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87-488: The Burghley Nef is a parcel-gilt salt cellar made in Paris in 1527–28 (or possibly earlier). It is in the form of a late medieval ship, the hull made from a nautilus shell . The ship sits on the back of a mermaid on an hexagonal base. The height is 34.8 centimetres (13.7 in). In medieval France the word nef was applied to various types of boat-shaped containers, including the most magnificent objects intended for

174-408: A camel ) arranged in a single or double row along a flat ferrule made of wood or cardboard. In order to transfer the gold leaf, the hairs are first given a very light coating of adhesive by brushing them against a surface such as the back of the user's hand which has been coated with a thin layer of petroleum jelly (a common misconception is that static electricity causes the gold foil to attach to

261-512: A kiln to permanently set their shapes, vitrify the body and the glaze. Porcelain is fired at a higher temperature than earthenware so that the body can vitrify and become non-porous. Many types of porcelain in the past have been fired twice or even three times, to allow decoration using less robust pigments in overglaze enamel . Porcelain was invented in China over a centuries-long development period beginning with "proto-porcelain" wares dating from

348-547: A patent on a porcelain containing bone ash. This was the first bone china , subsequently perfected by Josiah Spode . William Cookworthy discovered deposits of kaolin in Cornwall , and his factory at Plymouth , established in 1768, used kaolin and china stone to make hard-paste porcelain with a body composition similar to that of the Chinese porcelains of the early 18th century. But the great success of English ceramics in

435-403: A major European factories producing tableware, and later porcelain figurines. Eventually other factories opened: Gardner porcelain, Dulyovo (1832), Kuznetsovsky porcelain, Popovsky porcelain, and Gzhel . During the twentieth century, under Soviet governments, ceramics continued to be a popular artform, supported by the state, with an increasingly propagandist role. One artist, who worked at

522-430: A mark of their status. At the foot of the main mast, engaged in a game of chess, are the tiny figures of the lovers Tristan and Iseult who, according to the legend, mistakenly drank a love potion and suffered tragic consequences. The nef was discovered by Arthur Grimwade in the basement at Burghley House in 1956, and sold on 17 July 1959 when the 6th Marquess of Exeter auctioned part of his silver collection. It

609-514: A paste composed of kaolin and alabaster and fired at temperatures up to 1,400 °C (2,552 °F) in a wood-fired kiln, producing a porcelain of great hardness, translucency, and strength. Later, the composition of the Meissen hard paste was changed, and the alabaster was replaced by feldspar and quartz , allowing the pieces to be fired at lower temperatures. Kaolinite, feldspar, and quartz (or other forms of silica ) continue to constitute

696-631: A publication now in the public domain :  Chisholm, Hugh , ed. (1911). " Gilding ". Encyclopædia Britannica . Vol. 12 (11th ed.). Cambridge University Press. pp. 13–14. Porcelain Porcelain ( / ˈ p ɔːr s ( ə ) l ɪ n / ) is a ceramic material made by heating raw materials , generally including kaolinite , in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). The greater strength and translucence of porcelain, relative to other types of pottery , arise mainly from vitrification and

783-561: A source of imperial pride. The Yongle emperor erected a white porcelain brick-faced pagoda at Nanjing , and an exceptionally smoothly glazed type of white porcelain is peculiar to his reign. Jingdezhen porcelain's fame came to a peak during the Qing dynasty. Although the Japanese elite were keen importers of Chinese porcelain from early on, they were not able to make their own until the arrival of Korean potters that were taken captive during

870-507: A thin layer of bitumen underneath to help adhesion. The next advances involved two simple processes. The first involves gold leaf, which is gold that is hammered or cut into very thin sheets. Gold leaf is often thinner than standard paper today, and when held to the light is semi-transparent. In ancient times it was typically about ten times thicker than today, and perhaps half that in the Middle Ages . If gilding on canvas or on wood,

957-484: A wider range of colours. Like many earlier wares, modern porcelains are often biscuit -fired at around 1,000 °C (1,830 °F), coated with glaze and then sent for a second glaze -firing at a temperature of about 1,300 °C (2,370 °F) or greater. Another early method is "once-fired", where the glaze is applied to the unfired body and the two fired together in a single operation. In this process, "green" (unfired) ceramic wares are heated to high temperatures in

