Porcelain is a ceramic material made by heating raw materials, generally including clay in the form of kaolin, in a kiln to temperatures between 1,200 °C (2,192 °F) and 1,400 °C (2,552 °F). The word ceramic is derived from the Greek word κεραμικός ( keramikos) Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Kilns are thermally insulated chambers or Ovens in which controlled temperature regimes are produced The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The toughness, strength, and translucence of porcelain arise mainly from the formation of glass and the mineral mullite within the fired body at these high temperatures . Mullite, or porcelainite, is a rare Clay Mineral with the chemical composition Al 6 Si 2 O 13
Porcelain derives its present name from its resemblance to the cowrie shell, which in old Italian porcellana, from feminine of porcellano, of a young sow (from the shell's resemblance to a pig's back), from porcella, young sow, diminutive of porca, sow, from Latin, feminine of porcus, pig. Cowry, also sometimes spelled cowrie, plural always cowries, is the Common name for a group of small to large sea Snails marine Italian ( or lingua italiana) is a Romance language spoken by about 63 million people as a First language, primarily in Italy. [1] 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. A material is said to be elastic if it deforms under stress (e In Materials science, the strength of a material refers to the material's ability to resist an applied force Hardness refers to various properties of Matter in the Solid phase that give it high resistance to various kinds of shape change when Force White is a Color, the perception which is evoked by Light that stimulates all three types of color sensitive Cone cells in the Human eye In Optics, transparency (also called pellucidity) is the Material property of allowing In Physics, resonance is the tendency of a system to Oscillate at maximum Amplitude at certain frequencies, known as the system's Thermal shock is the name given to cracking as a result of rapid temperature change
For the purposes of trade, the Combined Nomenclature of the European Communities defines porcelain as being "completely vitrified, hard, impermeable (even before glazing), white or artificially coloured, translucent (except when of considerable thickness) and resonant. " However, the term porcelain lacks a universal definition and has "been applied in a very unsystematic fashion to substances of diverse kinds which have only certain surface-qualities in common" (Burton 1906).
Porcelain is used to make table, kitchen, sanitary, and decorative wares; objects of fine art; and tiles. A tile is a manufactured piece of hard-wearing material such as Ceramic, stone, metal or even Glass. Its high resistance to the passage of electricity makes porcelain an excellent insulator. An insulator, also called a Dielectric, is a material that resists the flow of Electric current. Dental porcelain is used to make false teeth, caps and crowns. Dental porcelain (also known as dental ceramic) is a Porcelain used by a Dental technician to create Biocompatible lifelike crowns
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The most common uses of porcelain are the creation of artistic objects and the production of more utilitarian wares. It is difficult to distinguish between stoneware and porcelain because this depends upon how the terms are defined. Stoneware a Vitreous or semivitreous ceramic ware of fine texture made primarily from nonrefactory fire clay A useful working definition of porcelain might include a broad range of ceramic wares, including some that could be classified as stoneware.
Clay is generally thought to be the primary material from which porcelain is made, even though clay minerals might account for only a small proportion of the whole. Pottery is the Ceramic ware made by potters It also refers to a group of materials that includes Earthenware, Stoneware Chinese ceramic ware is an Artform that has been developing since the dynastic periods. Emperor Qianlong (Chinese 乾隆 Qiánlóng, Wade-Giles' Ch'ien-Lung', Mongolian Tengeriig Tetgesen Khaan, born Hongli (弘历 September Year 1735 ( MDCCXXXV) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Year 1796 ( MDCCXCVI) was a Leap year starting on Friday (link will display the full calendar of the Gregorian calendar (or a Leap year The word "paste" is an old term for both the unfired and fired material. A more common terminology these days for 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 significant component. Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Other materials can include feldspar, ball clay, glass, bone ash, steatite, quartz, petuntse and alabaster; further information on these formulations is given "soft-paste porcelain. Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. Ball clays are kaolinitic Sedimentary Clays that commonly consist of 20-80% kaolinite 10-25% Mica, 6-65% Quartz. Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many Bone ash is the white powdery ash left from the burning ( Calcination) of Bones It is primarily composed of Calcium phosphate. Soapstone (also known as steatite or soaprock) is a Metamorphic rock, a talc- Schist. Quartz (from German) is the most abundant Mineral in the Earth 's Continental crust (although Feldspar is more common in Petuntse (from 白墩子 in Pinyin: bai2 dun1 zi0 also spelled petunse, is a historic term for a wide range of micaceous or feldspathic rocks Alabaster is a name applied to varieties of two distinct Minerals Gypsum (a hydrous sulfate of Calcium) and Calcite "Soft-paste porcelain" is a type of a Ceramic material but it lacks a more specific universally agreed definition "
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 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 facility with which a clay may be worked. Soil mechanics is a discipline that applies principles of Engineering mechanics, e Clays used for porcelain are generally of lower plasticity and are shorter than many other pottery clays. They wet very quickly, meaning that small changes in 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 the loss or gain of water during storage and throwing or forming must be carefully controlled to keep the clay from becoming too wet or too dry to manipulate. This property also contributes to porcelain's use as a slipcasting body. Slipcasting is a technique for the mass-production of Pottery, especially for shapes not easily made on a wheel
The following section provides background information on the methods used to form, decorate, finish, glaze, and fire ceramic wares.
