Glossary of Ceramic Terms

For the purpose of general reference, the scope of these glossaries extends beyond terms used in the textbook. Other Glossaries: Ceramic Fiber Glass Metal Wood

Scroll down or select a first letter range: <a-f> <g-m> <n-s> <t-z>

View Glossary Credits

Agate ware: a variegated earthenware made of different colored clays; it was frequently used by Thomas Whieldon in Staffordshire in the eighteenth century Return to Top
Alumina: one of three necessary ingredients in a glaze, which gives the glaze a viscosity Return to Top
Anagama: a Japanese single chambered cross-draft kiln with a firebox at one end and a chimney at the other, which draws the heat and flames through the chamber. They often are fired for days at a time, and have side-stoking holes to help maintain evenness of temperature. Return to Top
Ash Glaze: glazes from the alkaline glaze family that ultimatly occur due to firing objects in a wood-fired kiln. Dates back to the Bronze Age in China. Return to Top
Atomizer: a sprayer used to distribute a fine mist of glaze onto the surface of a ceramic object Return to Top
Basaltes ware: unglazed black stoneware perfected by Josiah Wedgewood in Staffordshire in the eighteenth century Return to Top
Beehive kiln: named for its shape, a kiln with a firebox that fires from underneath, and a flue on the top to control oxidation within the kiln Return to Top
Bisque: preliminary firing to harden the ware for glazing Return to Top
Black figure: a technique used by ancient Greek potters whereby figures were drawn in black on a reddish clay ground Return to Top
Body: is the mixture of clay and other ingredients out of which pottery is made Return to Top
Burnishing: dry polishing of a hardened unfired piece to produce a glaze-like surface which may be fired Return to Top
Casting: a method of reproducing in quantity by using liquid clay and molds Return to Top
Celadon Glazes: the European and name given to Chinese stoneware glazed in a gray-green semi-opaque to opaque glaze (reduction fired) derived from iron oxide Return to Top
Centrifugal force: a force that pushes the momentum of circular movement to the outside of the circle Return to Top
China Paint(ing): a low fire glaze decoration applied to already glazed and fired whiteware or porcelain Return to Top
Chinoiseries: fanciful European interpretations of motifs, patterns and compositions believed to be characteristic of Chinese ornament; at times during the seventeenth and eighteenth centuries, it was fashionable in all of the decorative arts Return to Top
Clay Body: a composition of various ceramic materials Return to Top
Coil building: a clay forming technique in which the artist coils rolled clay into a vessel shape by stacking and smoothing the clay coils Return to Top
Cone: thin, finger-length pyramid of ceramic material made to bend and melt at prescribed temperatures, providing a visual indication of temperature in the kiln Return to Top
Crackle glaze: a glaze with minute, decorative surface cracks, sometimes accented by rubbing with color; highly developed in china, this technique has been used widely by nineteenth and twentieth-century Western potters Return to Top
Crawling: a defect in the glaze surface caused by tiny cracks during the drying process, which forces the glaze to crawl into separate areas, leaving exposed portions of the clay in between. Return to Top
Crazing: the formation of a mesh of fine cracks over the surface of a glaze Return to Top
Creamware: a lead-glazed earthenware the color of heavy cream; a creamware developed by Josiah Wedgewood in Staffordshire in the eighteenth century was known as “Queen’s Ware” Return to Top
Crystal(line) glazes: glazes featuring clusters of crystal-like shapes or colors within a more uniform, opaque glaze Return to Top
Delftware: tin-glazed earthenware produced in the Netherlands and taking its name from the town of Delft where it was made on a large scale in the seventeenth and eighteenth centuries Return to Top
delftware: tin-glazed pottery produced in England, sometimes resembling that produced in the Netherlands Return to Top
Earthenware: natural, porous clay which fires to a reddish brown Return to Top
Enamels: a finely ground vitreous substance, often containing brilliant color, used for overglaze painting of pottery; enamels fuse onto the surface of the fired glaze at a relatively low temperature Return to Top
Engobe: White or colored slip applied to a fired or unfired clay body. Typically is more vitreous than the clay body, but not as glassy as a glaze. Return to Top
Extruder: a piece of equipment used to create a uniformly shaped tube of clay by forcing the clay through a die. Often used for creating handles, coils and other uniform components in clay construction. Return to Top