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1044-439: Is a type of gilding brush used for transferring sheets of metal leaf to either a surface that has been prepared to accept the leaf or to a gilder's block where the leaf is then cut with a gilder's knife into smaller portions before being transferred to the prepared surface. The hairs on a gilder's tip are usually made of either blue squirrel hair or the hair of a badger (sometimes other hairs are also used, such as that of

1131-520: Is a very common shape in Korea. Korean celadon comes in a variety of colors, from turquoise to putty . Additionally, in the late 13th century, the Inlay technique of expressing pigmented patterns by filling the hollow parts of pottery with white and red clay was frequently used. The main difference from those in China is that many specimens have inlay decoration under the glaze. Most Korean ceramics from

1218-401: Is applied to numerous and diverse surfaces and by various processes. More traditional techniques still form an important part of framemaking and are sometimes still employed in general woodworking , cabinet -work, decorative painting and interior decoration , bookbinding , and ornamental leather work, and in the decoration of pottery , porcelain, and glass . Herodotus mentions that

1305-807: Is currently in the collection of the Victoria and Albert Museum in London . It was purchased by the V&;A with the assistance of the Worshipful Company of Goldsmiths and the National Art Collections Fund . Parcel-gilt Gilding gives an object a gold appearance at a fraction of the cost of creating a solid gold object. In addition, a solid gold piece would often be too soft or too heavy for practical use. A gilt surface also does not tarnish as silver does. Modern gilding

1392-416: Is determined by measuring the increase in content of water required to change a clay from a solid state bordering on the plastic, to a plastic state bordering on the liquid, though the term is also used less formally to describe the ease with which a clay may be worked. Clays used for porcelain are generally of lower plasticity than many other pottery clays. They wet very quickly, meaning that small changes in

1479-542: Is now made worldwide, including in China. The English had read the letters of Jesuit missionary François Xavier d'Entrecolles , which described Chinese porcelain manufacturing secrets in detail. One writer has speculated that a misunderstanding of the text could possibly have been responsible for the first attempts to use bone-ash as an ingredient in English porcelain, although this is not supported by modern researchers and historians. Traditionally, English bone china

1566-433: Is performed by a solution of gold in aqua regia , applied by dipping a linen rag into the solution, burning it, and rubbing the black and heavy ashes on the silver with the finger or a piece of leather or cork. Wet gilding is effected by means of a dilute solution of gold(III) chloride in aqua regia with twice its quantity of ether . The liquids are agitated and allowed to rest, to allow the ether to separate and float on

1653-405: Is then applied with a small brush, and as it evaporates it deposits the gold, which can now be heated and polished. For small delicate figures, a pen or a fine brush may be used for laying on the ether solution. The gold(III) chloride can also be dissolved in water in electroless plating wherein the gold is slowly reduced out of solution onto the surface to be gilded. When this technique is used on

1740-423: Is then exposed to heat, before being quenched in water. By this method, the color of the gilding is further improved and brought nearer to that of gold, probably by removing any particles of copper that may have been on the gilt surface. This process, when skillfully carried out, produces gilding of great solidity and beauty. This method of gilding metallic objects was formerly widespread, but fell into disuse as

1827-435: Is wrought or chased, the application of mercury before the amalgam is applied allows for it to be more easily spread. When the surface of the metal is plain, the amalgam can be applied to it directly. When no such preparation is applied, the surface to be gilded is simply bitten and cleaned with nitric acid . A deposit of mercury is obtained on a metallic surface by means of quicksilver water, a solution of mercury(II) nitrate ,

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1914-857: The Baranovsky Porcelain Factory and at the Experimental Ceramic and Artistic Plant in Kyiv, was Oksana Zhnikrup , whose porcelain figures of the ballet and the circus were widely known. The pastes produced by combining clay and powdered glass ( frit ) were called Frittenporzellan in Germany and frita in Spain. In France they were known as pâte tendre and in England as "soft-paste". They appear to have been given this name because they do not easily retain their shape in

