Ceramics midterm

2. Bisque

(bisqueware)- a piece of unglazed clay, pottery or sculpture, that has been bisque fired to Cone 010 - 04

18. Plastic

a characteristic typical of unfired clay when it is moist, soft, pliable, and capable of being formed, manipulated, or easily molded, and still maintains its shape without cracking or sagging.

27. Vessel

a hollowed-out form often used as a container for liquids or dry materials.

17. Oxidation Firing

a kiln atmosphere in which the presence of oxygen is sufficient in quantity to cause combustion of carbon gases. An electric kiln has a normal oxidation atmosphere. Fuel fired kilns can also fire in oxidation providing there is adequate air intake and the atmosphere remains clear.

5. Clay

a plastic material formed by nature over eons and found in the earth, that may be used for making object for functional and sculptural purposes. In its theoretically pure state, it consists of alumina, silica, and water: Al2O3 2SiO2 2H2O. Clays are classified as to type, such as ball clay, fireclay, china clay, etc., based on their compositions, purity, and characteristics.

29. Wedging

a process by hand where clay is mixed, cut & slammed, and "kneaded" to eliminate air pockets, made smoother, denser and homogenous

1. Bat

a round, flat disc used for a base to throw clay using a pottery wheel. May be made of plaster, wood, plywood, Masonite

13. Leather-Hard

a stage in the drying process of clay when it becomes stiff but still flexible, but is still damp enough to be joined to other pieces. The name is akin to the description of shoe leather and clay at this stage may also be carved, incised,

20. Raku

a term in Western terminology taken from Japanese method and altered. A low temperature firing technique usually below cone 06 involving a very rapid firing cycle, removal of ware with tongs from a red-hot kiln, normally post-reducing the ware in a fireproof container with dry organic combustibles for a variable short amount of time, and removal again with tongs and quenching to prevent re-oxidation.

9. Glaze

a thin layer of glass fused to the surface of fired clay. Glaze can be smooth or textured, shiny or dull finished, and may be colored by a variety of oxides/carbonates. The raw unfired glaze never looks like what it will look like fired.

12. Kiln

an insulated fireproof box, usually brick lined oven into which heat is introduced by combustion (fuel fired) or by radiant energy (usually electric) designed for firing ceramic ware. Kilns come in a wide range of shapes and sizes, some permanent and some portable.

8. Earthenware

clay bodies fired at temperatures below cone 1 (2110° F) that remain somewhat porous and open in structure. The vast majority of the world's pottery has been earthenware because of the wide prevalence of earthenware clays and the relative ease of reaching the kiln temperature necessary to mature the claybody. Two examples are terra cotta and whiteware (sometimes referred to as talc body).

23. Slip

clay that is mixed with enough water to be as fluid as cream or as thick as yogurt. Uncolored slip is used to attach together unfired and moist clay pieces to create functional and non-functional art. Colored slip has ceramic coloring oxides added and is used to decorate. Other liquids similar to colored slip are underglaze and engobe. These can be commercially manufactured or made by hand.

28. Vitrification

fired state where clay is hard, dense, non-porous and will hold water w/o glaze

11. Hand Building

forming clay shapes by hand (without a wheel) by pinching, coiling, slabbing, molding, or combinations of these techniques.

21. Sgraffito

in ceramics, a technique where clay is coated with a colored slip which is carved through to expose the clay. Actually, any coating that is scratched through to expose the background.

16. Mishima

is a technique of inlaying slip, underglaze, or even clay into a contrasting clay body, the main clay body of the pottery piece. This technique allows for extremely fine, intricate design work with hard, sharp edges that can be difficult to reliably replicate in any other way.

30. Wheel

referred to as a "potter's" wheel which is a device with a flat circular revolving head mounted on a vertical shaft propelled manually, by hand, or foot (kick), or motorized, usually electric incorporating a variety of drive mechanisms of which there are numerous types, designs, and shapes.

10. Greenware

refers to any state of raw/unfired clay. Including wet, leather-hard and dry/bone dry.

14. Low-fire

refers to clay, usually porous and soft, and glazes that are fired above cone 016 up to cone1. Earthenware & terracotta are examples.

4. Ceramics

the art and science of objects made from earth materials containing or combined with silica with the aid of heat or the process of making these objects.

7. Crazing

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

25. Throwing

the hand forming of hollow shapes out of plastic clay on a revolving pottery wheel head.

15. Maturation

the optimum fired condition/potential or temperature of a fusion of glaze and/or clay when it achieves maximum hardness and non-porosity.

22. Shrinkage

the progressive lessening or contraction of clay in measurable dimensions and volume during both drying and firing. Different types of clay shrink at different rates, usually ranging from 6-14%.

6. Coiling

to construct pottery or sculpture by rolling out clay in thin ropes to build a form

3. Bone Dry

unfired clay which is warm (not cool or damp), dry, and dusty/chalky in feel. Ceramic ware needs to be bone dry prior to bisque firing whereby the physical (free) water has evaporated.

26. Underglaze

usually refers to pigments, applied to raw or bisque clay, that are normally covered with a glaze, such as commercial liquid underglazes like AMACO, chalks/crayons, and pencils. May also describe the technique of application of pigments such as washes.

19. Porcelain

vitreous (glass-like) pale gray to white claybody consisting of primary clay (kaolin/china clay) and fired up to cone 14 or higher and are non-absorbent and have a high-pitched ring when tapped. Porcelains are extremely dense and when very thin, i.e. wall thickness, usually demonstrate a degree of translucency.

24. Stoneware

vitreous gray, buff to brown firing clay bodies above cone 4 to cone 10 (2381° F). The surface is hard, dense, and impermeable -rocklike.