Mid Term
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Agateware - Different colored clays wedged together to create a marbleized effect.
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Albany Slip - Clay body mixed with nontoxic glaze composed of smooth, lustrous brown glaze.
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Alkaline Glaze - a low temperature glaze with an alkaline flux. Alkaline glazes are composed of glass formers and high proportion of lime or soda. Alkaline glazes produce brilliant colors (turquoise or blue) and are typically applied to earthenwares for their low-firing temperature. (associated with Islamic ceramics)
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Ash Glaze - a high-fired stoneware glaze with a flux made from plant or wood ash. Like alkaline glazes, ash glaze contains lime and creates green and blue colors once fired. This glaze matures at a high temperature (1200˚C)
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Baiting - bring about the optimal melting degree by adding coal.
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Ball Clay - Secondary Clay - additive found worldwide to add plasticity to stiff clay. (opposite of Grog)
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Bat - Ball of clay
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Bean pot - Deep, wide bellied vessel with handles, lid for holding large amounts of food/liquid.
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Biscuit Firing - A partly fired or fully fired but unglazed ceramic body. If it has been deliberately left unglazed, the body is usually a fine porcelain. The term can also refer to a stage of firing when a piece is first fired to a relatively high temperature and then glazed and fired again. (The term derives from French, meaning 'twice fired')
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Black, block mould, case mould - A block with a negative of the ceramic body. Pressed onto the outer walls to form the design.
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Blunging - Act of mixing clay and water. Use a machine called the blunger.
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Bone china - A type of porcelain with particularly good translucency owing to the addition of bone ash, which encourages glass formation. The ash is made from cattle bone. Bone china was developed in England by Josiah Spode in the 1790s. It is often referred to as "English porcelain."
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Bungs - vertical stacks of saggers.
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Calcined flint - Raw material clay - mixture of aluminum and silicate with iron and titanium oxides and is used for high-grade refractory ceramic materials.
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Clay - Raw material produced from the breakdown of rocks (granite, quartz, mica, feldspar)
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Clay Body - Clay mixture (different types of clay & additives) used to form ceramics.
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Coggle Wheel - wheel with carved decorative motifs that impress patterns on rims/edges.
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Coiling - hand building a clay vessel with hand rolled clay ropes. Each coil is scored together to form a cohesive body.
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Creamware - Lead glazed earthenware with a cream-colored body. It was developed by Wedgwood in the 1760s as an alternative to porcelain and was renamed Queen's ware after Queen Charlotte ordered a cream ware tea service. It is earthenware and is composed of ball clay, china clay, flint and Cornish stone. Fires at a low temperature and therefore economical to produce. Creamwares were biscuit-fired, then lead-glazed and fired again at a low temperature. They could be left plain or decorated with underglaze painting, overglaze painting, transfer printing, applied decoration and pierced decoration.
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Delftware - Dutch tin-glazed earthenwares with cobalt blue decoration. These imitated Italian Maiolicas. Copied Chinese import porcelain.
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Earthenware - Secondary Clay - "red wares" fires at low temperature (950-1100˚C). Porous and opaque, must be glazed to hold liquid.
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Feldspathic Glaze - A glaze containing a high proportion of feldspar, which is added as a flux. It is used in high fired glazes and can encourage crazing (crackling or faulting in the glaze), owing to its high alkali content.
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Fettling - The trimming of a ceramic after forming and before firing, sometimes also known as 'turning.' This can be done with a sharp tool, usually when the ceramic is on a wheel for turning.
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Filter Press - large canvas bag squeezed to remove excess water from clay body.
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Flux - A substance that lowers the melting-point of a material and aids fusion. Fluxes are used in ceramic glazes and enamels.
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Gilding - Applied by brushing, gold leaf, spraying or banding and afterwards the ceramic is fired for permanence.
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Glost Firing - After the underglaze decoration and overglaze is applied and the body is fired again.
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Green or leather hard, greenware - Leather-hard (adjective) refers to a specific stage during the drying of a pot or other clay object. At this stage, the clay is still visibly damp (usually a darkish gray) but has dried enough to be able to be handled without deformation. The clay is able to be gouged or incised without breaking, but will not receive impressions.
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Grog - A course material consisting of crushed pottery, added to very plastic clay bodies to improve workability. (also known as temper)
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Jigger - Clay is molded on top of a mold (opposite of a jolley)
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Jolley - machine used to press mold a clay body, creating hollowware.
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Kaolin - "China Clay" A white firing clay used to produce porcelain bodies. It is both a primary and secondary clay body. The main chemical makeup is kaolinite. China clay is exceptionally stable and pure and is therefore useful for producing both white bodies and vitreous glazes. It is the essential ingredient for hardpaste porcelain. It can withstand temperatures up to 1700˚C and is therefore used in industrial ceramics as well as fine porcelain vessels. Once fired it is glassy, hard and translucent.
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Kiln:
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Kraak - Chinese blue and white porcelain made for the Dutch market. The name is derived from Dutch ships called Carracks or Caracca.
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Lead Glaze - A low-fired glaze fluxed with lead. It produces a smooth and shiny glaze. It is applied before firing and melts and fuses during firing. Applied as powder or mixed with water and applied directly to the clay body before firing.
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Luting -a tool to score the edges of clay and applying slip as an adhesive.
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Maiolica - Tin-glazed earthenware with polychrome decoration, produced in Italy in the Renaissance period. Emulated Near Easte Wares imported into Majorca, Spain.
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Meissen - the first European hard-paste porcelain that was developed from 1708 by Ehrenfried Walther von Tschirnhaus.
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Milk Pan -Small, shallow, wide vessel for containing milk.
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Muffle Kiln - smaller kiln used for decorated wares. Flues circulate around kiln, a more delicate way of firing.