2001-581: The Egyptians gilded wood and metals, and many such objects have been excavated. Certain Ancient Greek statues of great prestige were chryselephantine , i.e., made of gold (for the clothing) and ivory (for the flesh); these however, were constructed with sheets of gold over a timber framework, not gilded. Extensive ornamental gilding was also used in the ceiling coffers of the Propylaea . Pliny

2088-530: The Islamic world , where they were highly prized. Eventually, porcelain and the expertise required to create it began to spread into other areas of East Asia. During the Song dynasty (960–1279 CE), artistry and production had reached new heights. The manufacture of porcelain became highly organised, and the dragon kilns excavated from this period could fire as many as 25,000 pieces at a time, and over 100,000 by

2175-525: The Japanese invasions of Korea (1592–1598) . They brought an improved type of kiln, and one of them spotted a source of porcelain clay near Arita , and before long several kilns had started in the region. At first their wares were similar to the cheaper and cruder Chinese porcelains with underglaze blue decoration that were already widely sold in Japan; this style was to continue for cheaper everyday wares until

2262-705: The Joseon Dynasty (1392-1910) are of excellent decorative quality. It usually has a melon shape and is asymmetrical. Imported Chinese porcelains were held in such great esteem in Europe that in English china became a commonly used synonym for the Italian-derived porcelain . The first mention of porcelain in Europe is in Il Milione by Marco Polo in the 13th century. Apart from copying Chinese porcelain in faience ( tin glazed earthenware ),

2349-530: The Shang dynasty (1600–1046 BCE). By the time of the Eastern Han dynasty (25–220 CE) these early glazed ceramic wares had developed into porcelain, which Chinese defined as high-fired ware. By the late Sui dynasty (581–618 CE) and early Tang dynasty (618–907 CE), the now-standard requirements of whiteness and translucency had been achieved, in types such as Ding ware . The wares were already exported to

2436-600: The Spaniards . The surface is etched with acids, resulting in a surface of porous gold. The porous surface is then burnished down, resulting in a shiny gold surface. The results fooled the conquistadors into thinking they had massive quantities of pure gold. The results startled modern archaeologists , because at first the pieces resemble electroplated articles. Keum-boo is a special Korean technique of silver-gilding, using depletion gilding . The gilding of decorative ceramics has been undertaken for centuries, with

2523-615: The 18th century was based on soft-paste porcelain, and refined earthenwares such as creamware , which could compete with porcelain, and had devastated the faience industries of France and other continental countries by the end of the century. Most English porcelain from the late 18th century to the present is bone china. In the twenty-five years after Briand's demonstration, a number of factories were founded in England to make soft-paste tableware and figures: Porcelain has been used for electrical insulators since at least 1878, with another source reporting earlier use of porcelain insulators on

2610-604: The 20th century. Exports to Europe began around 1660, through the Chinese and the Dutch East India Company , the only Europeans allowed a trading presence. Chinese exports had been seriously disrupted by civil wars as the Ming dynasty fell apart, and the Japanese exports increased rapidly to fill the gap. At first the wares used European shapes and mostly Chinese decoration, as the Chinese had done, but gradually original Japanese styles developed. Nabeshima ware

2697-615: The Elder recorded that the first gilding seen at Rome was after the destruction of Carthage , under the censorship of Lucius Mummius , when the Romans began to gild the ceilings of their temples and palaces, the Capitol being the first place where this process was used. Gilding became a popular luxury within Rome soon after the introduction of the technique, with gilding soon being seen used on

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2784-622: The French Jesuit father Francois Xavier d'Entrecolles and soon published in the Lettres édifiantes et curieuses de Chine par des missionnaires jésuites . The secrets, which d'Entrecolles read about and witnessed in China, were now known and began seeing use in Europe. Von Tschirnhaus along with Johann Friedrich Böttger were employed by Augustus II , King of Poland and Elector of Saxony , who sponsored their work in Dresden and in

