Pavlikeni ( Bulgarian : Павликени [pɐvliˈkɛni] ) is a town in Veliko Tarnovo Province , Northern Bulgaria , about 41 kilometers from the city of Veliko Tarnovo . It is the administrative centre of the homonymous Pavlikeni Municipality . As of December 2010, the town had a population of 11,604.
124-708: Pavlikeni was a centre of ceramics and pottery in Antiquity as evidenced by the remains from Roman and Thracian times. Its name derives from the Paulicians , a Christian sect settled in Thrace by Leo the Isaurian . The modern town emerged in the 13th–14th centuries as a village initially called Marinopoltsi . During the Ottoman rule of Bulgaria , the demographics of the village changed significantly, as many Turks settled to make it
248-405: A glass (or vitreous solid) is a non-crystalline solid formed by rapid melt quenching . However, the term "glass" is often defined in a broader sense, to describe any non-crystalline ( amorphous ) solid that exhibits a glass transition when heated towards the liquid state. Glass is an amorphous solid . Although the atomic-scale structure of glass shares characteristics of the structure of
372-436: A supercooled liquid , glass exhibits all the mechanical properties of a solid. As in other amorphous solids , the atomic structure of a glass lacks the long-range periodicity observed in crystalline solids . Due to chemical bonding constraints, glasses do possess a high degree of short-range order with respect to local atomic polyhedra . The notion that glass flows to an appreciable extent over extended periods well below
496-809: A turquoise colour in glass, in contrast to copper(I) oxide (Cu 2 O) which gives a dull red-brown colour. Soda–lime sheet glass is typically used as a transparent glazing material, typically as windows in external walls of buildings. Float or rolled sheet glass products are cut to size either by scoring and snapping the material, laser cutting , water jets , or diamond-bladed saw. The glass may be thermally or chemically tempered (strengthened) for safety and bent or curved during heating. Surface coatings may be added for specific functions such as scratch resistance, blocking specific wavelengths of light (e.g. infrared or ultraviolet ), dirt-repellence (e.g. self-cleaning glass ), or switchable electrochromic coatings. Structural glazing systems represent one of
620-728: A "tile" is a construction tile or similar object, such as rectangular counters used in playing games (see tile-based game ). The word is derived from the French word tuile , which is, in turn, from the Latin word tegula , meaning a roof tile composed of fired clay. Tiles are often used to form wall murals and floor coverings, and can range from simple square tiles to complex mosaics . Tiles are most often made of ceramic , typically glazed for internal uses and unglazed for roofing, but other materials are also commonly used, such as glass, cork, concrete and other composite materials, and stone. Tiling stone
744-485: A clear "ring" sound when struck. However, lead glass cannot withstand high temperatures well. Lead oxide also facilitates the solubility of other metal oxides and is used in coloured glass. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with soda glass); this allows easier removal of bubbles and working at lower temperatures, hence its frequent use as an additive in vitreous enamels and glass solders . The high ionic radius of
868-576: A distinctive variant of Chinese, and later Japanese, developments. The celadon Goryeo ware from the Goryeo dynasty (918–1392) and early Joseon white porcelain of the following dynasty are generally regarded as the finest achievements. From the 8th to 18th centuries, glazed ceramics was important in Islamic art , usually in the form of elaborate pottery , developing on vigorous Persian and Egyptian pre-Islamic traditions in particular. Tin-opacified glazing
992-443: A green tint in thick sections. Manganese dioxide (MnO 2 ), which gives glass a purple colour, may be added to remove the green tint given by FeO. FeO and chromium(III) oxide (Cr 2 O 3 ) additives are used in the production of green bottles. Iron (III) oxide , on the other-hand, produces yellow or yellow-brown glass. Low concentrations (0.025 to 0.1%) of cobalt oxide (CoO) produce rich, deep blue cobalt glass . Chromium
1116-516: A group, in a pottery or a ceramic factory with a group designing and manufacturing the artware. In Britain and the United States, modern ceramics as an art took its inspiration in the early twentieth century from the Arts and Crafts movement, leading to the revival of pottery considered as a specifically modern craft. Such crafts emphasized traditional non-industrial production techniques, faithfulness to
1240-408: A human timescale. Silicon dioxide (SiO 2 ) is a common fundamental constituent of glass. Fused quartz is a glass made from chemically pure silica. It has very low thermal expansion and excellent resistance to thermal shock , being able to survive immersion in water while red hot, resists high temperatures (1000–1500 °C) and chemical weathering, and is very hard. It is also transparent to
1364-405: A lighter alternative to traditional glass. Molecular liquids, electrolytes , molten salts , and aqueous solutions are mixtures of different molecules or ions that do not form a covalent network but interact only through weak van der Waals forces or transient hydrogen bonds . In a mixture of three or more ionic species of dissimilar size and shape, crystallization can be so difficult that
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#17328545661631488-561: A long period at a temperature just insufficient to cause fusion. In this way, the crystalline, devitrified material, known as Réaumur's glass porcelain is produced. Although generally transparent to visible light, glasses may be opaque to other wavelengths of light . While silicate glasses are generally opaque to infrared wavelengths with a transmission cut-off at 4 μm, heavy-metal fluoride and chalcogenide glasses are transparent to infrared wavelengths of 7 to 18 μm. The addition of metallic oxides results in different coloured glasses as
1612-648: A major cause. One of these potters, Yi Sam-pyeong , discovered the raw material of porcelain in Arita and produced first true porcelain in Japan. In the 17th century, conditions in China drove some of its potters into Japan, bringing with them the knowledge to make refined porcelain. From the mid-century, the Dutch East India Company began to import Japanese porcelain into Europe. At this time, Kakiemon wares were produced at
1736-482: A mass of hot semi-molten glass, inflating it into a bubble using a hollow blowpipe, and forming it into the required shape by blowing, swinging, rolling, or moulding. While hot, the glass can be worked using hand tools, cut with shears, and additional parts such as handles or feet attached by welding. Flat glass for windows and similar applications is formed by the float glass process, developed between 1953 and 1957 by Sir Alastair Pilkington and Kenneth Bickerstaff of
1860-534: A material, "terracotta" also refers to items made out of this material. In archaeology and art history , "terracotta" is often used to describe objects such as statues, and figurines not made on a potter's wheel . A prime example is the Terracotta Army , a collection of man-sized terracotta sculptures depicting the armies of Qin Shi Huang , the first Emperor of China . It is a form of funerary art buried with