Faience: the term used by the French for tin-glazed earthenware from the sixteenth century onward; it is derived from Faenza, a major Italian center for this type of ware in the fifteenth century Return to Top
Flambé glaze: a glaze derived from copper which turns a rich red mottled with blue when fired in reducing kiln atmosphere Return to Top
Flameware: A flameproof ware, as distinct from ovenware Return to Top
Flux: one of three necessary ingredients in a glaze, which serves as a melting agent Return to Top
Glazes: glassy coating painted onto clay bodies that seal, protect, and decorate Return to Top
Grogged: Crushed hard-fired clay, used in terra cotta and refractory clay bodies to reduce shrinkage. Gives the clay body a rougher texture. Return to Top
Groundhog kiln: Like an anagama kiln, except mor rectangular, and without the side-stoking holes. Usually fired no more than a day's duration. Return to Top
Hausmaler: an independent decorator who painted pottery in his home or outside the factory Return to Top
High fire glazes: glazes that require extremely hot firing conditions Return to Top
Incised motifs: designs cut into unbaked clay, or through a layer of slip or glaze, with a sharp instrument Return to Top
Inlay: a technique of decoration in which the object is incised with a design, colored clay is pressed into the incisions, and the piece is then scraped to confine the colored inlay to the incisions. Return to Top
Isoriato wares: pottery decorated with scenes from stories, primarily biblical and mythological; they were particularly characteristic of Italian maiolica of the sixteenth century Return to Top
Jasperware: fine stoneware that may be colored all the way through its body by the introduction of metallic oxides; colors range from pale blue to green, lilac, yellow, maroon, and black Return to Top
Kaolin: pure clay Return to Top
Kiln: a furnace used for “cooking” clay Return to Top
Low fire: clay fired at a temperature sufficient to fuse it into a solid mass, but too low to make it completely non-absorbent Return to Top
Low fire alkaline glazes: glazes that produce brilliant colors when combined with other chemicals Return to Top
Low fire lead glazes: less frequently used lead-based glazes that fire around Cone 4 to a yellow tint (dangerous in the “raw” state and for glazing kitchen objects) Return to Top
Luster: a metallic or iridescent effect resulting from the application of a thin film of metallic oxide Return to Top
Luting: using slip to attach pieces of unfired pottery together, such as relief decoration, handles, and other elements Return to Top
Maiolica/Majolica: the generic term for the tin-glazed earthenware made in Italy, derived from Majorca, from where much tin-glazed pottery was exported to Italy Return to Top
Matte glaze: a non-gloss or dull surface glaze Return to Top
Mold: a negative model of an object, into which clay (or glass or metal) can be poured to assume its shape Return to Top
Nichrome wire: a heat-resistant nickel/chromium alloy used to support large forms in wet clay in the kiln until they harden during the firing process Return to Top
Overglaze painting: decoration applied to pottery after it has been glazed and fired; enamels were frequently used for this type of decoration, particularly those whose colors were compatible with the lower temperatures of the secondary firing necessary to fix them to the surface. Return to Top
Oxidation: a firing process in which the kiln is burning fuel at its maximum capacity, resulting in brilliant glazes Return to Top
Oxide: a wash derived from various metals applied to clay bodies prior to firing to change their color Return to Top
Pearlware: a creamware with a bluish glaze developed by Josiah Wedgewood in Staffordshire in the eighteenth century Return to Top
Pinch: a clay forming technique in which the artist’s hands pinch the clay into shape Return to Top
Porcelain: a hard, translucent white clay, which is fired at extremely high temperatures Return to Top
Porcellaneous: ceramic bodies that have some of the attributes of porcelain; the term is usually applied to certain types of highly vitrified stoneware Return to Top
Pyrometric cones: a series of cones which indicate the temperature of the kiln by their melting points Return to Top
Raku: a Japanese-developed firing technique which involves firing glazed clay briefly, exposing the clay to organic materials which oxidize on the clay surface, and then cooling and sealing the “glaze” by immersing the object in cold water Return to Top
Ram pressed: clay pressed into a mold by a machine allowing multiple reproduction of the same design Return to Top
Red figure painting: a technique used by ancient Greek potters whereby a black ground was laid on a red clay, silhouetting figures left in the color o the ground Return to Top