2871-604: The German state of Saxony , the search concluded in 1708 when Ehrenfried Walther von Tschirnhaus produced a hard, white, translucent type of porcelain specimen with a combination of ingredients, including kaolin and alabaster , mined from a Saxon mine in Colditz . It was a closely guarded trade secret of the Saxon enterprise. In 1712, many of the elaborate Chinese porcelain manufacturing secrets were revealed throughout Europe by

2958-591: The Hewelke factory, which only lasted from 1758 to 1763. The soft-paste Cozzi factory fared better, lasting from 1764 to 1812. The Le Nove factory produced from about 1752 to 1773, then was revived from 1781 to 1802. The first soft-paste in England was demonstrated by Thomas Briand to the Royal Society in 1742 and is believed to have been based on the Saint-Cloud formula. In 1749, Thomas Frye took out

3045-497: The Ming dynasty, and in 1598, Dutch merchants followed. Some porcelains were more highly valued than others in imperial China. The most valued types can be identified by their association with the court, either as tribute offerings, or as products of kilns under imperial supervision. Since the Yuan dynasty , the largest and best centre of production has made Jingdezhen porcelain . During the Ming dynasty, Jingdezhen porcelain had become

3132-511: The basic ingredients for most continental European hard-paste porcelains. Soft-paste porcelains date back to early attempts by European potters to replicate Chinese porcelain by using mixtures of clay and frit . Soapstone and lime are known to have been included in these compositions. These wares were not yet actual porcelain wares, as they were neither hard nor vitrified by firing kaolin clay at high temperatures. As these early formulations suffered from high pyroplastic deformation, or slumping in

3219-434: The body; the mercury used in the process also evaporates into the atmosphere, thus polluting it. This process has generally been supplanted by the electroplating of gold over a nickel substrate , which is more economical and less dangerous. In depletion gilding, a subtractive process discovered in pre-Columbian Mesoamerica , articles are fabricated by various techniques from an alloy of copper and gold, named tumbaga by

3306-412: The brush, but this is not so) and then laying the edge of the brush along the edge of the piece of metal foil. The jelly will cause the metal to adhere very gently to the hairs and allow the piece to be floated from the paper surface on which had previously been stored. Because the leaf is so thin, this must be done in a room with extremely still air, and the user of the tip usually does not breathe until

3393-436: The ceramic body approaches whiteness and translucency. In 2021, the global market for porcelain tableware was estimated to be worth US$ 22.1 billion. Hard-paste porcelain was invented in China, and it was also used in Japanese porcelain . Most of the finest quality porcelain wares are made of this material. The earliest European porcelains were produced at the Meissen factory in the early 18th century; they were formed from

3480-498: The content of water can produce large changes in workability. Thus, the range of water content within which these clays can be worked is very narrow and consequently must be carefully controlled. Porcelain can be made using all the shaping techniques for pottery. Biscuit porcelain is unglazed porcelain treated as a finished product, mostly for figures and sculpture. Unlike their lower-fired counterparts, porcelain wares do not need glazing to render them impermeable to liquids and for

3567-476: The craft into the native population in the Philippines , although oral literature from Cebu in the central Philippines have noted that porcelain were already being produced by the natives locally during the time of Cebu's early rulers, prior to the arrival of colonizers in the 16th century. Olive green glaze was introduced in the late Silla Dynasty . Most ceramics from Silla are generally leaf-shaped, which

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3654-426: The dangers of mercury toxicity became known. Since fire-gilding requires that the mercury be volatilized to drive off the mercury and leave the gold behind on the surface, it is extremely dangerous. Breathing the fumes generated by this process can quickly result in serious health problems, such as neurological damage and endocrine disorders , since inhalation is a very efficient route for mercuric compounds to enter

3741-420: The decorated ware is fired in a kiln to fuse the gold to the glaze and hence ensure its permanence. The most important factors affecting coating quality are the composition of applied gold, the state of the surface before application, the thickness of the layer and the firing conditions. A number of different forms and compositions are available to apply gold to ceramic, and these include: A gilder's tip

3828-425: The definition used) at some point about 2,000 to 1,200 years ago. It slowly spread to other East Asian countries, then to Europe, and eventually to the rest of the world. The European name, porcelain in English, comes from the old Italian porcellana ( cowrie shell ) because of its resemblance to the surface of the shell. Porcelain is also referred to as china or fine china in some English-speaking countries, as it

