Proto-celadon was a type of Chinese ceramic which developed during the Shang period and Western Han periods. It is described as "proto-porcelain", was glazed in light yellowish green; the body of proto-celadon was high-fired, the Chinese classification including porcelain, with an iron content below 3%. Firing temperature was around 1200 degrees Celsius. In Western terms the wares are stoneware. Surface treatment consisted of a lime glaze; the shapes manufactured in proto-celadon were similar to the objects manufactured in bronze. During the Shang and Zhou periods, proto-celadon was produced in the areas south of the Yangtze river. Following this period, production improved in quantity and quality. From the Eastern Han period, true celadon ware started to appear, with production focused in Zhejiang Province. Although still following the shapes and patterns of proto-celadon wares, these advances now represented the characteristics of porcelain, with refined clays and appropriate firing temperatures.
These advances were followed by those of Yue ware, the blooming of celadon production from the period of the Song dynasty. A Handbook of Chinese Ceramics from The Metropolitan Museum of Art
French porcelain has a history spanning a period from the 17th century to the present. The French were involved in the early European efforts to discover the secrets of making the hard-paste porcelain known from Chinese and Japanese export porcelain, they succeeded in developing soft-paste porcelain, but Meissen porcelain was the first to make true hard-paste, around 1710, the French took over 50 years to catch up with Meissen and the other German factories. But by the 1760s, kaolin had been discovered near Limoges, the relocated royal-owned Sèvres factory took the lead in European porcelain design as rococo turned into what is broadly known as the Louis XVI style and the Empire style. French styles were soon being imitated in porcelain in Germany, as far afield as Russia, they were imitated in the cheaper French faience, this and other materials elsewhere. This dominance lasted until at least 1830. Before the French Revolution in 1789, French production was complicated by various royal patents and monopolies restricting the production of various types of wares, which could sometimes be circumvented by obtaining the "protection" of a member of the royal family or senior courtier.
Throughout the 18th and 19th centuries, France had a vigorous faience industry, making high-quality tin-glazed earthenware that remained in touch with artistic fashion. At least before 1800, this catered to the lower end of the market successfully, so that porcelain factories concentrated on the top end, in France and elsewhere. Compared to other European countries, French manufacturers have concentrated on tablewares and decorative vessels rather than figures, with Mennecy-Villeroy porcelain being something of an exception. Where figures and groups were produced, these were most in the French invention of unglazed biscuit porcelain. Chinese porcelain had long been imported from China, was a expensive and desired luxury. Chinese porcelains were treasured, collected from the time of Francis I, sometimes adorned with elaborate mountings of precious metal to protect them and enhance their beauty. Huge amounts of silver were sent from Europe to China to pay for the desired Chinese porcelain wares, numerous attempts were made to duplicate the material.
It was at the Nevers manufactory that Chinese-style blue and white wares were produced for the first time in France, with production running between 1650 and 1680. Chinese styles would be taken up by factories in Normandy following the foundation of the French East India Company in 1664; the first soft-paste porcelain in France was developed in an effort to imitate high-valued Chinese hard-paste porcelain, follow the attempts of Medici porcelain in the 16th century. The first soft-paste frit porcelain, was produced at the Rouen manufactory in 1673, in order to mimic "la véritable porcelaine de Chine", became known as "Porcelaine française"; the technique of producing the new material was discovered by the Rouen potter Louis Poterat. Dr. Martin Lister reported from his voyage to Paris, printed in 1698, that a manufacture of porcelain "as white and translucid as the one that came from the East" was in full operation at Saint-Cloud; the French lexicographer Jacques Savary des Brûlons wrote in 1722 about these first experiments in his Dictionnaire universel du commerce: Fifteen or twenty years ago an attempt was made in France to copy Chinese porcelain: the first attempts made in Rouen were quite successful... these faience objects from new factories are not ranked as French faience – this is the genuine porcelain invented by the French during the last few years and manufactured successively in Rouen, Passy near Paris, in Saint Cloud.
Colbert set up the Royal Factory of Saint-Cloud in 1664 in order to make copies of "Indian-style" porcelain. Saint-Cloud became a important manufactory for the new wares. However, once French manufacturers discovered how to produce a much wider range of colours in porcelain by the 1730s, using overglaze "enamel" decoration, they abandoned underglaze blue more and than those of other European countries - some English factories continued to make a significant proportion of blue and white wares until the end of the century and beyond. Louis XIV had received 1,500 pieces of porcelain from the Siamese Embassy to France in 1686, but the manufacturing secret had remained elusive. France discovered the Chinese technique of hard-paste porcelain through the efforts of the Jesuit Father François Xavier d'Entrecolles between 1712 and 1722; the letters sent to Father Orry in Paris were first published by Jean-Baptiste Du Halde in 1735, with English editions appearing in 1736 or 1738. The letters were again published by Abbé Jean-Baptiste Grosier in his General Description of China.