1984-718: A medium. Much studio pottery is tableware or cookware but an increasing number of studio potters produce non-functional or sculptural items. Some studio potters now prefer to call themselves ceramic artists, ceramists or simply artists. Studio pottery is represented by potters all over the world. A tile is a manufactured piece of hard-wearing material such as ceramic , stone , metal, or even glass , generally used for covering roofs, floors, walls, showers, or other objects such as tabletops. Alternatively, tile can sometimes refer to similar units made from lightweight materials such as perlite , wood , and mineral wool , typically used for wall and ceiling applications. In another sense,
2108-586: A new tradition of Azulejos developed in Spain and especially Portugal , which by the Baroque period produced extremely large painted scenes on tiles, usually in blue and white. Delftware tiles, typically with a painted design covering only one (rather small) tile, were ubiquitous in the Netherlands and widely exported over Northern Europe from the 16th century on. Several 18th-century royal palaces had porcelain rooms with
2232-453: A non-crystalline intergranular phase of grain boundaries . Glass-ceramics exhibit advantageous thermal, chemical, biological, and dielectric properties as compared to metals or organic polymers. The most commercially important property of glass-ceramics is their imperviousness to thermal shock. Thus, glass-ceramics have become extremely useful for countertop cooking and industrial processes. The negative thermal expansion coefficient (CTE) of
2356-401: A plastic resin with glass fibres . It is made by melting glass and stretching the glass into fibres. These fibres are woven together into a cloth and left to set in a plastic resin. Fibreglass has the properties of being lightweight and corrosion resistant and is a good insulator enabling its use as building insulation material and for electronic housing for consumer products. Fibreglass
2480-760: A purely Turkish village. After the Liberation of Bulgaria from Ottoman rule in 1877–1878, the Turks left to be replaced by Bulgarians from the Balkan Mountains and the villages of the plains. After the Liberation Pavlikeni developed as a centre of craftsmanship and trade, with many new buildings being constructed. Pavlikeni acquired town status in 1943 owing much to its position on the Sofia - Varna railway line. Pavlikeni Point on Greenwich Island , South Shetland Islands
2604-462: A refractive index of 1.4 to 2.4, and an Abbe number (which characterises dispersion) of 15 to 100. The refractive index may be modified by high-density (refractive index increases) or low-density (refractive index decreases) additives. Glass transparency results from the absence of grain boundaries which diffusely scatter light in polycrystalline materials. Semi-opacity due to crystallization may be induced in many glasses by maintaining them for
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#17328545661632728-598: A second is applied, and prior to the scratching or incising decoration. This is particularly useful if the base body is not of the desired colour or texture. In sharp contrast to the archaeological usage, in which the term terra sigillata refers to a whole class of pottery, in contemporary ceramic art, 'terra sigillata' describes only a watery refined slip used to facilitate the burnishing of raw clay surfaces and used to promote carbon smoke effects, in both primitive low temperature firing techniques and unglazed alternative western-style Raku firing techniques. Terra sigillata
2852-455: A smoother surface to a rough body, mask an inferior colour or for decorative effect. Slips or engobes can also be applied by painting techniques, in isolation or in several layers and colours. Sgraffito involves scratching through a layer of coloured slip to reveal a different colour or the base body underneath. Several layers of slip and/or sgraffito can be done while the pot is still in an unfired state. One colour of slip can be fired, before
2976-412: A spinning metal disk. Several alloys have been produced in layers with thicknesses exceeding 1 millimetre. These are known as bulk metallic glasses (BMG). Liquidmetal Technologies sells several zirconium -based BMGs. Batches of amorphous steel have also been produced that demonstrate mechanical properties far exceeding those found in conventional steel alloys. Experimental evidence indicates that
3100-435: A structural analogue of silica, fluoride , aluminate , phosphate , borate , and chalcogenide glasses) have physicochemical properties useful for their application in fibre-optic waveguides in communication networks and other specialised technological applications. Silica-free glasses may often have poor glass-forming tendencies. Novel techniques, including containerless processing by aerodynamic levitation (cooling
3224-413: A structurally metastable state with respect to its crystalline form, although in certain circumstances, for example in atactic polymers, there is no crystalline analogue of the amorphous phase. Glass is sometimes considered to be a liquid due to its lack of a first-order phase transition where certain thermodynamic variables such as volume , entropy and enthalpy are discontinuous through
3348-518: A wider spectral range than ordinary glass, extending from the visible further into both the UV and IR ranges, and is sometimes used where transparency to these wavelengths is necessary. Fused quartz is used for high-temperature applications such as furnace tubes, lighting tubes, melting crucibles, etc. However, its high melting temperature (1723 °C) and viscosity make it difficult to work with. Therefore, normally, other substances (fluxes) are added to lower
3472-402: Is pottery that has not been fired to vitrification and is thus permeable to water. Many types of pottery have been made from it from the earliest times, and until the 18th century it was the most common type of pottery outside the far East. Earthenware is often made from clay, quartz and feldspar . Terracotta , a type of earthenware , is a clay -based unglazed or glazed ceramic , where
3596-418: Is 3.25 × 10 /°C as compared to about 9 × 10 /°C for a typical soda–lime glass ). They are, therefore, less subject to stress caused by thermal expansion and thus less vulnerable to cracking from thermal shock . They are commonly used for e.g. labware , household cookware , and sealed beam car head lamps . The addition of lead(II) oxide into silicate glass lowers the melting point and viscosity of
3720-541: Is a stub . You can help Misplaced Pages by expanding it . Ceramics (art) Ceramic art is art made from ceramic materials, including clay . It may take varied forms, including artistic pottery , including tableware , tiles , figurines and other sculpture . As one of the plastic arts , ceramic art is a visual art . While some ceramics are considered fine art , such as pottery or sculpture, most are considered to be decorative , industrial or applied art objects. Ceramic art can be created by one person or by
