A-B
Antefix
Ornament which terminates the covering tiles of the roof and conceals the joints between tiles
Appliqué
Piece of moulded clay stuck onto a ceramic vessel to form ornamental motifs
Assemblage
A collection of things made by grouping found objects |
Baluster
A tall pot or jar with a constricted neck
Biscuit
Another term for bisque, designating fired unglazed pottery |
Burnished
Highly polished
C
Calcining
To reduce, oxidise, or remove all moisture with strong heat
Carinate
Having a keel-like ridge. In ceramology, it refers to a shape where the joints of a vessel’s body meet sharply to form a ridge
Cavetto
The concave area of the face of a ceramic vessel |
Celadon
Pottery made with a translucent green glaze, often with a grey or a blue tint, and less frequently with a yellow hue
Ceramic
A manufactured article made from combining clay and water into a soft, malleable paste which can then be formed into any shape desired and is finally hardened by heat |
Ceramology
The study of ceramics
Clay
Clay is a soft, loose, earthy material containing particles with a grain size of less than 4 micrometres (μm). It forms as a result of the weathering and erosion of rocks containing the mineral group feldspar (known as the ‘mother of clay’) over vast spans of time.
Cobalt
A chemical element with the atomic number 27 and symbol Co. The pigment produced from it gives a distinctive blue tint and has been used since ancient times on jewellery, glass and pottery. In Asia, it first made its appearance during the Tang Dynasty (618-906) on the famous Tang sancai ware. The Chinese made these with cobalt imported from the Middle East until the early 15th century, when local supplies were discovered as near as Yunnan in southern China. (Brown 1988: 76)
Coiling
A technique where a piece of ceramic ware is made by coiling a long strip of clay onto a flat base then fashioned upwards by pinching and beating the clay into a desired shape
Cord-cut
When a length of cord is used to remove a piece of formed clay from the base on which it was made
Crazed
Having a network of fine cracks on the surface of a fired ceramic
Cross-draft
A fuel-burning kiln, usually down-draft, where heat enters at floor level at one side of the ware chamber and exits at floor level at the opposite side of chamber. The primary draft or airflow through the kiln is from side to side. The burner, or firebox, is on one side. The flue (a duct for smoke and gases) is on the opposite end of the kiln. This is unlike downdraft kilns where the flue is in the centre. |
D-E
Downdraft
Downdraft (adjective) refers to the circulation of the air inside a kiln while it is firing. In a downdraft kiln, the air moves from a firebox at the base of the kiln upward into area where the ceramics are stacked (stack area), then swirls back downward to exhaust through a chimney opening at the base of the kiln. Downdraft kilns are designed to force the flame and heated air to circulate through the kiln. The flame is introduced at the bottom of the kiln and naturally flows upward. The construction forces the flame back downward, to exhaust at the bottom of the kiln. Downdraft (noun) is also often used by potters as a shortened form of ‘downdraft kiln’. |
Earthenware
Pottery made of clay fired to a porous state. It can then be made impervious by the use of glaze. Usually refers to ceramic vessels and containers whereas ‘terracotta’ can be applied to figurines and other types of ceramic art.
Enamel
An opaque or semi-transparent glassy substance applied to hard surfaces as ornamentation or as a protective coating. Usually applied to an already fired glaze then re-fired at a lower temperature.
F-G
Faience
Glazed ceramic ware, in particular decorated tin-glazed earthenware of the type that includes Delftware and Maiolica (also Majolica)
Feldspar
An abundant rock-forming mineral typically occurring as colorless or pale-colored crystals and consisting of aluminosilicates of potassium, sodium, and calcium
Fire
(noun) The process of using heat to desiccate and to harden a vessel made of clay in a kiln
(adjective) The state of a clay-made vessel prior to or after firing.
Flange
A projecting flat rim, collar, or rib on an object serving to strengthen or to maintain position
Foot
The base of a ceramic form
Frit
A component of glazes consisting of finely ground raw material (sand or quartz, lead and other oxides). When mixed and placed in an unglazed earthen pot and heated in a kiln for several hours, the mass melts into a clear glass. The molten glass is then poured into a pit filled with cold water. The quenching solidifies the molten glass into granules and thus frit is obtained. The tradition of making frit in a pottery kiln to be used for glazing is an ancient one.
Furniture
Supports made of baked clay used for the stacking of ceramic wares in kilns. Usually consist of tubular supports (or pontils) or round clay disks with three or five raised knobs or spurs. These supports tend to leave very distinct marks called scars on the finished product. |
Glaze
A liquid, glass-like substance applied onto the surface of a ceramic and made to fuse to the surface with heat. The purpose of glaze is to form a hard, impervious, decorative coating making the ceramic ware waterproof.
H-I-J
Heap and Pile
Speckles (spots) occurring in an underglaze whose mineral has not been ground finely enough so that it burns unevenly during firing. Considered a defect.