D'Entrecolles sent material specimens to Europe, which were analysed by Réaumur, led to the establishment of the Sèvres Manufactory once equivalent materials were found in Europe. After 1730, polychrome porcelain came to be produced in imitation of Chinese polychrome styles of porcelain, such as the "Famille rose" types; the Japanese Kakiemon style of Arita porcelain, known as "Fleurs indiennes" was used as an inspiration in Saint-Cloud porcelain and Chantilly porcelain. A patent granted to the Chantilly factory in 1735 by Louis XV describes the right to make porcelain façon de Japon ("in imitatio
Ding ware, Ting ware or Dingyao were Chinese ceramics porcelain, produced in the prefecture of Dingzhou in Hebei in northern China. The main kilns were at Jianci in Quyang County, they were produced between the Tang and Yuan dynasties of imperial China, though their finest period was in the 11th century, under the Northern Song. The kilns "were in constant operation from the early eighth until the mid-fourteenth century."The most characteristic wares are thin porcelains with a white or greyish body and a nearly transparent white-tinted glaze, though they are classed as stoneware by some. Chemical analysis has shown that they were made of a kaolinitic clay without any petuntse or "porcelain stone", they are decorated, with uncoloured designs that are incised or in shallow relief. Ding ware was the most famous northern Chinese white ware under the Song, although there was increasing competition from the Qingbai ware from Jingdezhen in the south, which by the end of the Song had eclipsed Ding ware, achieving a predominance it has maintained in subsequent centuries.
A key event in this process was the flight of the remaining Northern Song court to the south, after they lost control of the north in the disastrous Jin-Song wars of the 1120s. A new Southern Song court was based in Hangzhou; this may have been accompanied by the movement of potters to Jingdezhen. The white glaze was noted for a slight ivory tint, apart from which it was transparent. Earlier, pre-Song, pieces had a blueish tint as they were fired with wood, producing a reducing atmosphere. A change to firing with coal in the 10th century, produced the tint described as "ivory". Other "secondary" wares had monochrome glazes in different colours: a rare black, various shades of red and brown and green; these "are better known through literature than through surviving examples... only the red and black are represented by entire pieces". These may lack any other decoration. Song court taste valued plain wares decorated only by exquisite monochrome glazes in colours that were difficult to achieve, such as the famous Ru ware, produced for only 40 years, with surviving pieces totalling a two-figure number.
Another rare group is white with painted underglaze decoration in a brown derived from iron oxides. Pieces produced in Ding ware were open vessels of a small size, with shapes and decoration borrowed from metalwork, as in the bowls with lobed rims. Vases are uncommon. Pieces were thrown on the potter's wheel with templates, but in the late 11th century moulds began to be used, which included the inside decoration carved or incised with a knife on the leather-hard piece. Any decoration on the outside of pieces continued to be hand-carved for some time. While the decoration was hand-carved, it was scrolling plant-forms including lotus and peony, with some simple animals such as ducks and fish; these were "generally rather open and well spaced, executed with remarkable fluency and an unfailing sense of compositional balance". Moulds allowed more complexity, including scenes with children and other animals; the firing process was with bowls placed upside down in the kiln, which meant that the glaze had to be wiped from the rim, which left a rough rim, many pieces were given a thin metal rim in silver or a "brassy alloy".
The Ding kilns developed stepped saggars, allowing several bowls reducing in size, to be fired in the same saggar, increasing the efficiency of kiln loading. Traditional East Asian thinking only classifies pottery into earthenware and porcelain, without the intermediate European class of stoneware, the many local types of stoneware such as Ding ware were classed as porcelain, though not white and translucent. Terms such as "porcellaneous" or "near-porcelain" may be used in such cases; the range and output of the wares was large, producing ceramics of high quality for the wealthy merchant class and the scholar-literati class, as well as tributary ceramics of the highest quality for the imperial court. A chronicle records that "the king went to pay his respects at the Zongde Dian and offered up 2,000 pieces of Ding ware decorated with gold", but other records suggest that the rough rims and "teardrops" formed by running glaze meant that they were not considered fine enough for use by the emperor himself, or at least had become so regarded by the late Southern Song.