3844-552: Is a common volcanic glass with high silica (SiO 2 ) content formed when felsic lava extruded from a volcano cools rapidly. Impactite is a form of glass formed by the impact of a meteorite , where Moldavite (found in central and eastern Europe), and Libyan desert glass (found in areas in the eastern Sahara , the deserts of eastern Libya and western Egypt ) are notable examples. Vitrification of quartz can also occur when lightning strikes sand , forming hollow, branching rootlike structures called fulgurites . Trinitite
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3968-702: Is a glassy residue formed from the desert floor sand at the Trinity nuclear bomb test site. Edeowie glass , found in South Australia , is proposed to originate from Pleistocene grassland fires, lightning strikes, or hypervelocity impact by one or several asteroids or comets . Naturally occurring obsidian glass was used by Stone Age societies as it fractures along very sharp edges, making it ideal for cutting tools and weapons. Glassmaking dates back at least 6000 years, long before humans had discovered how to smelt iron. Archaeological evidence suggests that
4092-439: Is a type of pottery identified by its primary decorating process where slip is placed onto the leather-hard clay body surface before firing by dipping, painting or splashing. Slip is an aqueous suspension of a clay body, which is a mixture of clays and other minerals such as quartz , feldspar and mica . A coating of white or coloured slip, known as an engobe, can be applied to the article to improve its appearance, to give
4216-418: Is a very powerful colouring agent, yielding dark green. Sulphur combined with carbon and iron salts produces amber glass ranging from yellowish to almost black. A glass melt can also acquire an amber colour from a reducing combustion atmosphere. Cadmium sulfide produces imperial red , and combined with selenium can produce shades of yellow, orange, and red. Addition of copper(II) oxide (CuO) produces
4340-449: Is achieved by homogenizing the raw materials mixture ( glass batch ), stirring the melt, and crushing and re-melting the first melt. The obtained glass is usually annealed to prevent breakage during processing. Colour in glass may be obtained by addition of homogenously distributed electrically charged ions (or colour centres ). While ordinary soda–lime glass appears colourless in thin section, iron(II) oxide (FeO) impurities produce
4464-574: Is also used as a brushable decorative colourant medium in higher temperature glazed ceramic techniques. Studio pottery is pottery made by amateur or professional artists or artisans working alone or in small groups, making unique items or short runs. Typically, all stages of manufacture are carried out by the artists themselves. Studio pottery includes functional wares such as tableware , cookware and non-functional wares such as sculpture . Studio potters can be referred to as ceramic artists, ceramists, ceramicists or as an artist who uses clay as
4588-676: Is extensively used for fibreglass , used for making glass-reinforced plastics (boats, fishing rods, etc.), top-of-stove cookware, and halogen bulb glass. The addition of barium also increases the refractive index. Thorium oxide gives glass a high refractive index and low dispersion and was formerly used in producing high-quality lenses, but due to its radioactivity has been replaced by lanthanum oxide in modern eyeglasses. Iron can be incorporated into glass to absorb infrared radiation, for example in heat-absorbing filters for movie projectors, while cerium(IV) oxide can be used for glass that absorbs ultraviolet wavelengths. Fluorine lowers
4712-455: Is in widespread use in optical systems due to its ability to refract, reflect, and transmit light following geometrical optics . The most common and oldest applications of glass in optics are as lenses , windows , mirrors , and prisms . The key optical properties refractive index , dispersion , and transmission , of glass are strongly dependent on chemical composition and, to a lesser degree, its thermal history. Optical glass typically has
4836-481: Is incorrect, as once solidified, glass stops flowing. The sags and ripples observed in old glass were already there the day it was made; manufacturing processes used in the past produced sheets with imperfect surfaces and non-uniform thickness (the near-perfect float glass used today only became widespread in the 1960s). A 2017 study computed the rate of flow of the medieval glass used in Westminster Abbey from
4960-406: Is known for its high levels of whiteness and translucency, and very high mechanical strength and chip resistance. Its high strength allows it to be produced in thinner cross-sections than other types of porcelain. Like stoneware it is vitrified , but is translucent due to differing mineral properties. From its initial development and up to the later part of the twentieth century, bone china
5084-579: Is named after Pavlikeni. After Bulgaria became a part of the European Union Pavlikeni created a project, which was an idea to improve the city as a whole by using the European funds. Pavlikeni took over a half a million to improve its conditions of the city centre "Svoboda". The project was realised starting 10 May 2012, with having 120 days to be completed in. The town had a factory for steel disc wheels and rims which export around five-eighths of
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5208-541: Is nonporous; it may or may not be glazed. One widely recognised definition is from the Combined Nomenclature of the European Communities, a European industry standard states "Stoneware, which, though dense, impermeable and hard enough to resist scratching by a steel point, differs from porcelain because it is more opaque , and normally only partially vitrified. It may be vitreous or semi-vitreous. It
5332-510: Is now the Russian Far East , providing several from between 20,000 and 10,000 BCE, although the vessels were simple utilitarian objects. Xianrendong Cave in Jiangxi province contained pottery fragments that date back to 20,000 years ago. Recent archaeological excavations at Angkor Borei (in southern Cambodia) have recovered a large number of ceramics, some of which probably date back to
5456-901: Is produced by forcing molten glass through a fine mesh by centripetal force and breaking the extruded glass fibres into short lengths using a stream of high-velocity air. The fibres are bonded with an adhesive spray and the resulting wool mat is cut and packed in rolls or panels. Besides common silica-based glasses many other inorganic and organic materials may also form glasses, including metals , aluminates , phosphates , borates , chalcogenides , fluorides , germanates (glasses based on GeO 2 ), tellurites (glasses based on TeO 2 ), antimonates (glasses based on Sb 2 O 3 ), arsenates (glasses based on As 2 O 3 ), titanates (glasses based on TiO 2 ), tantalates (glasses based on Ta 2 O 5 ), nitrates , carbonates , plastics , acrylic , and many other substances. Some of these glasses (e.g. Germanium dioxide (GeO 2 , Germania), in many respects
5580-461: Is stronger than most metals, with a theoretical tensile strength for pure, flawless glass estimated at 14 to 35 gigapascals (2,000,000 to 5,100,000 psi) due to its ability to undergo reversible compression without fracture. However, the presence of scratches, bubbles, and other microscopic flaws lead to a typical range of 14 to 175 megapascals (2,000 to 25,400 psi) in most commercial glasses. Several processes such as toughening can increase