Forming. The relatively low plasticity of the material used for making porcelain make shaping the clay difficult. In the case of throwing on a potters wheel it can be seen as pulling clay upwards and outwards into a required shape and potters often speak of pulling when forming a piece on a wheel, but the term is misleading; clay in a plastic condition cannot be pulled without breaking. The process of throwing is in fact one of remarkable complexity. To the casual observer, throwing carried out by an expert potter appears to be a graceful and almost effortless activity, but this masks the fact that a rotating mass of clay possesses energy and momentum in an abundance that will, given the slightest mishandling, rapidly cause the workpiece to become uncontrollable.
Glazing. Unlike their lower-fired counterparts, porcelain wares do not need glazing to render them impermeable to liquids and for the most part are glazed for decorative purposes and to make them resistant to dirt and staining. Great detail is given in the glaze article. Glaze is a layer or coating of a Vitreous substance which has been fired to fuse to a ceramic object to color decorate strengthen or waterproof it 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. Longquan celadon (龍泉青磁 refers to Chinese Celadon to have produced in Longguan (龍泉 kilns which were largely located in the Zhejiang prefecture
Decoration. Korea is a geographic area composed of two sovereign countries a civilization and a former state situated on the Korean Peninsula in East Asia. Celadon is a term for Ceramics denoting both a type glaze, and a ware of a specific color also called celadon. The Goryeo Dynasty ( 918 - 1392) (also spelled Koryŏ was a Sovereign state established in 918 by Taejo Wang Kon. Porcelain wares may be decorated under the glaze using pigments that include cobalt and copper or over the glaze using coloured enamels. In a discussion of Material science, enamel (or vitreous enamel or porcelain enamel in U Like many earlier wares, modern porcelains are often bisque-fired at around 1000 degrees Celsius, coated with glaze and then sent for a second glaze-firing at a temperature of about 1300 degrees Celsius or greater. Bisque, also biscuit is a fired piece of unglazed Ceramic ware The Celsius Temperature scale was previously known as the centigrade scale. Glaze is a layer or coating of a Vitreous substance which has been fired to fuse to a ceramic object to color decorate strengthen or waterproof it In an alternative method particularly associated with Chinese and early European porcelains, the glaze is applied to the unfired body and the two fired together in a single operation. Wares glazed in this way are described as being green-fired or once-fired.
Firing. In this process, green (unfired) ceramic wares are heated to high temperatures in a kiln to permanently set their shapes. Kilns are thermally insulated chambers or Ovens in which controlled temperature regimes are produced Porcelain is fired at a higher temperature than earthenware or stoneware so that the clay can vitrify and become non-porous. Vitrification is a process of converting a material into a Glass -like Amorphous solid that is free from any Crystalline structure either by the quick removal
Western porcelain is generally divided into the three main categories: hard-paste, soft-paste, and bone, depending on the composition of the paste, the material used to form the body of a porcelain object.