Ding ware was grouped as one of the Five Famous Kilns. It influenced the early white wares of Jingdezhen, where the white porcelain preceding Qingbai ware is known as "Southern Ding", Qingbai shows considerable influence in its decoration. Ding production continued under non-Chinese interlopers from Manchuria. Jin court taste was different from the Song, favouring elegant plant-scroll designs, now moulded, which were more intricate than those produced under the Northern Song. There was renewed borrowing from T'ang decoration in silver and stone, from metalware shapes, such as lobed or notched rims to bowls and plates; the increased complexity in scrolling plant designs was significant for the history of Chinese pottery. Osborne, The Oxford Companion to the Decorative Arts, 1975, OUP, ISBN 0198661134 Rawson, Chinese Ornament: The Lotus and the Dragon, 1984, British Museum Publications, ISBN 0714114316 Vainker, S. J. Chinese Pottery and Porcelain, 1991, British Muse
Frankenthal is a town in southwestern Germany, in the state of Rhineland-Palatinate. Frankenthal was first mentioned in 772. In 1119 an Augustinian monastery was built here, the ruins of which — known, after the founder, as the Erkenbertruine — still stand today in the town centre. In the second half of the 16th century, people from Flanders, persecuted for their religious beliefs, settled in Frankenthal, they brought economic prosperity to the town. Some of them were important carpet weavers and artists whose Frankenthaler Malerschule acquired some fame. In 1577 the settlement was raised to the status of a town by the Count Palatine Johann Casimir. In 1600 Frankenthal was converted to a fortress. In 1621 it was besieged by the Spanish during the Thirty Years' War, successively occupied by troops of the opposing sides. Trade and industry were ruined and the town was not reconstructed until 1682. In 1689 the town was burnt to the ground by French troops in the War of the Grand Alliance; the town did not recover from this for more than fifty years.
However, in 1750, under the rule of the Elector Charles Theodore, Frankenthal was established as a centre of industry. Numerous factories were opened and mulberry trees were planted for silk production. In 1755 the famous Frankenthal porcelain factory was opened, which remained in production until 1800. In 1797 the town came under French occupation during the French Revolutionary Wars, it passed into the rule of Bavaria in 1816. The beginning of modern industrialisation is dated from 1859. In 1938 the Jewish synagogue, built in 1884, was burnt to the ground during the Kristallnacht. In 1943 during a bombing raid the centre of the town was completely destroyed. In 1945, at the end of World War II, its industries in ruins, it was occupied first by the Americans and by the French. From 1946 Frankenthal has been part of the federal state of Rhineland-Palatinate. Today the town is again the site of some medium-sized industries. 1850: 4.767 1900: 16.899 2000: around 50.000 2015: 48.363 Frankenthal is twinned with: Colombes, France since October 26, 1958 Strausberg, Germany since October 16, 1990 Sopot, Poland since April 17, 1991Partnership: Community of Butamwa, Rwanda since December 15, 1982Associated towns: Berlin-Neukölln, Germany Pushkin, Russia Blumenau, Brazil Abraham Heidanus, a reformed theologian Esther Moscherosch née Ackermann, wife of the statesman and baroque poet Johann Michael Moscherosch Jacob Marrel, still life painter Johann Philipp Becker, revolutionary Georg Vierling, composer Konrad Maurer, a Bavarian legal historian Julius von Michel, ophthalmologist Richard Reverdy, civil engineer Karl Wendling and music pedagogue Karl Perron, opera singer Franz Nissl and psychiatrist August von Parseval, designer of airships Hermann Wilker, rower Oskar Perron, mathematician Ludwig Marum and politician, victims of the Holocaust Arnold Fanck and pioneer of the mountain film Paul Martini, medical doctor Carl Neubronner, politician Georg Gehring, wrestler Karl Huber and trade unionist Josef Frank, politician Werner Knab, jurist and SS leader Hans Carste and conductor Adolf Metzner, Leichtathlet Rudi Fischer, Football goalkeeper The family name "Frankenthal" is attested among people scattered in many countries - among Jews - and indicates an ultimate origin of the family in the town, though it might be centuries old and leaving no memory other than the name.