3915-427: The dining tables and buffets of the rich. Apart from having an obvious ornamental quality, their function was to hold personal pieces of cutlery or, as in this case, salt or spices —there is a detachable compartment on the rear deck, which was presumably passed around the table. This nautilus shell was a rare natural curiosity. The Burghley Nef would have been placed in front of the most important person at table as

4002-554: The end of the period. While Xing ware is regarded as among the greatest of the Tang dynasty porcelain, Ding ware became the premier porcelain of the Song dynasty. By the Ming dynasty , production of the finest wares for the court was concentrated in a single city, and Jingdezhen porcelain , originally owned by the imperial government, remains the centre of Chinese porcelain production. By

4089-405: The following substances: red ochre , verdigris , copper scales, alum , vitriol , and borax . By this operation the color of the gilding is heightened, as a result of the perfect dissipation of some of the remaining mercury. The gilt surface is then covered over with potassium nitrate , alum or other salts, ground together, and mixed into a paste with water or weak ammonia . The piece of metal

4176-475: The formation of the mineral mullite within the body at these high temperatures. End applications include tableware , decorative ware such as figurines , and products in technology and industry such as electrical insulators and laboratory ware. The manufacturing process used for porcelain is similar to that used for earthenware and stoneware , the two other main types of pottery, although it can be more challenging to produce. It has usually been regarded as

4263-446: The gold as pigment in paint: the artist ground the gold into a fine powder and mixed it with a binder such as gum arabic . The resulting gold paint, called shell gold , was applied in the same way as with any paint. Sometimes, after either gold-leafing or gold-painting, the artist would heat the piece enough to melt the gold slightly, ensuring an even coat. These techniques remained the only alternatives for materials like wood, leather,

4350-467: The gold leaf was layered on using a gilder's tip and left to dry before being burnished with a piece of polished agate . Those gilding on canvas and parchment also sometimes employed stiffly-beaten egg whites ("glair"), gum , and/or Armenian bole as sizing, though egg whites and gum both become brittle over time, causing the gold leaf to crack and detach, and so honey was sometimes added to make them more flexible. Other gilding processes involved using

4437-526: The kiln at high temperatures, they were uneconomic to produce and of low quality. Formulations were later developed based on kaolin with quartz, feldspars, nepheline syenite , or other feldspathic rocks. These are technically superior and continue to be produced. Soft-paste porcelains are fired at lower temperatures than hard-paste porcelains; therefore, these wares are generally less hard than hard-paste porcelains. Although originally developed in England in 1748 to compete with imported porcelain, bone china

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4524-454: The leaf is in place. Once the leaf has settled, it is often burnished with polished piece of agate to achieve a high degree of brilliance. Gilder's tips are necessary because touching the metal leaf with the finger tips would immediately cause the leaf to lose its coherent flattened shape and crumble irretrievably into metallic dust which then cannot be used for any purpose. [REDACTED]   This article incorporates text from

4611-402: The mercury has evaporated, indicated by the surface taking on a dull yellow color, the metal must undergo further steps to exhibit its fine gold color. First, the gilded surface is rubbed with a scratch brush of brass wire, until its surface is smooth. It is then covered with gilding wax, and again exposed to fire until the wax is burnt off. Gilding wax is composed of beeswax mixed with some of

4698-574: The metallic surface at a temperature just under red-hot, pressing the leaf on with a burnisher, then reheating when additional leaf may be laid on. The process is completed by cold burnishing. "Overlaying" or folding or hammering on gold foil or gold leaf is the simplest and most ancient method, and is mentioned in Homer 's Odyssey and the Old Testament . The Ram in a Thicket (2600–2400 BC) from Ur describes this technique used on wood, with

4785-404: The mixture is stirred with an iron rod, the gold is totally absorbed. The proportion of mercury to gold is generally six or eight to one. When the amalgam is cold, it is squeezed through chamois leather to separate the superfluous mercury; the gold, with about twice its weight of mercury, remains behind, forming a yellowish silvery mass with the consistency of butter. When the metal to be gilded