Some of the earliest European porcelains were produced at the Meissen factory in the early 18th century; they were formed from a paste composed of kaolinite, quartz, and alabaster and fired at temperatures in excess of 1,350 °C (2,462 °F), producing a porcelain of great hardness and strength. Hard-paste porcelain is a hard Ceramic that was originally made from a compound of the Feldspathic rock Petuntse and Kaolin fired at very high Meissen porcelain is the first European Hard-paste porcelain that was developed from 1708 by Ehrenfried Walther von Tschirnhaus. The 18th century lasted from 1701 to 1800 in the Gregorian calendar, in accordance with the Anno Domini / Common Era numbering system Later, the composition of the Meissen hard paste was changed and the alabaster was replaced by feldspar, allowing the pieces to be fired at lower temperatures. Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. Kaolinite, feldspar and quartz (or other forms of silica) continue to provide the basic ingredients for most continental European hard-paste porcelains. The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide
Its history dates from the early attempts by European potters to replicate Chinese porcelain by using mixtures of china clay and ground-up glass or frit; soapstone and lime were known to have also been included in some compositions. "Soft-paste porcelain" is a type of a Ceramic material but it lacks a more specific universally agreed definition As these early formulations suffered from high pyroplastic deformation, or slumping in the kiln at raised temperature, they were uneconomic to produce. Formulations were later developed based on kaolin, quartz, feldspars, nepheline syenite and other feldspathic rocks. These were technically superior and continue in production.
Although originally developed in England to compete with imported porcelain, Bone china is now made worldwide. Bone china is a type of Porcelain body first developed in Britain in which calcined Cattle bone ( Bone ash) is a major constituent Bone china is a type of Porcelain body first developed in Britain in which calcined Cattle bone ( Bone ash) is a major constituent It has been suggested that a misunderstanding of an account of porcelain manufacture in China given by a Jesuit missionary was responsible for the first attempts to use bone-ash as an ingredient of Western porcelain (in China, china clay was sometimes described as forming the bones of the paste, while the flesh was provided by refined porcelain stone). The Society of Jesus ( Latin: Societas Iesu, SJ and SI or SJ, SI) is a Catholic religious order For whatever reason, when it was first tried it was found that adding bone-ash to the paste produced a white, strong, translucent porcelain. Traditionally English bone china was made from two parts of bone-ash, one part of china clay kaolin and one part china stone (a feldspathic rock), although this has largely been replaced by feldspars from non-UK sources
Porcelain is generally believed to have originated in China; although pottery fragments dating to around 9000 BCE have been unearthed in Jiangxi province, true porcelain is thought to have first emerged during the late Eastern Han Dynasty, which lasted from 100 to 200 CE. Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 China stone is a medium grained Feldspar -rich partially decomposed Granite characterized by the absence of Iron -bearing minerals Chinese ceramic ware is an Artform that has been developing since the dynastic periods. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National ( Postal map spelling: Kiangsi is a southern province of the People's Republic of China, spanning from the banks of the Yangtze River The Han Dynasty ( 206 BC–220 AD followed the Qin Dynasty and preceded the Three Kingdoms in China.
By the Sui and Tang dynasties, porcelain had become widely produced. The Sui Dynasty ( 581 - 618 AD and in the undertaking of other construction projects including the reconstruction of the Great Wall. The Tang Dynasty ( Middle Chinese: dhɑng (June 18 618&ndashJune 4 907 was an imperial dynasty of China preceded by the Sui Dynasty and followed by Eventually, porcelain and the expertise required to create it began to spread into other areas; by the seventeenth century, it was being widely imported to Europe.