"Frankenthal". Encyclopædia Britannica. 1911. "Frankenthal". Collier's New Encyclopedia. 1921
Maastricht is a city and a municipality in the southeast of the Netherlands. It is largest city of the province of Limburg. Maastricht is located at the point where the Jeker joins it, it is adjacent to the border with Belgium. Maastricht developed from a Roman settlement to a medieval religious centre. In the 16th century it in the 19th century an early industrial city. Today, the city is a thriving regional hub, it became well-known as the birthplace of the Euro. Maastricht has 1677 national heritage buildings, the second highest number in the Netherlands, after Amsterdam; the city is popular with tourists for shopping and recreation, has a large international student population. Maastricht is a member of the Most Ancient European Towns Network and is part of the Meuse-Rhine Euroregion, which includes the nearby German and Belgian cities of Aachen, Hasselt, Liège, Tongeren; the Meuse-Rhine Euroregion is a metropolis with a population of about 3.9 million with several international universities.
Maastricht is mentioned in ancient documents as Treiectinsem ab. 575, Treiectensis in 634, Triectu in 7th century, Triiect in 768-781, Traiecto in 945, Masetrieth in 1051. The place name Maastricht is an Old Dutch compound Masa- + Old Dutch *treiekt, itself borrowed from Gallo-Romance *TRAECTU cf. its Walloon name li trek, from Classical Latin trajectus with the addition of Maas "Meuse" to avoid the confusion with the -trecht of Utrecht having the same original form and etymology. The Latin name first appears in medieval documents and it is not known whether *Trajectu was Maastricht's name during Roman times. A resident of Maastricht is referred to as Maastrichtenaar whilst in the local dialect it is either Mestreechteneer or, Sjeng. Neanderthal remains have been found to the west of Maastricht. Of a date are Palaeolithic remains, between 8,000 and 25,000 years old. Celts lived here around 500 BC, at a spot where the river Meuse was shallow and therefore easy to cross, it is not known when the Romans arrived in Maastricht, or whether the settlement was founded by them.
The Romans built a bridge across the Meuse in the 1st century AD, during the reign of Augustus Caesar. The bridge was an important link in the main road between Cologne. Roman Maastricht was relatively small. Remains of the Roman road, the bridge, a religious shrine, a Roman bath, a granary, some houses and the 4th-century castrum walls and gates, have been excavated. Fragments of provincial Roman sculptures, as well as coins, glass and other objects from Roman Maastricht are on display in the exhibition space of the city's public library. According to legend, the Armenian-born Saint Servatius, Bishop of Tongeren, died in Maastricht in 384 where he was interred along the Roman road, outside the castrum. According to Gregory of Tours bishop Monulph was to have built around 570 the first stone church on the grave of Servatius, the present-day Basilica of Saint Servatius; the city remained an early Christian diocese until it lost the distinction to nearby Liège in the 8th or 9th century. In the early Middle Ages Maastricht was part of the heartland of the Carolingian Empire along with Aachen and the area around Liège.
The town was an important centre for manufacturing. Merovingian coins minted in Maastricht have been found in places throughout Europe. In 881 the town was plundered by the Vikings. In the 10th century it became the capital of the duchy of Lower Lorraine. During the 12th century the town flourished culturally; the provosts of the church of Saint Servatius held important positions in the Holy Roman Empire during this era. The two collegiate churches were rebuilt and redecorated. Maastricht Romanesque stone sculpture and silversmithing are regarded as highlights of Mosan art. Maastricht painters were praised by Wolfram von Eschenbach in his Parzival. Around the same time, the poet Henric van Veldeke wrote a legend of Saint Servatius, one of the earliest works in Dutch literature; the two main churches acquired a wealth of relics and the septennial Maastricht Pilgrimage became a major event. Unlike most Dutch towns, Maastricht did not receive city rights at a certain date; these developed during its long history.
In 1204 the city's dual authority was formalised in a treaty, with the prince-bishops of Liège and the dukes of Brabant holding joint sovereignty over the city. Soon afterwards the first ring of medieval walls were built. In 1275, the old Roman bridge collapsed under the weight of a procession. A replacement, funded by church indulgences, was built to the north and survives until today, the Sint Servaasbrug. Throughout the Middle Ages, the city remained a centre for trade and manufacturing principally of wool and leather but economic decline set in. After a brief period of economic prosperity around 1500, the city's economy suffered during the wars of religion of the 16th and 17th centuries, recovery did not happen until the industrial revolution in the early 19th century; the important strategic location of Maastricht resulted in the construction of an impressive array of fortifications around the city during this period. The Spanish and Dutch garrisons became an important factor in the city's economy.