4872-401: The most part are glazed for decorative purposes and to make them resistant to dirt and staining. Many types of glaze, such as the iron-containing glaze used on the celadon wares of Longquan , were designed specifically for their striking effects on porcelain. Porcelain often receives underglaze decoration using pigments that include cobalt oxide and copper, or overglaze enamels , allowing

4959-422: The most prestigious type of pottery due to its delicacy, strength, and high degree of whiteness. It is frequently both glazed and decorated. Though definitions vary, porcelain can be divided into three main categories: hard-paste , soft-paste , and bone china . The categories differ in the composition of the body and the firing conditions. Porcelain slowly evolved in China and was finally achieved (depending on

5046-414: The nitric acid attacking the metal to which it is applied, and thus leaving a film of free metallic mercury. After the amalgam is equally spread over the prepared surface of the metal, the mercury is then carefully volatilized with heat just sufficient to do so, as a temperature too high may cause part of the gold to be driven off, or otherwise run together, leaving some of the metal surface bare. When

5133-419: The operations in which gold leaf is prepared, and the processes to mechanically attach the gold onto surfaces. The techniques include burnishing , water gilding and oil-gilding used by wood carvers and gilders; and the gilding operations of the house decorator, sign painter, bookbinder , the paper stainer and several others. Polished iron, steel and other metals are gilded mechanically by applying gold leaf to

5220-427: The permanence and brightness of gold appealing to designers. Both porcelain and earthenware are commonly decorated with gold, and in the late 1970s it was reported that 5 tonnes of gold were used annually for the decoration of these products. Some wall tiles also have gold decoration. Application techniques include spraying , brushing , banding machines, and direct or indirect screen-printing . After application

5307-480: The porcelain to a maximum of 1200 °C in an oxidising atmosphere, whereas reduction firing is standard practice at Chinese manufacturers. In 2018, a porcelain bushing insulator manufactured by NGK in Handa , Aichi Prefecture , Japan was certified as the world's largest ceramic structure by Guinness World Records . It is 11.3 m in height and 1.5 m in diameter. The global market for high-voltage insulators

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5394-442: The properties of the porcelain, such as ASTM C515. A porcelain tile has been defined as 'a ceramic mosaic tile or paver that is generally made by the dust-pressed method of a composition resulting in a tile that is dense, fine-grained, and smooth with sharply formed face, usually impervious and having colors of the porcelain type which are usually of a clear, luminous type or granular blend thereof.' Manufacturers are found across

5481-727: The research was still being supervised by Tschirnhaus; however, he died in October of that year. It was left to Böttger to report to Augustus in March 1709 that he could make porcelain. For this reason, credit for the European discovery of porcelain is traditionally ascribed to him rather than Tschirnhaus. The Meissen factory was established in 1710 after the development of a kiln and a glaze suitable for use with Böttger's porcelain, which required firing at temperatures of up to 1,400 °C (2,552 °F) to achieve translucence. Meissen porcelain

5568-499: The second surface of glass and backed with silver, it is known as " Angel gilding ". Fire-gilding or wash-gilding is a process by which an amalgam of gold is applied to metallic surfaces, the mercury being subsequently volatilized , leaving a film of gold or an amalgam containing 13 to 16% mercury. In the preparation of the amalgam, the gold must first be reduced to thin plates or grains, which are heated red-hot, and thrown into previously heated mercury, until it begins to smoke. When

5655-510: The soft-paste Medici porcelain in 16th-century Florence was the first real European attempt to reproduce it, with little success. Early in the 16th century, Portuguese traders returned home with samples of kaolin, which they discovered in China to be essential in the production of porcelain wares. However, the Chinese techniques and composition used to manufacture porcelain were not yet fully understood. Countless experiments to produce porcelain had unpredictable results and met with failure. In

5742-412: The start of the 19th century, and as Japan opened to trade in the second half, exports expanded hugely and quality generally declined. Much traditional porcelain continues to replicate older methods of production and styles, and there are several modern industrial manufacturers. By the early 1900s, Filipino porcelain artisans working in Japanese porcelain centres for much of their lives, later on introduced