These exported Chinese porcelains of the seventeenth and eighteenth centuries were held in such great esteem in Europe that in the English language china became a commonly–used synonym for the Franco-Italian term porcelain. English is a West Germanic language originating in England and is the First language for most people in the United Kingdom, the United States After a number of false starts, such as the Medici porcelain, the European search for the secret of porcelain manufacture ended in 1708 with the discovery by Ehrenfried Walther von Tschirnhaus and Johann Friedrich Böttger of a combination of ingredients, including Colditz clay (a type of kaolinite), calcined alabaster, and quartz, that produced a hard, white, translucent porcelain. Medici porcelain was the first successful attempt in Europe to imitate Chinese porcelain. Ehrenfried Walther von Tschirnhaus (or Tschirnhausen) ( April 10, 1651 &ndash October 11, 1708) was a German Mathematician Johann Friedrich Böttger ( February 4, 1682 - March 13, 1719) was a German alchemist. Colditz (ˈkʰɔldɪt͡s is a city in the Free State of Saxony, Germany, near Leipzig, located on the banks of the river Mulde. Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Calcination (also referred to as calcining) is a thermal treatment process applied to ores and other solid materials in order to bring about a Thermal decomposition Alabaster is a name applied to varieties of two distinct Minerals Gypsum (a hydrous sulfate of Calcium) and Calcite Quartz (from German) is the most abundant Mineral in the Earth 's Continental crust (although Feldspar is more common in It appears that in this discovery technology transfer from East Asia played little part. Technology transfer is the process of sharing of skills knowledge technologies methods of manufacturing samples of manufacturing and facilities among industries universities governments
Tschirnhaus and Böttger were employed by Augustus the Strong and worked at Dresden and Meissenin the German state of Saxony. Royal titles In Latin: Augustus Secundus Dei Gratia rex Poloniae magnus dux Lithuaniae Russie Prussiae Masoviae Samogitiae Livoniae Kijoviae Volhyniae Dresden (etymologically from Old Sorbian Drežďany, meaning people of the riverside forest, Drježdźany is the Capital city of the German Meissen (in German orthography: Meißen; Sorbian: Mišno; Misena Misnia Misnensium is a Town of approximately 30000 near Tschirnhaus had a wide knowledge of European 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, it was his claim that he knew the secret of transmuting dross into gold that attracted the attention of Augustus. Imprisoned by Augustus as an incentive to hasten his research, Böttger 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 the red stoneware of Yixing. For the 8th century monk inventor and astronomer see Yi Xing.
A workshop note records that the first specimen of hard, white European porcelain was produced in January 1708. At the time, 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 true white 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 greater than 1,350 °C (2,462 °F) to achieve translucence. Meissen porcelain is the first European Hard-paste porcelain that was developed from 1708 by Ehrenfried Walther von Tschirnhaus. Meissen porcelain was once-fired, or green-fired, in the Chinese manner. 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. Thermal shock is the name given to cracking as a result of rapid temperature change Evidence to support this widely disbelieved story was given in the 1980s when the procedure was repeated in an experiment at the Massachusetts Institute of Technology.
William Cookworthy discovered deposits of china clay in Cornwall, making a considerable contribution to the development of porcelain and other whiteware ceramics in the United Kingdom. William Cookworthy ( 12 April, 1705 &ndash 17 October, 1780) was an English Quaker Minister, a successful Pharmacist Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Cornwall ( Kernow ˈkɛɹnɔʊ is the most southwesterly county of England, on the Peninsula that lies to the west of the River Tamar Cookworthy's factory at Plymouth, established in 1768, used Cornish china clay and china stone to make porcelain with a body composition similar to that of the Chinese porcelains of the early eighteenth century. Plymouth porcelain was a hard paste porcelain made in the English county of Devon in the 18th century. China stone is a medium grained Feldspar -rich partially decomposed Granite characterized by the absence of Iron -bearing minerals
In rare cases, porcelain has been used as a building material, usually in the form of large rectangular panels on exterior surfaces. The Dakin Building is an architectural award winning class A office building on the San Francisco Bay in Brisbane California. For other kinds of building materials see Hardware, Biology, Star formation. The Dakin Building in Brisbane, California, constructed in 1986, is notable for its porcelain skin. The Dakin Building is an architectural award winning class A office building on the San Francisco Bay in Brisbane California. Brisbane is a small city located in the northern part of San Mateo County California on the lower slopes of San Bruno Mountain. An older example is the Gulf Building in Houston, Texas; constructed in 1929, it had a seventy-foot long logo of porcelain on its exterior. The Gulf Building in Houston, Texas, now called the JPMorgan Chase building, is one of the preeminent
For a short time in America, porcelainized steel homes were produced in a Columbus, Ohio factory and erected throughout the United States. About 2500 were built and many remain standing today. These Lustron homes had porcelain coated steel ceilings, walls, exterior siding and roofs; they were advertised as maintenance-free, with no need for painting. The Lustron houses were prefabricated steel houses developed in the post- World War II era United States in response to the shortage of Houses for returning
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