Red ware: a generally utilitarian form of American pottery made of common brick clay Return to Top
Reduction: a firing process in which organic matter is introduced into the kiln producing a higher level of carbon in the kiln, which results in more subtle glazes Return to Top
Reserve: a section on pottery kept free of background color and reserved for decoration Return to Top
Revelation kiln: a high-heat kerosene-driven kiln created by Mary Stratton and Horace Caulkins in the late 19th century Return to Top
Saggar: a clay box in which pottery is fired to protect the ware from flame and ash Return to Top
Salt glaze: a pebbly, “orange-peel” glaze achieved by throwing salt into a hot kiln Return to Top
Sang de boeuf: a copper-red glaze, Chinese in origin, copied by potters everywhere Return to Top
Sawdust-fired: a primitive firing technique in which slow-burning sawdust produces subtle gradations of color Return to Top
Scroddled ware: the term for nineteenth century American pottery made of striated clays of different colors, similar to English agate ware Return to Top
Sgraffito: decoration incised on a pot after it has been dipped in slip or glaze Return to Top
Silica: one of three necessary ingredients in a glaze, which gives the glaze its glassy appearance Return to Top
Slab-building: a clay forming technique in which flat slabs of clay are built into shape or vessels Return to Top
Slip: liquid clay used in the manufacture and decoration of pottery; also used for luting together pieces of pottery Return to Top
Slip casting: producing objects using plaster molds and liquid clay (slip); this method allows for multiple reproduction of the same design Return to Top
Slip glazes: watery clay used for decorative effects and applied by pouring, dipping, brushing, and spraying Return to Top
Slip Trail: the process of applying slip to the surface of a ceramic object by trailing a line of color from a bulb/syringe Return to Top
Sponged ware: pottery decorated by applying colors with sponges or soft rags; many pieces were made in Staffordshire in the nineteenth century for the American market Return to Top
Sprigging: molded decoration applied as relief ornament to pottery Return to Top
Stoneware: a natural clay, which can hold water with being glazed, and fires to a gray-brown Return to Top
Terra Cotta: hard, unglazed, brown-red earthenware clay, most often used for ceramic sculpture, including small figures and architectural ornaments Return to Top
Three-color glazes: a form of decoration frequently seen on pottery of the T’ang dynasty, consisting of shades of yellow, green, and blue Return to Top
Throwing off the hump: the process of wheel-throwing individual vessels off of the same piece of clay Return to Top
Tin-glaze: an opaque white glaze resulting from the addition of tin oxide to a siliceous lead glaze; Maiolica, faience, and delft are all tin-glazed wares Return to Top
Tortoise shell: an earthenware with mottled appearance created by the use of differently colored lead glazes; it is sometimes called Whieldon after Thomas Whieldon who perfected it in the eighteenth century Return to Top
Trailing: the process of making a design on earthenware by dripping liquid slip onto a piece of pottery Return to Top
Transfer-printed decoration: a process whereby a design from a specially inked copper engraving is transferred to the surface of glazed pottery through the use of a thin paper transfer Return to Top
Treadle wheel: a wheel powered by a foot pedal Return to Top
Underglaze: pigments applied to the raw clay or bisque and covered with a transparent glaze, having the advantage of permanence Return to Top
Vitreous: Glassy, often in reference to the quality of a glaze. Or a state of firing when the clay body almost mimics the properties of molten glass, and ultimately chemically changes to make a clay body watertight instead of porous (vitirification). Usually refers to either stoneware or porcelain clay bodies. Return to Top
Vitrification: the process in which certain clay bodies, under great heat, undergo chemical changes that make them extremely hard, and impervious to liquids, even without a glaze Return to Top
Wax resist: decoration by applying liquid wax to pottery or a layer of glaze so that a successive layer of glaze will not adhere to the wax-decorated area Return to Top
Wheel-throwing: a clay forming technique in which a potter “throws” clay into symmetrical vessels by using the centrifugal force of a spinning wheel to “pull” the form up from a mound of clay Return to Top
Whiteware: generic term for white clay bodies usually high in kaolin Return to Top
Yellow-ware: a nineteenth-century American pottery created by firing the common clay that is used to make redware at a higher temperature, thus producing a stringer, paler ware Return to Top