes.
Kiln
A furnace of refractory clay bricks for firing pottery and for fusing glass.
Kiln Furniture
Refractory posts and shelves used for stacking pottery in the kiln for firing.
Kiln Wash
Mixture of Kaolin, flint and water. It is painted on one side of the kiln shelves to separate any glaze drips from the shelf.
Leather Hard
Stage of the clay between plastic and bone dry. Clay is still damp enough to join it to other pieces using slip. For example, this is the stage handles are applied to mugs.
Loop Tools
Tools with ribbons of wire for shaping and trimming ceramic objects.
Majolica
A low fire glazing technique. The process involves applying an opaque tin glaze to earthenware and painting it with different colored oxides.
Matt Glaze
A dull glaze surface, not very reflective when fired. It needs a slow cooling period or it may turn shiny.
Mold
A plaster shape designed to pour slip cast into and let dry so the shape comes out as an exact replica of the mold.
Maturing Point
The temperature at which the clay becomes hard and durable.
Needle Tool
These long heavy needles set into wooden, metal, or plastic handles are one of the most versatile tools in pottery.
Opaque Glaze
Non-transparent glaze, it covers the clay or glaze below it.
Oxidation
Firing with a full supply of oxygen. Electric kilns fire in oxidation. Oxides show bright colors.
Peephole
A small observation hole in the wall or door of a kiln
Pinch
Manipulate clay with your fingers in your palm to a hollow shape. Pinch pots are a popular beginners project.
Plasticity
The quality of clay which allows it to be manipulated into different shapes without cracking or breaking.
Porcelain
White stoneware, made from clay prepared from feldspar, China clay, flint and whiting.
Potter’s Wheel
A device with either a manual (foot powered) or an electric rotating wheel head used to sit at and make pottery forms
Pug
To mix.
Pug Mill
A machine for mixing clay and recycling clay.
Raku
This process is an economical way of firing ware in reduction to achieve metallic and carbon effects. Normally ware is heated in a kiln until the glaze is melted to the desired degree then it is removed with tongs and put into a container of organic or combustible material (i.e. sawdust, paper, straw) where it is cooled. Raku ware is usually crazed and very porous and lacking in strength. Thus it is only suitable for decorative ware.
Reduction
Firing with reduced oxygen in the kiln.
Rib
A rubber, metal or wooden tool used to facilitate wheel throwing of pottery forms.
Satin Glaze
A glaze with medium reflectance, between matt and gloss.
Scoring
edges (or surface area) of clay before joining them together with slip
Sgraffito
Scratching design on pottery.
Slab
Pressed or rolled flat sections of clay used in hand building.
Slip
]Clay mixed with water with a mayonnaise consistency. Used in casting and decoration.
Slurry
A thick slip.
Soaking
Maintaining a low steady heat in the early stages of firing to achieve a uniform temperature throughout the kiln
Stacking
Load a kiln to hold the maximum number of pieces.
Stain -
Oxide and water, used as a colorant for bisque wear
Stoneware
All ceramic wear fired between 2,100 and 2,300 degrees.
Transparent Glaze -
- Transmits light clearly.
Terra cotta - ‘Terra Cotta’ (Italian for ‘cooked earth’) is red burning earthenware, generally unglazed. Terracotta is normally used to make sculptures, tile, planters, garden and architectural ware.
’ (Italian for ‘cooked earth’) is red burning earthenware, generally unglazed. Terracotta is normally used to make sculptures, tile, planters, garden and architectural ware.
Throwing
- Creating ceramic shapes on the potter’s wheel.
Vitrification -
Vitrification
Wedging
A method of kneading clay to make it homogenous by cutting and rolling.