5829-420: The surface of the acid. The whole mixture is then poured into a separating funnel with a small aperture, and allowed to rest for some time, when the acid is run off from below and the gold dissolved in ether separated. The ether will be found to have taken up all the gold from the acid, and may be used for gilding iron or steel, for which purpose the metal is polished with fine emery and spirits of wine . The ether

5916-448: The surface was often first coated with gesso . "Gesso" is a substance made of finely ground gypsum or chalk mixed with glue. Once the coating of gesso had been applied, allowed to dry, and smoothed, it was re-wet with a sizing made of rabbit-skin glue and water ("water gilding", which allows the surface to be subsequently burnished to a mirror-like finish) or boiled linseed oil mixed with litharge ("oil gilding", which does not) and

6003-509: The telegraph line between Frankfurt and Berlin. It is widely used for insulators in electrical power transmission system due to its high stability of electrical, mechanical and thermal properties even in harsh environments. A body for electrical porcelain typically contains varying proportions of ball clay, kaolin, feldspar, quartz, calcined alumina and calcined bauxite. A variety of secondary materials can also be used, such as binders which burn off during firing. UK manufacturers typically fired

6090-540: The term "porcelain" lacks a universal definition and has "been applied in an unsystematic fashion to substances of diverse kinds that have only certain surface-qualities in common". Traditionally, East Asia only classifies pottery into low-fired wares (earthenware) and high-fired wares (often translated as porcelain), the latter also including what Europeans call "stoneware", which is high-fired but not generally white or translucent. Terms such as "proto-porcelain", "porcellaneous", or "near-porcelain" may be used in cases where

6177-486: The time of the Ming dynasty (1368–1644 CE), porcelain wares were being exported to Asia and Europe. Some of the most well-known Chinese porcelain art styles arrived in Europe during this era, such as the coveted " blue-and-white " wares. The Ming dynasty controlled much of the porcelain trade, which was expanded to Asia, Africa and Europe via the Silk Road . In 1517, Portuguese merchants began direct trade by sea with

6264-483: The town of Meissen . Tschirnhaus had a wide knowledge of science and had been involved in the European quest to perfect porcelain manufacture when, in 1705, Böttger was appointed to assist him in this task. Böttger had originally been trained as a pharmacist; after he turned to alchemical research, he claimed to have known the secret of transmuting dross into gold, which attracted the attention of Augustus. Imprisoned by Augustus as an incentive to hasten his research, Böttger

6351-605: The unfired material is "body"; for example, when buying materials a potter might order an amount of porcelain body from a vendor. The composition of porcelain is highly variable, but the clay mineral kaolinite is often a raw material. Other raw materials can include feldspar, ball clay , glass, bone ash , steatite , quartz, petuntse and alabaster . The clays used are often described as being long or short, depending on their plasticity . Long clays are cohesive (sticky) and have high plasticity; short clays are less cohesive and have lower plasticity. In soil mechanics , plasticity

6438-422: The vellum pages of illuminated manuscripts , and gilt-edged stock. Chemical gilding embraces those processes in which the gold is at some stage of chemical combination. These include cold gilding, wet gilding, fire gilding and depletion gilding. In cold gilding, the gold is obtained in a state of extremely fine division (i.e. atomized or finely powdered), and applied by mechanical means. Cold gilding on silver

6525-425: The walls, vaults and inside the houses of anyone who could afford it, including the poor. Owing to the comparative thickness of the gold leaf used in ancient gilding, the traces of it that remain are remarkably brilliant and solid. Fire-gilding of metal goes back at least to the 4th century BC. Mercury -gilding was invented by Chinese Daoists in the 4th century CE and was used for the gilding of bronze plaques. It

6612-617: The wet state, or because they tend to slump in the kiln under high temperature, or because the body and the glaze can be easily scratched. Experiments at Rouen produced the earliest soft-paste in France, but the first important French soft-paste porcelain was made at the Saint-Cloud factory before 1702. Soft-paste factories were established with the Chantilly manufactory in 1730 and at Mennecy in 1750. The Vincennes porcelain factory