5704-408: Is sufficiently rapid (relative to the characteristic crystallization time) then crystallization is prevented and instead, the disordered atomic configuration of the supercooled liquid is frozen into the solid state at T g . The tendency for a material to form a glass while quenched is called glass-forming ability. This ability can be predicted by the rigidity theory . Generally, a glass exists in
5828-522: Is the art and science of making objects from inorganic, non-metallic materials by the action of heat. It excludes glass and mosaic made from glass tesserae . There is a long history of ceramic art in almost all developed cultures, and often ceramic objects are all the artistic evidence left from vanished cultures, like that of the Nok in Africa over 2,000 years ago. Cultures especially noted for ceramics include
5952-436: Is transparent, easily formed, and most suitable for window glass and tableware. However, it has a high thermal expansion and poor resistance to heat. Soda–lime glass is typically used for windows , bottles , light bulbs , and jars . Borosilicate glasses (e.g. Pyrex , Duran ) typically contain 5–13% boron trioxide (B 2 O 3 ). Borosilicate glasses have fairly low coefficients of thermal expansion (7740 Pyrex CTE
6076-790: Is typically marble, onyx, granite or slate. Thinner tiles can be used on walls than on floors, which require more durable surfaces that will resist impacts. A figurine (a diminutive form of the word figure ) is a statuette that represents a human , deity , legendary creature , or animal . Figurines may be realistic or iconic , depending on the skill and intention of the creator. The earliest were made of stone or clay. In ancient Greece, many figurines were made from terracotta (see Greek terracotta figurines ). Modern versions are made of ceramic, metal, glass, wood and plastic. Figurines and miniatures are sometimes used in board games , such as chess , and tabletop role playing games . Old figurines have been used to discount some historical theories, such as
6200-436: Is usually coloured grey or brownish because of impurities in the clay used for its manufacture, and is normally glazed." Porcelain is a ceramic material made by heating materials, generally including kaolin , in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). The toughness, strength and translucence of porcelain, relative to other types of pottery , arises mainly from vitrification and
6324-617: The Chinese , Cretan , Greek , Persian , Mayan , Japanese , and Korean cultures, as well as the modern Western cultures. Elements of ceramic art, upon which different degrees of emphasis have been placed at different times, are the shape of the object, its decoration by painting, carving and other methods, and the glazing found on most ceramics. Different types of clay , when used with different minerals and firing conditions, are used to produce different types of ceramic, including earthenware, stoneware, porcelain and bone china. Earthenware
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#17328545661636448-513: The Late Bronze Age , there was a rapid growth in glassmaking technology in Egypt and Western Asia . Archaeological finds from this period include coloured glass ingots , vessels, and beads. Much early glass production relied on grinding techniques borrowed from stoneworking , such as grinding and carving glass in a cold state. The term glass has its origins in the late Roman Empire , in
6572-613: The Linear Pottery culture , Beaker culture , Globular Amphora culture , Corded Ware culture and Funnelbeaker culture , to take examples only from Neolithic Europe (approximately 7000–1800 BCE). Ceramic art has generated many styles from its own tradition, but is often closely related to contemporary sculpture and metalwork. Many times in its history styles from the usually more prestigious and expensive art of metalworking have been copied in ceramics. This can be seen in early Chinese ceramics, such as pottery and ceramic-wares of
6696-733: The Medici porcelain made in Florence . None was successful until a recipe for hard-paste porcelain was devised at the Meissen factory in Dresden in 1710. Within a few years, porcelain factories sprung up at Nymphenburg in Bavaria (1754) and Capodimonte in Naples (1743) and many other places, often financed by a local ruler. The earliest Japanese pottery was made around the 11th millennium BCE. Jōmon ware emerged in
6820-565: The Ming dynasty (1368–1644) have a wider reputation. Chinese emperors gave ceramics as diplomatic gifts on a lavish scale, and the presence of Chinese ceramics no doubt aided the development of related traditions of ceramics in Japan and Korea in particular. Until the 16th century, small quantities of expensive Chinese porcelain were imported into Europe. From the 16th century onwards attempts were made to imitate it in Europe, including soft-paste and
6944-478: The Mingei folk movement led by potters Shoji Hamada , Kawai Kajiro and others. They studied traditional methods in order to preserve native wares that were in danger of disappearing. Modern masters use ancient methods to bring pottery and porcelain to new heights of achievement at Shiga , Iga , Karatsu , Hagi , and Bizen . A few outstanding potters were designated living cultural treasures ( mukei bunkazai 無形文化財). In
7068-476: The Renaissance period in Europe, the use of large stained glass windows became much less prevalent, although stained glass had a major revival with Gothic Revival architecture in the 19th century. During the 13th century, the island of Murano , Venice , became a centre for glass making, building on medieval techniques to produce colourful ornamental pieces in large quantities. Murano glass makers developed
7192-527: The Roman glass making centre at Trier (located in current-day Germany) where the late-Latin term glesum originated, likely from a Germanic word for a transparent , lustrous substance. Glass objects have been recovered across the Roman Empire in domestic, funerary , and industrial contexts, as well as trade items in marketplaces in distant provinces. Examples of Roman glass have been found outside of
7316-482: The Russian Far East , providing several from 20,000 to 10,000 BCE, although the vessels were simple utilitarian objects. Xianrendong Cave in Jiangxi province contained pottery fragments that date back to 20,000 years ago. These early pottery containers were made well before the invention of agriculture , by mobile foragers who hunted and gathered their food during the Late Glacial Maximum. Many of
7440-465: The dielectric constant of glass. Fluorine is highly electronegative and lowers the polarizability of the material. Fluoride silicate glasses are used in the manufacture of integrated circuits as an insulator. Glass-ceramic materials contain both non-crystalline glass and crystalline ceramic phases. They are formed by controlled nucleation and partial crystallisation of a base glass by heat treatment. Crystalline grains are often embedded within
7564-436: The glass batch preparation and mixing, the raw materials are transported to the furnace. Soda–lime glass for mass production is melted in glass-melting furnaces . Smaller-scale furnaces for speciality glasses include electric melters, pot furnaces, and day tanks. After melting, homogenization and refining (removal of bubbles), the glass is formed . This may be achieved manually by glassblowing , which involves gathering
