Ceramics 1
Jason Kishell
Ceramic Vocabulary
Earthen material- Any substance or compound that is extracted from the earth
Clay- A dense earthen material comprised of fine-particle rock and water; Types of clay: Ball Clay, Kaolin, and Fire Clay
Primary Clay- Closest to the mother rock
Secondary Clay- Found far from the mother rock and mixed with impurities
Clay Body- A specific formula of earthen materials that are combined with water to create a dense mud-like substance
(primarily consisting of alumina and silica); clay, flux, and glass-maker
Earthenware- low mature point, usually dark in color or high in talc, smallest particle size
Stoneware- high mature point, contains iron and other impurities
Porcelain- highest maturing point, purest clay body, always white, largest particle size, translucent at maturity
Porcelainous- acts like a porcelain but does not follow the “true” definition
China- clay mixed with bone ash, white in color, resembles porcelain
Plasticity- A clay body’s ability to stretch and move without breaking
Short- The term used to describe clay that is low in plasticity
Slip- A saturated clay body, usually 50% or more water to clay ratio
Score and Slip- The method for attaching or “gluing” two pieces of clay together
Ceramic- Clay that has been permanently hardened by a chemical reaction caused by heat
Greenware- any stage of clay work before it is fired
Wet- clay contains enough moisture to be pliable
Leather hard- clay is hard, but not dry, moisture is still present in clay’s composition, ideal stage for carving
Bone dry- clay is completely dry and brittle
Wedging - Rolling and compressing clay in a manner that pushes out excess air and aligns clay particles
Cone- Temperature rating for ceramic material
Refractory – n. A heat-resistant agent; adj. Resistant to heat and melting
Flux- n. A melting agent; v. To melt or to promote melting; to make vulnerable to heat
Mature (maturity) – The point (a specific temperature that is different for each clay or clay body) at which a clay body is
compressed, through heat, making it vitreous and hardened
Firing- a method of heating up ceramic material to a desired temperature
Kiln- any container used to fire ceramic material
Bisque- 1st firing of clay, expunges volatile chemicals and transforms clay through the “ceramic change” or quartz conversion,
making it hard and solid ceramic; Bisqueware- Stage between bisque firing and final firing
Handbuilding- Any work in clay made from using hand construction techniques (slab, coil, pinch)
Pinch method- Working with clay using a series of “pinches” to create a form
Coil building- Working with clay using rolled coils that are scored and slipped together to create form
Slab construction- Working with clay using thrown or rolled slabs to create a form
Glaze- A glass-like earthen material that is fired onto clay; clay, glass-maker, flux, and colorant
Underglaze- A colored earthen material fired onto the surface of clay (usually on bisqueware)