6699-630: The world with Italy being the global leader, producing over 380 million square metres in 2006. Historic examples of rooms decorated entirely in porcelain tiles can be found in several palaces including ones at Galleria Sabauda in Turin , Museo di Doccia in Sesto Fiorentino , Museo di Capodimonte in Naples, the Royal Palace of Madrid and the nearby Royal Palace of Aranjuez . and

6786-545: Was once-fired , or green-fired . It was noted for its great resistance to thermal shock ; a visitor to the factory in Böttger's time reported having seen a white-hot teapot being removed from the kiln and dropped into cold water without damage. Although widely disbelieved this has been replicated in modern times. In 1744, Elizabeth of Russia signed an agreement to establish the first porcelain manufactory; previously it had to be imported. The technology of making "white gold"

6873-747: Was carefully hidden by its creators. Peter the Great had tried to reveal the "big porcelain secret", and sent an agent to the Meissen factory, and finally hired a porcelain master from abroad. This relied on the research of the Russian scientist Dmitry Ivanovich Vinogradov . His development of porcelain manufacturing technology was not based on secrets learned through third parties, but was the result of painstaking work and careful analysis. Thanks to this, by 1760, Imperial Porcelain Factory, Saint Petersburg became

6960-428: Was established in 1740, moving to larger premises at Sèvres in 1756. Vincennes soft-paste was whiter and freer of imperfections than any of its French rivals, which put Vincennes/Sèvres porcelain in the leading position in France and throughout the whole of Europe in the second half of the 18th century. Doccia porcelain of Florence was founded in 1735 and remains in production, unlike Capodimonte porcelain which

7047-506: Was estimated to be worth US$ 4.95 billion in 2015, of which porcelain accounts for just over 48%. A type of porcelain characterised by low thermal expansion, high mechanical strength and high chemical resistance. Used for laboratory ware, such as reaction vessels, combustion boats, evaporating dishes and Büchner funnels . Raw materials for the body include kaolin, quartz, feldspar, calcined alumina, and possibly also low percentages of other materials. A number of International standards specify

7134-509: Was first seen in imports from China during the 17th century. Properties associated with porcelain include low permeability and elasticity ; considerable strength , hardness , whiteness, translucency , and resonance ; and a high resistance to corrosive chemicals and thermal shock . Porcelain has been described as being "completely vitrified, hard, impermeable (even before glazing), white or artificially coloured, translucent (except when of considerable thickness), and resonant". However,

7221-531: Was known to Pliny (33,20,64–5), Vitruvius (8,8,4) and in the Early Medieval period to Theophilus (De Diversis Artibus Book III). In Europe, silver-gilt has always been more common than gilt-bronze, but in China the opposite has been the case. The ancient Chinese also developed the gilding of porcelain , which was later taken up by the French and other European potters. Mechanical gilding includes all

7308-409: Was made from two parts of bone ash , one part of kaolin , and one part of china stone , although the latter has been replaced by feldspars from non-UK sources. Kaolin is the primary material from which porcelain is made, even though clay minerals might account for only a small proportion of the whole. The word paste is an old term for both unfired and fired materials. A more common terminology for

7395-499: Was moved from Naples to Madrid by its royal owner , after producing from 1743 to 1759. After a gap of 15 years Naples porcelain was produced from 1771 to 1806, specializing in Neoclassical styles. All these were very successful, with large outputs of high-quality wares. In and around Venice , Francesco Vezzi was producing hard-paste from around 1720 to 1735; survivals of Vezzi porcelain are very rare, but less so than from

7482-399: Was obliged to work with other alchemists in the futile search for transmutation and was eventually assigned to assist Tschirnhaus. One of the first results of the collaboration between the two was the development of a red stoneware that resembled that of Yixing . A workshop note records that the first specimen of hard, white and vitrified European porcelain was produced in 1708. At the time,

7569-462: Was produced in kilns owned by the families of feudal lords, and were decorated in the Japanese tradition, much of it related to textile design. This was not initially exported, but used for gifts to other aristocratic families. Imari ware and Kakiemon are broad terms for styles of export porcelain with overglaze "enamelled" decoration begun in the early period, both with many sub-types. A great range of styles and manufacturing centres were in use by

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