In 1579 the city was sacked by the Spanish army led by
Cologne is the largest city of Germany's most populous federal state of North Rhine-Westphalia, its 1 million+ inhabitants make it the fourth most populous city in Germany after Berlin and Munich. The largest city on the Rhine, it is the most populous city both of the Rhine-Ruhr Metropolitan Region, Germany's largest and one of Europe's major metropolitan areas, of the Rhineland. Centred on the left bank of the Rhine, Cologne is about 45 kilometres southeast of North Rhine-Westphalia's capital of Düsseldorf and 25 kilometres northwest of Bonn, it is the largest city in the Central Ripuarian dialect areas. The city's famous Cologne Cathedral is the seat of the Catholic Archbishop of Cologne. There are many institutions of higher education in the city, most notably the University of Cologne, one of Europe's oldest and largest universities, the Technical University of Cologne, Germany's largest university of applied sciences, the German Sport University Cologne, Germany's only sport university.
Cologne Bonn Airport lies in the southeast of the city. The main airport for the Rhine-Ruhr region is Düsseldorf Airport. Cologne was founded and established in Ubii territory in the 1st century AD as the Roman Colonia Claudia Ara Agrippinensium, the first word of, the origin of its name. An alternative Latin name of the settlement is Augusta Ubiorum, after the Ubii. "Cologne", the French version of the city's name, has become standard in English as well. The city functioned as the capital of the Roman province of Germania Inferior and as the headquarters of the Roman military in the region until occupied by the Franks in 462. During the Middle Ages it flourished on one of the most important major trade routes between east and west in Europe. Cologne was one of the leading members of the Hanseatic League and one of the largest cities north of the Alps in medieval and Renaissance times. Prior to World War II the city had undergone several occupations by the French and by the British. Cologne was one of the most bombed cities in Germany during World War II, with the Royal Air Force dropping 34,711 long tons of bombs on the city.
The bombing reduced the population by 95% due to evacuation, destroyed the entire city. With the intention of restoring as many historic buildings as possible, the successful postwar rebuilding has resulted in a mixed and unique cityscape. Cologne is a major cultural centre for the Rhineland. Exhibitions range from local ancient Roman archeological sites to contemporary graphics and sculpture; the Cologne Trade Fair hosts a number of trade shows such as Art Cologne, imm Cologne and the Photokina. The first urban settlement on the grounds of modern-day Cologne was Oppidum Ubiorum, founded in 38 BC by the Ubii, a Cisrhenian Germanic tribe. In 50 AD, the Romans founded Colonia Claudia Ara Agrippinensium on the river Rhine and the city became the provincial capital of Germania Inferior in 85 AD. Considerable Roman remains can be found in present-day Cologne near the wharf area, where a 1,900-year-old Roman boat was discovered in late 2007. From 260 to 271 Cologne was the capital of the Gallic Empire under Postumus and Victorinus.
In 310 under emperor Constantine I a bridge was built over the Rhine at Cologne. Roman imperial governors resided in the city and it became one of the most important trade and production centres in the Roman Empire north of the Alps. Cologne is shown on the 4th century Peutinger Map. Maternus, elected as bishop in 313, was the first known bishop of Cologne; the city was the capital of a Roman province until it was occupied by the Ripuarian Franks in 462. Parts of the original Roman sewers are preserved underneath the city, with the new sewerage system having opened in 1890. Early medieval Cologne was part of Austrasia within the Frankish Empire. In 716, Charles Martel commanded an army for the first time and suffered the only defeat of his life when Chilperic II, King of Neustria, invaded Austrasia and the city fell to him in the Battle of Cologne. Charles fled to the Eifel mountains, rallied supporters, took the city back that same year after defeating Chilperic in the Battle of Amblève. Cologne had been the seat of a bishop since the Roman period.
In 843, Cologne became a city within the Treaty of Verdun-created East Francia. In 953, the archbishops of Cologne first gained noteworthy secular power, when bishop Bruno was appointed as duke by his brother Otto I, King of Germany. In order to weaken the secular nobility, who threatened his power, Otto endowed Bruno and his successors on the bishop's see with the prerogatives of secular princes, thus establishing the Electorate of Cologne, formed by the temporal possessions of the archbishopric and included in the end a strip of territory along the left Bank of the Rhine east of Jülich, as well as the Duchy of Westphalia on the other side of the Rhine, beyond Berg and Mark. By the end of the 12th century, the Archbishop of Cologne was one of the seven electors of the Holy Roman Emperor. Besides being prince elector, he was Arch-chancellor of Italy as well, technically from 1238 and permanently from 1263 until 1803. Following the Battle of Worringen in 1288, Cologne gained its independence from the archbishops and became a Free City.