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#17328545661637688-789: The origins of chess . Tableware is the dishes or dishware used for setting a table, serving food and dining. It includes cutlery , glassware , serving dishes and other useful items for practical as well as decorative purposes. Dishes, bowls and cups may be made of ceramic, while cutlery is typically made from metal, and glassware is often made from glass or other non-ceramic materials. The quality, nature, variety and number of objects varies according to culture, religion, number of diners, cuisine and occasion. For example, Middle Eastern, Indian or Polynesian food culture and cuisine sometimes limits tableware to serving dishes, using bread or leaves as individual plates. Special occasions are usually reflected in higher quality tableware. In addition to being
7812-501: The 10th century onwards, glass was employed in stained glass windows of churches and cathedrals , with famous examples at Chartres Cathedral and the Basilica of Saint-Denis . By the 14th century, architects were designing buildings with walls of stained glass such as Sainte-Chapelle , Paris, (1203–1248) and the East end of Gloucester Cathedral . With the change in architectural style during
7936-869: The 13th century BCE. Glazed and coloured bricks were used to make low reliefs in Ancient Mesopotamia , most famously the Ishtar Gate of Babylon ( c. 575 BCE ), now partly reconstructed in Berlin , with sections elsewhere. Mesopotamian craftsmen were imported for the palaces of the Persian Empire such as Persepolis . The tradition continued, and after the Islamic conquest of Persia coloured and often painted glazed bricks or tiles became an important element in Persian architecture , and from there spread to much of
8060-461: The 1930s, which later became known as Depression glass . In the 1950s, Pilkington Bros. , England , developed the float glass process, producing high-quality distortion-free flat sheets of glass by floating on molten tin . Modern multi-story buildings are frequently constructed with curtain walls made almost entirely of glass. Laminated glass has been widely applied to vehicles for windscreens. Optical glass for spectacles has been used since
8184-503: The 6th millennium BCE and the plainer Yayoi style in about the 4th century BCE. This early pottery was soft earthenware, fired at low temperatures. The potter's wheel and a kiln capable of reaching higher temperatures and firing stoneware appeared in the 3rd or 4th centuries CE, probably brought from China via the Korean peninsula. In the 8th century, official kilns in Japan produced simple, green lead-glazed earthenware . Unglazed stoneware
8308-608: The 9th century. Pottery was produced in Raqqa , Syria , in the 8th century. Other centers for innovative ceramics in the Islamic world were Fustat (near modern Cairo ) from 975 to 1075, Damascus from 1100 to around 1600 and Tabriz from 1470 to 1550. Glass Glass is an amorphous ( non-crystalline ) solid. Because it is often transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window panes, tableware , and optics . Some common objects made of glass are named after
8432-755: The Islamic world, notably the İznik pottery of Turkey under the Ottoman Empire in the 16th and 17th centuries. Using the lusterware technology, one of the finest examples of medieval Islamic use of ceramics as wall decoration can be seen in the Mosque of Uqba also known as the Great Mosque of kairouan (in Tunisia ), the upper part of the mihrab wall is adorned with polychrome and monochrome lusterware tiles; dating from 862 to 863, these tiles were most probably imported from Mesopotamia. Transmitted via Islamic Iberia ,
8556-681: The Middle Ages. The production of lenses has become increasingly proficient, aiding astronomers as well as having other applications in medicine and science. Glass is also employed as the aperture cover in many solar energy collectors. In the 21st century, glass manufacturers have developed different brands of chemically strengthened glass for widespread application in touchscreens for smartphones , tablet computers , and many other types of information appliances . These include Gorilla Glass , developed and manufactured by Corning , AGC Inc. 's Dragontrail and Schott AG 's Xensation. Glass
8680-540: The Pb ion renders it highly immobile and hinders the movement of other ions; lead glasses therefore have high electrical resistance, about two orders of magnitude higher than soda–lime glass (10 vs 10 Ω⋅cm, DC at 250 °C). Aluminosilicate glass typically contains 5–10% alumina (Al 2 O 3 ). Aluminosilicate glass tends to be more difficult to melt and shape compared to borosilicate compositions but has excellent thermal resistance and durability. Aluminosilicate glass
8804-573: The Shang dynasty, in Ancient Roman and Iranian pottery, and Rococo European styles, copying contemporary silverware shapes. A common use of ceramics is for "pots" - containers such as bowls, vases and amphorae , as well as other tableware, but figurines have been very widely made. The earliest evidence of glazed brick is the discovery of glazed bricks in the Elamite Temple at Chogha Zanbil , dated to
8928-677: The UK and around the world. Fine china is not necessarily bone china, and is a term used to refer to ware which does not contain bone ash. China painting, or porcelain painting is the decoration of glazed porcelain objects such as plates, bowls, vases or statues. The body of the object may be hard-paste porcelain , developed in China in the 7th or 8th century, or soft-paste porcelain (often bone china ), developed in 18th-century Europe. The broader term ceramic painting includes painted decoration on lead-glazed earthenware such as creamware or tin-glazed pottery such as maiolica or faience . Typically
9052-485: The UK's Pilkington Brothers, who created a continuous ribbon of glass using a molten tin bath on which the molten glass flows unhindered under the influence of gravity. The top surface of the glass is subjected to nitrogen under pressure to obtain a polished finish. Container glass for common bottles and jars is formed by blowing and pressing methods. This glass is often slightly modified chemically (with more alumina and calcium oxide) for greater water resistance. Once
9176-719: The action of water, making it an ideal material for the manufacture of containers for foodstuffs and most chemicals. Nevertheless, although usually highly resistant to chemical attack, glass will corrode or dissolve under some conditions. The materials that make up a particular glass composition affect how quickly the glass corrodes. Glasses containing a high proportion of alkali or alkaline earth elements are more susceptible to corrosion than other glass compositions. The density of glass varies with chemical composition with values ranging from 2.2 grams per cubic centimetre (2,200 kg/m ) for fused silica to 7.2 grams per cubic centimetre (7,200 kg/m ) for dense flint glass. Glass
9300-538: The beginning of the 11th century and brown-glazed wares have been found in abundance at Khmer sites in northeast Thailand. Decorating pottery with animal forms was a popular style from the 11th to 13th century. Archaeological excavations in the Angkor region have revealed that towards the end of Angkor period production of indigenous pottery declined while there was a dramatic increase in Chinese ceramic imports. Direct evidence of