In-ground
A kiln that is partly buried in the ground, while the top half is made of various materials depending on the region. (At Sankampaeng, Northern Thailand, for example, the in-ground kiln is made of hardened earth and mixed with broken bricks.) |
Inlay
A decorative technique of inserting contrasting, often different coloured, materials into depressions of an object to form patterns or pictures that are flush with the surface of the object.
K-L
Kaolin
A fine, soft white clay, resulting from the natural decomposition of other clays or feldspar |
Kendi
A globular vessel with a spout and a long neck used for holding water. The word is Indonesian, derived from the Sanskrit kundika, which specifically designates an ascetic’s water pot. See a short article on the history of kendis here.
Kiln
A furnace or oven for burning, baking, or drying, especially one for calcining lime or firing pottery
Lie-de-vin
A type of glaze colour coined by the French archaeologist Bernard P. Groslier, which resembles the colour of the residue left in old wine bottles. It is characteristic of a part of Khmer production of the 10th-11th centuries.
Lime pot
A container holding powdered limestone; used in South and Southeast Asia as an ingredient in the local tradition of chewing betel
M-N-O
Mammiform
An adjective describing an object that represents a female mammary/breast
Monochrome
A single-coloured glaze used for decorative purposes on a piece of ceramic |
Overglaze
A method of decorating ceeramics, when a second glaze is applied over or on top off an already glazed ceramic ware; overglazes are usually fired at a lower temperature than the initial firing (as in the case of coloured enamels)
Oxidizing kiln atmosphere
When there is a sufficient or excessive supply of oxygen in a kiln during the firing process, as opposed to a reducing kiln atmosphere when there is an insufficient supply of oxygen
P-Q-R
Polychrome
Refers to a ceramic piece that has multi-coloured decoration, usually made with different coloured glazes
Pontil
Kiln furniture, in this case a tubular support for ceramics when they are sticked in a kiln
Porcelain
A white, vitrified translucent ceramic made from porcelain stone mined from the mountains then ground into powder |
Pottery
Articles made of baked clay; broadly divided into earthenware, stoneware, and porcelain; another term for ceramics
Reducing kiln atmosphere
When there is an insufficient supply of oxygen in a kiln during the firing process, as opposed to an oxidizing kiln atmosphere when there is a sufficient or excessive supply of oxygen; also referred to as a ‘reduction’ atmosphere
Rouletting
A process using a carved stamp to impress repeated and continuous designs onto an unfired ceramic piece |
S-T
Sagger
A large unglazed ceramic box or container that holds one or more ceramic pieces when they are being fired inside a kiln |
Sherd
Shortened form of ‘potsherd’, a broken piece of ceramic material, especially one found on an archaeological site
Sintering
The process of making a powdered material coalesce into a solid mass by heating it without liquefaction
Slip
A creamy mixture of clay, water, and sometimes a pigment, used especially for decorating earthenware, often used to provide a lighter background covering over a darker clay body |
Spur disc
A pre-fired ceramic piece in the shape of a disc with three or more spurs that allows unfired ceramics to be stacked on top of one another in a kiln, thereby saving space and preventing the ceramics from fusing together during the firing |
Stacking ring
A ring made of clay, already previously fired, that allows ceramics to be stacked upon each other in a kiln to save space. (See ‘spur disc’)
Stoneware
A type of ceramic that is made to be as hard as stone and is much less porous than low-fired earthenware
Terracotta
From Italian ‘baked earth’: unglazed low-fired red earthenware clay objects.
In archaeology and art history, ‘terracotta’ is often used of objects not made on a potter’s wheel, such as figurines, whereas objects made on the wheel from the same material, possibly even by the same person, are referred to as ‘pottery’.
U-V-W-X-Y-Z
Underglaze
Decoration on pottery done before glaze is applied
Updraft
Updraft (adjective) refers to the air flow through a kiln as it is firing. In an updraft kiln, the air flows from a firebox at the base of the kiln and exhausts out the top of the kiln.
Updraft (noun) is used by many potters as a shortened form of saying ‘updraft kiln’.
Updraft kilns are those in which the flame is introduced into the bottom of the kiln, at or below floor level, and exhausted out the top. Updraft kilns consist of three basic components: the firebox, the damper, and the stack area. The firebox is where the flame enters. The damper is at the top of the kiln and controls the exhaust (and by association, the kiln’s atmosphere). The stack area is where the pots are set and is between the firebox and damper.
An updraft kiln tends to be less fuel efficient than a downdraft kiln.
Vitrify
To change into glass or a glass-like substance by heat |
Waster
A discarded piece of defective pottery
Wheel
Short for ‘pottery wheel’, a device that turns a flat surface (either by an electric motor or manually kicking a tread or pulling a lever) onto which a lump of clay is placed by a potter, to be centred as the wheel turns, then manipulated by the hands and tools of the potter to transform it into a vessel
Zoomorphic
An adjective used to describe a shape either having the shape of, or representing, an animal form