Archbishop Sigfried II von Westerburg was forced to reside in Bonn. The archbishop preserv
Celadon is a term for pottery denoting both wares glazed in the jade green celadon color known as greenware and a type of transparent glaze with small cracks, first used on greenware, but used on other porcelains. Celadon originated in China, though the term is purely European, notable kilns such as the Longquan kiln in Zhejiang province are renowned for their celadon glazes. Celadon production spread to other regions in Asia, such as Japan and Thailand. European potteries produced some pieces, but it was never a major element there. Finer pieces are in porcelain, but both the color and the glaze can be produced in stoneware and earthenware. Most of the earlier Longquan celadon is on the border of stoneware and porcelain, meeting the Chinese but not the European definitions of porcelain. For many centuries, celadon wares were regarded by the Chinese Imperial court, before being replaced in fashion by painted wares the new blue and white porcelain under the Yuan dynasty; the similarity of the color to jade, traditionally the most valued material in China, was a large part of its attraction.
Celadon continued to be produced in China at a lower level with a conscious sense of reviving older styles. In Korea the celadons produced under the Goryeo Dynasty are regarded as the classic wares of Korean porcelain; the celadon colour is classically produced by firing a glaze containing a little iron oxide at a high temperature in a reducing kiln. The materials must be refined. Too little iron oxide causes a blue colour, too much gives olive and black; the presence of other chemicals may have effects. Pieces made with a celadon glaze are themselves referred to as "celadons." The term "celadon" for the pottery's pale jade-green glaze was coined by European connoisseurs of the wares. One theory is that the term first appeared in France in the 17th century and that it is named after the shepherd Celadon in Honoré d'Urfé's French pastoral romance, L'Astrée, who wore pale green ribbons. Another theory is that the term is a corruption of the name of Saladin, the Ayyubid Sultan, who in 1171 sent forty pieces of the ceramic to Nur ad-Din Zengi, Sultan of Syria.
Yet a third theory is that the word derives from the Sanskrit sila and dhara, which mean "green" and "stone" respectively. Celadon glaze refers to a family of partly transparent but coloured glazes, many with pronounced "crackle", or tiny cracks in the glaze produced in a wide variety of colors used on stoneware or porcelain pottery bodies. So-called "true celadon", which requires a minimum 1,260 °C furnace temperature, a preferred range of 1,285 to 1,305 °C, firing in a reducing atmosphere, originated at the beginning of the Northern Song Dynasty, at least on one strict definition; the unique grey or green celadon glaze is a result of iron oxide's transformation from ferric to ferrous iron during the firing process. Individual pieces in a single firing can have different colours, from small variations in conditions in different parts of the kiln. Most of the time, green was the desired colour, reminding the Chinese of jade, always the most valued material in Chinese culture. Celadon glazes can be produced in a variety of colors, including white, grey and yellow, depending on several factors: the thickness of the applied glaze, the type of clay to which it is applied, the exact chemical makeup of the glaze, the firing temperature the degree of reduction in the kiln atmosphere and the degree of opacity in the glaze.
The most famous and desired shades range from a pale green to deep intense green meaning to mimic the green shades of jade. The main color effect is produced by iron oxide in the glaze clay body. Celadons are exclusively fired in a reducing atmosphere kiln as the chemical changes in the iron oxide which accompany depriving it of free oxygen are what produce the desired colors; as with most glazes, crazing can occur in the glaze and, if the characteristic is desirable, is referred to as "crackle" glaze. Greenwares are found in earthenware from the Shang dynasty onwards. Archaeologist Wang Zhongshu states that shards with a celadon ceramic glaze have been recovered from Eastern Han Dynasty tomb excavations in Zhejiang, that this type of ceramic became well known during the Three Kingdoms; these are now called proto-celadons, tend to browns and yellows, without much green. The earliest major type of celadon was Yue ware, succeeded by a number of kilns in north China producing wares known as Northern Celadons, sometimes used by the imperial court.
The best known of these is Yaozhou ware. All these types were widely exported to the rest of East Asia and the Islamic world. Longquan celadon wares, were first made during the Northern Song, but flourished under the Southern Song, as the capital moved to the south and the northern kilns declined; this had bluish, blue-green, olive green glazes and the bodies had high silica and alkali contents which resembled porcelain wares made at Jingdezhen and Dehua rather than stonewares. All the wares mentioned above were in, or aiming to be in, some shade of green. Other wares which can be classified as celadons, were more in shades of pale blue highly valued by the Chinese, or various browns and off-whites; these were