9424-458: The body is first fired in a kiln to convert it into a hard porous biscuit . Underglaze decoration may then be applied, followed by ceramic glaze , which is fired so it bonds to the body. The glazed porcelain may then be decorated with overglaze painting and fired again at a lower temperature to bond the paint with the glaze. Decoration may be applied by brush or by stenciling , transfer printing , lithography and screen printing . Slipware
9548-411: The cost factor has a low priority. In the laboratory mostly pure chemicals are used. Care must be taken that the raw materials have not reacted with moisture or other chemicals in the environment (such as alkali or alkaline earth metal oxides and hydroxides, or boron oxide ), or that the impurities are quantified (loss on ignition). Evaporation losses during glass melting should be considered during
9672-427: The crystalline ceramic phase can be balanced with the positive CTE of the glassy phase. At a certain point (~70% crystalline) the glass-ceramic has a net CTE near zero. This type of glass-ceramic exhibits excellent mechanical properties and can sustain repeated and quick temperature changes up to 1000 °C. Fibreglass (also called glass fibre reinforced plastic, GRP) is a composite material made by reinforcing
9796-683: The desired form is obtained, glass is usually annealed for the removal of stresses and to increase the glass's hardness and durability. Surface treatments, coatings or lamination may follow to improve the chemical durability ( glass container coatings , glass container internal treatment ), strength ( toughened glass , bulletproof glass , windshields ), or optical properties ( insulated glazing , anti-reflective coating ). New chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because
9920-603: The emperor in 210–209 BCE and whose purpose was to protect the emperor in his afterlife. French sculptor Albert-Ernest Carrier-Belleuse made many terracotta pieces, but possibly the most famous is The Abduction of Hippodameia depicting the Greek mythological scene of a centaur kidnapping Hippodameia on her wedding day. American architect Louis Sullivan is well known for his elaborate glazed terracotta ornamentation, designs that would have been impossible to execute in any other medium. Terracotta and tile were used extensively in
10044-462: The exceptionally clear colourless glass cristallo , so called for its resemblance to natural crystal, which was extensively used for windows, mirrors, ships' lanterns, and lenses. In the 13th, 14th, and 15th centuries, enamelling and gilding on glass vessels were perfected in Egypt and Syria. Towards the end of the 17th century, Bohemia became an important region for glass production, remaining so until
10168-573: The factories of Arita , which had much in common with the Chinese Famille Verte style. The superb quality of its enamel decoration was highly prized in the West and widely imitated by the major European porcelain manufacturers. In 1971 it was declared an important "intangible cultural treasure" by the Japanese government . In the 20th century, interest in the art of the village potter was revived by
10292-427: The fired body is porous. Its uses include vessels (notably flower pots ), water and waste water pipes, bricks, and surface embellishment in building construction . Terracotta has been a common medium for ceramic art ( see below ). Stoneware is a vitreous or semi-vitreous ceramic made primarily from stoneware clay or non- refractory fire clay. Stoneware is fired at high temperatures. Vitrified or not, it
10416-542: The first true porcelain was made in the province of Zhejiang in China during the Eastern Han period. Shards recovered from archaeological Eastern Han kiln sites estimated firing temperature ranged from 1,260 to 1,300 °C (2,300 to 2,370 °F). As far back as 1000 BCE, the so-called "porcelaneous wares" or "proto-porcelain wares" were made using at least some kaolin fired at high temperatures. The dividing line between
10540-454: The first true synthetic glass was made in Lebanon and the coastal north Syria , Mesopotamia or ancient Egypt . The earliest known glass objects, of the mid-third millennium BC, were beads , perhaps initially created as accidental by-products of metalworking ( slags ) or during the production of faience , a pre-glass vitreous material made by a process similar to glazing . Early glass
10664-535: The formation of the mineral mullite within the body at these high temperatures. Properties associated with porcelain include low permeability and elasticity ; considerable strength , hardness , toughness , whiteness , translucency and resonance ; and a high resistance to chemical attack 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,
10788-686: The former Roman Empire in China , the Baltics , the Middle East , and India . The Romans perfected cameo glass , produced by etching and carving through fused layers of different colours to produce a design in relief on the glass object. In post-classical West Africa, Benin was a manufacturer of glass and glass beads. Glass was used extensively in Europe during the Middle Ages . Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. From
10912-555: The glass and melt phases. Important polymer glasses include amorphous and glassy pharmaceutical compounds. These are useful because the solubility of the compound is greatly increased when it is amorphous compared to the same crystalline composition. Many emerging pharmaceuticals are practically insoluble in their crystalline forms. Many polymer thermoplastics familiar to everyday use are glasses. For many applications, like glass bottles or eyewear , polymer glasses ( acrylic glass , polycarbonate or polyethylene terephthalate ) are
11036-493: The glass transition range. The glass transition may be described as analogous to a second-order phase transition where the intensive thermodynamic variables such as the thermal expansivity and heat capacity are discontinuous. However, the equilibrium theory of phase transformations does not hold for glass, and hence the glass transition cannot be classed as one of the classical equilibrium phase transformations in solids. Glass can form naturally from volcanic magma. Obsidian
11160-406: The glass transition temperature is not supported by empirical research or theoretical analysis (see viscosity in solids ). Though atomic motion at glass surfaces can be observed, and viscosity on the order of 10 –10 Pa s can be measured in glass, such a high value reinforces the fact that glass would not change shape appreciably over even large periods of time. For melt quenching, if the cooling
11284-695: The late Eastern Han period (100–200 CE), the Three Kingdoms period (220–280 CE), the Six Dynasties period (220–589 CE), and thereafter. China in particular has had a continuous history of large-scale production, with the Imperial factories usually producing the best work. The Tang dynasty (618 to 906 CE) is especially noted for grave goods figures of humans, animals and model houses, boats and other goods, excavated (usually illegally) from graves in large numbers. Some experts believe