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Nappy - Mixing Bowl
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Overglaze decoration - A type of enamel taking the form of a lead-based glaze applied over a hard, pre-fired glaze. There are more color options to use for overglaze decoration. This is the advantage, however the colors are not as permanent as underglazed decoration. Overglaze decoration has the "painted on" look.
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Oxidizing versus reducing kiln - Oxidizing kiln allowed for the flow of oxygen whereas the reducing kiln deprives the kiln of oxygen, producing more smoke.
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Petuntse - "china stone" a rock used for the production of porcelain and stoneware. It is formed from the decomposition of feldspar (stone) and is composed of quartz, mica, feldspar and often kaolinite. It has a very small particle size, accounting for the soft clay body of porcelain.
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Pipkin - small earthenware cooking vessel with 3 feet, spoke handle and a lid.
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Porcelain - (Kaolin, Flint, & Feldspare) Kaolin clay is the primary material from which porcelain is made, even though clay minerals might account for only a small proportion of the whole. The composition of porcelain is highly variable, but the clay mineral kaolinite is a significant component. Other materials can include feldspar, ball clay, glass, bone ash, steatite, quartz, petuntse and alabaster. Properties associated with porcelain include low permeability and elasticity; considerable strength, hardness, glassiness, brittleness, whiteness, translucence, and resonance; and a high resistance to chemical attack and thermal shock. Porcelain does not need a glaze for impermeability. Fired at a high temperature (1200˚C +). Nonporous.
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Porringer - Small, shallow dish to hold porridge
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Press molding - Pressing clay into 2 halves of plaster mold. Two halves are joined by making a seam and scoring with slip to make seamless. This method is popular with details (handles, spouts, etc)
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Primary Clays - Residual clay on site of rocky, mountainous regions. Pure white porcelain grains.
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Pudding Pan - Cylindrical Vessel for Indian pudding
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Pug Mill - machine that produces air-free clay and increases clay workability.
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Refractory of fire clay - A very heat-resistant clay, usually associate with coal deposits, which is normally high in alumina and thus high-fired. Because of its very high temperature, it is useful to use in kiln building or in stonewares, which take up to 4 days to fire.
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Ring Jug- Vessel put over the saddle for travel (very durable)
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Saggers - a clay box used to protect delicate or sensitive clays and glazes during firing from smoke, heat and ash. Saggers are stacked in the kiln (often used in oxygen reducing kiln)
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Salt-glaze -The glaze is made by adding salt into the kiln when it reaches max temperature (1000-1100˚C). The salt then splits into chloride vapor and sodium oxide, which is deposited on the surface of the vessel and reacts with the body forming a thin, glassy glaze.
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Secondary Clays - Clay moved by water or glacial movement that has picked up additional minerals (oxides) and small particles. Less pure that primary clay.
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Sgrafitto - A decoration technique often called scratchwork. This technique is used in ancient vessels such as Red-figure Greek vases. Layers are allowed to airdry but no set completely before the design is cut with a knife or tool to peel away the upper layer. Applied during the leather-hard state.
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Slab Construction - individual slabs of clay are scored together and joined with slip.
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Slip Cup - Container for slip decoration that is dispensed through quills (4 in PA Dutch slip cups)
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Slip casting - Pour slip into plaster mold and forms a skin on the inside lining of mold. This speeds the production.
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Slip decoration - slip trailed - Underglaze decoration applied on greenware produced by applying slip or liquid clay mixed with coloring agents, which can be painted on, inlaid, marbled, combed, sprayed on and once dry, cut. The slip need not be the same clay body as the form itself.
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Soft paste porcelain - Artificial porcelain made with white clay (instead of China Clay) and ground glass. Unlike true or hardpaste porcelain, it does not contain kaolin. First made in Europe in the 16th century, known as "Medici porcelain" and was replaced by true porcelain in the 18th century.
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Spittoon - receptacle for spitting into, especially when chewing tabacco. It typically has a wide rim (mouth) and funnel function.
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Sprigging - a type of mold used to produce decoration in relief (think Wedgwood) with a flat back that can be scored and slipped for application.
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Stoneware - A hard, high-fired ceramic body which, because of its high firing temperature (above 1200˚C) is dense and relatively non-porous. Colors range from white to gray. Most stonewares are glazed with ash or salt glazes or left unglazed. Once fired, stoneware is very durable.
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Tin-lead Glaze - A white glaze opacified with tin. White tin glazes were first used in the Near East. They are normally associated with Near East or Chinese wares. A traditional tin glaze is simply a lead glaze that has been opacified with tin. They produce a white glaze that disguises unsatisfactory body material. Their whiteness is ideal for painted decoration as seen on luster wares.
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Transfer printing - a process of decorating ceramics with a printed design transferred from a thin sheet of gelatin or tissue paper. Initially used on porcelain and later used on earthenware around 1800. An engraved copper plate is heated and prepared with ink and then transferred onto sheet then rubbed onto biscuit-fired ceramic. Beneficial for industrial production.
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Underglaze decoration - decoration applied to a ceramic body under a transparent glaze. Permanent decoration and can be painted on or printed (transfer-printed). Normally executed with cobalt, iron and copper oxides)
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Wedging - the act of kneading clay to remove air pockets to prevent the clay from exploding in the kiln.
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Wheel throwing - 16th century kickwheel. Ball of clay is centered on wheel (now automatic) and built up using hands.
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White salt-glazed stoneware - salt-glazed, grey to white bodied non porous stoneware with an orange peel texture. Used for many vessel forms.
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Wood Ash Glaze - typically creates a 'dripped look' on stoneware.
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continuous/tunnel - objects are loaded on a conveyor belt and travel through kiln, today this is done electrically.
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intermittent/bottle - central enclosed kiln with objects loaded inside and temperature is controlled.