11408-458: The liquid can easily be supercooled into a glass. Examples include LiCl: R H 2 O (a solution of lithium chloride salt and water molecules) in the composition range 4< R <8. sugar glass , or Ca 0.4 K 0.6 (NO 3 ) 1.4 . Glass electrolytes in the form of Ba-doped Li-glass and Ba-doped Na-glass have been proposed as solutions to problems identified with organic liquid electrolytes used in modern lithium-ion battery cells. Following
11532-611: The material, e.g. "glass" , " glasses ", " magnifying glass ". Glass is most often formed by rapid cooling ( quenching ) of the molten form. Some glasses such as volcanic glass are naturally occurring, and obsidian has been used to make arrowheads and knives since the Stone Age . Archaeological evidence suggests glassmaking dates back to at least 3600 BC in Mesopotamia , Egypt , or Syria . The earliest known glass objects were beads , perhaps created accidentally during metalworking or
11656-605: The material, the skills of the individual maker, attention to utility, and an absence of excessive decoration that was typical to the Victorian era. The word "ceramics" comes from the Greek keramikos (κεραμεικός), meaning "pottery", which in turn comes from keramos (κέραμος) meaning "potter's clay". Most traditional ceramic products were made from clay (or clay mixed with other materials), shaped and subjected to heat, and tableware and decorative ceramics are generally still made this way. In modern ceramic engineering usage, ceramics
11780-481: The melt whilst it floats on a gas stream) or splat quenching (pressing the melt between two metal anvils or rollers), may be used to increase the cooling rate or to reduce crystal nucleation triggers. In the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. Amorphous metal wires have been produced by sputtering molten metal onto
11904-433: The melt. The high density of lead glass (silica + lead oxide (PbO) + potassium oxide (K 2 O) + soda (Na 2 O) + zinc oxide (ZnO) + alumina) results in a high electron density, and hence high refractive index, making the look of glassware more brilliant and causing noticeably more specular reflection and increased optical dispersion . Lead glass has a high elasticity, making the glassware more workable and giving rise to
12028-619: The melting temperature and simplify glass processing. Sodium carbonate (Na 2 CO 3 , "soda") is a common additive and acts to lower the glass-transition temperature. However, sodium silicate is water-soluble , so lime (CaO, calcium oxide , generally obtained from limestone ), along with magnesium oxide (MgO), and aluminium oxide (Al 2 O 3 ), are commonly added to improve chemical durability. Soda–lime glasses (Na 2 O) + lime (CaO) + magnesia (MgO) + alumina (Al 2 O 3 ) account for over 75% of manufactured glass, containing about 70 to 74% silica by weight. Soda–lime–silicate glass
12152-410: The metallic ions will absorb wavelengths of light corresponding to specific colours. In the manufacturing process, glasses can be poured, formed, extruded and moulded into forms ranging from flat sheets to highly intricate shapes. The finished product is brittle but can be laminated or tempered to enhance durability. Glass is typically inert, resistant to chemical attack, and can mostly withstand
12276-506: The modern Western cultures. There is evidence that pottery was independently invented in several regions of the world, including East Asia, Sub-Saharan Africa, the Near East, and the Americas. Although pottery figurines are found from earlier periods in Europe, the oldest pottery vessels come from East Asia, with finds in China and Japan, then still linked by a land bridge, and some in what is now
12400-409: The most significant architectural innovations of modern times, where glass buildings now often dominate the skylines of many modern cities . These systems use stainless steel fittings countersunk into recesses in the corners of the glass panels allowing strengthened panes to appear unsupported creating a flush exterior. Structural glazing systems have their roots in iron and glass conservatories of
12524-535: The old capital of Kyoto , the Raku family continued to produce the rough tea bowls that had so delighted connoisseurs. At Mino , potters continued to reconstruct the classic formulas of Momoyama-era Seto-type tea wares of Mino, such as Oribe ware . By the 1990s many master potters worked away from ancient kilns and made classic wares in all parts of Japan. Korean pottery has had a continuous tradition since simple earthenware from about 8000 BCE. Styles have generally been
12648-652: The pottery fragments had scorch marks, suggesting that the pottery was used for cooking. Many remarkable containers were made from stone before the invention of pottery in Western Asia (which occurred around 7,000 BC), and before the invention of agriculture . The Natufian culture created elegant stone mortars during the period between 12,000 and 9,500 BC. Around 8000 BC, several early settlements became experts in crafting beautiful and highly sophisticated containers from stone, using materials such as alabaster or granite , and employing sand to shape and polish. Artisans used
12772-539: The prehistoric period. Most of the pottery, however, dates to the pre-Angkorian period and consists mainly of pinkish terracotta pots which were either hand-made or thrown on a wheel, and then decorated with incised patterns. Glazed wares first appear in the archaeological record at the end of the 9th century at the Roluos temple group in the Angkor region, where green-glazed pot shards have been found. A brown glaze became popular at
12896-922: The production of faience , which is a form of pottery using lead glazes. Due to its ease of formability into any shape, glass has been traditionally used for vessels, such as bowls , vases , bottles , jars and drinking glasses. Soda–lime glass , containing around 70% silica , accounts for around 90% of modern manufactured glass. Glass can be coloured by adding metal salts or painted and printed with vitreous enamels , leading to its use in stained glass windows and other glass art objects. The refractive , reflective and transmission properties of glass make glass suitable for manufacturing optical lenses , prisms , and optoelectronics materials. Extruded glass fibres have applications as optical fibres in communications networks, thermal insulating material when matted as glass wool to trap air, or in glass-fibre reinforced plastic ( fibreglass ). The standard definition of
13020-529: The production to the European Union market. The other big factory in the town is Metarem, which makes farming transport machinery. There's also a cardboard factory. The town had one of the biggest companies in North Bulgaria for seeds, and a smaller factory for sweets and larger company for animal feed. Pavlikeni is twinned with: This Veliko Tarnovo Province , Bulgaria location article
13144-424: The selection of the raw materials, e.g., sodium selenite may be preferred over easily evaporating selenium dioxide (SeO 2 ). Also, more readily reacting raw materials may be preferred over relatively inert ones, such as aluminium hydroxide (Al(OH) 3 ) over alumina (Al 2 O 3 ). Usually, the melts are carried out in platinum crucibles to reduce contamination from the crucible material. Glass homogeneity
13268-456: The shapes of vessels is provided by scenes depicted on bas-reliefs at Khmer temples, which also offer insight into domestic and ritualistic uses of the wares. The wide range of utilitarian shapes suggest the Khmers used ceramics in their daily life for cooking, food preservation, carrying and storing liquids, as containers for medicinal herbs, perfumes and cosmetics. There is Chinese porcelain from
13392-516: The small, almost mosaic, brightly coloured zellige tiles of Morocco . With exceptions, notably the Porcelain Tower of Nanjing , tiles or glazed bricks do not feature largely in East Asian ceramics. Although pottery figurines are found from earlier periods in Europe, the oldest pottery vessels come from East Asia, with finds in China and Japan, then still linked by a land bridge, and some in what
13516-587: The start of the 20th century. By the 17th century, glass in the Venetian tradition was also being produced in England . In about 1675, George Ravenscroft invented lead crystal glass, with cut glass becoming fashionable in the 18th century. Ornamental glass objects became an important art medium during the Art Nouveau period in the late 19th century. Throughout the 20th century, new mass production techniques led to
13640-469: The strength of glass. Carefully drawn flawless glass fibres can be produced with a strength of up to 11.5 gigapascals (1,670,000 psi). The observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. This assumption
13764-460: The system Al-Fe-Si may undergo a first-order transition to an amorphous form (dubbed "q-glass") on rapid cooling from the melt. Transmission electron microscopy (TEM) images indicate that q-glass nucleates from the melt as discrete particles with uniform spherical growth in all directions. While x-ray diffraction reveals the isotropic nature of q-glass, a nucleation barrier exists implying an interfacial discontinuity (or internal surface) between
13888-524: 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". Bone china is a type of soft-paste porcelain that is composed of bone ash , feldspathic material , and kaolin . It has been defined as ware with a translucent body containing a minimum of 30% of phosphate derived from animal bone and calculated calcium phosphate. Developed by English potter Josiah Spode , bone china
14012-417: The town buildings of Victorian Birmingham , England. There is a long history of ceramic art in almost all developed cultures, and often ceramic objects are all the artistic evidence left from vanished cultures, like that of the Nok in Africa over 3,000 years ago. Cultures especially noted for ceramics include the Chinese , Cretan , Greek , Persian , Mayan , Japanese , and Korean cultures, as well as
14136-521: The two and true porcelain wares is not a clear one. Archaeological finds have pushed the dates to as early as the Han dynasty (206–BCE – 220 CE). The Imperial porcelain of the Song dynasty (960–1279), featuring very subtle decoration shallowly carved by knife in the clay, is regarded by many authorities as the peak of Chinese ceramics , though the large and more exuberantly painted ceramics of
14260-500: The veins in the material to maximize visual effect. Such object have been found in abundance on the upper Euphrates river , in what is today eastern Syria, especially at the site of Bouqras . These form the early stages of the development of the Art of Mesopotamia . Early pots were made by what is known as the "coiling" method, which worked the clay into a long string that wound to form a shape that later made smooth walls. The potter's wheel
14384-512: The walls entirely covered in porcelain. Surviving examples include ones at Capodimonte , Naples, the Royal Palace of Madrid and the nearby Royal Palace of Aranjuez . Elaborate cocklestoves were a feature of rooms of the middle and upper-classes in Northern Europe from the 17th to 19th centuries. There are several other types of traditional tiles that remain in manufacture, for example,
14508-451: The widespread availability of glass in much larger amounts, making it practical as a building material and enabling new applications of glass. In the 1920s a mould -etch process was developed, in which art was etched directly into the mould so that each cast piece emerged from the mould with the image already on the surface of the glass. This reduced manufacturing costs and, combined with a wider use of coloured glass, led to cheap glassware in
14632-402: The year 1268. The study found that the room temperature viscosity of this glass was roughly 10 Pa · s which is about 10 times less viscous than a previous estimate made in 1998, which focused on soda-lime silicate glass. Even with this lower viscosity, the study authors calculated that the maximum flow rate of medieval glass is 1 nm per billion years, making it impossible to observe in
14756-461: Was almost exclusively an English product, with production being effectively localised in Stoke-on-Trent . Most major English firms made or still make it, including Mintons , Coalport , Spode , Royal Crown Derby , Royal Doulton , Wedgwood and Worcester . In the UK, references to "china" or "porcelain" can refer to bone china, and "English porcelain" has been used as a term for it, both in
14880-509: Was developed by the Islamic potters, the first examples found as blue-painted ware in Basra , dating from about the 8th century. The Islamic world had contact with China, and increasingly adapted many Chinese decorative motifs. Persian wares gradually relaxed Islamic restrictions on figurative ornament, and painted figuratives scenes became very important. Stoneware was also an important craft in Islamic pottery, produced throughout Iraq and Syria by
15004-510: Was originally used in the United Kingdom and United States during World War II to manufacture radomes . Uses of fibreglass include building and construction materials, boat hulls, car body parts, and aerospace composite materials. Glass-fibre wool is an excellent thermal and sound insulation material, commonly used in buildings (e.g. attic and cavity wall insulation ), and plumbing (e.g. pipe insulation ), and soundproofing . It
15128-575: Was probably invented in Mesopotamia by the 4th millennium BCE, but spread across nearly all Eurasia and much of Africa, though it remained unknown in the New World until the arrival of Europeans. Decoration of the clay by incising and painting is found very widely, and was initially geometric, but often included figurative designs from very early on. So important is pottery to the archaeology of prehistoric cultures that many are known by names taken from their distinctive, and often very fine, pottery, such as
15252-539: Was rarely transparent and often contained impurities and imperfections, and is technically faience rather than true glass, which did not appear until the 15th century BC. However, red-orange glass beads excavated from the Indus Valley Civilization dated before 1700 BC (possibly as early as 1900 BC) predate sustained glass production, which appeared around 1600 BC in Mesopotamia and 1500 BC in Egypt. During
15376-423: Was used as funerary jars, storage jars and kitchen pots up to the 17th century. Some of the kilns improved their methods and are known as the “Six Old Kilns”. From the 11th to the 16th century, Japan imported much porcelain from China and some from Korea. The Japanese overlord Toyotomi Hideyoshi 's attempts to conquer China in the 1590s were dubbed the "Ceramic Wars"; the emigration of Korean potters appeared to be
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