Stoneware is a rather broad term for pottery or other ceramics fired at a relatively high temperature. A modern technical definition is a vitreous or semi-vitreous ceramic made primarily from stoneware clay or non-refractory fire clay. Whether vitrified or not, it is nonporous (does not soak up liquids); it may or may not be glazed. Historically, across the world, it has been developed after earthenware and before porcelain, and has often been used for high-quality as well as utilitarian wares.
As a rough guide, modern earthenwares are normally fired in a kiln at temperatures in the range of about 1,000°C (1,830 °F) to 1,200 °C (2,190 °F); stonewares at between about 1,100 °C (2,010 °F) to 1,300 °C (2,370 °F); and porcelains at between about 1,200 °C (2,190 °F) to 1,400 °C (2,550 °F). Historically, reaching high temperatures was a long-lasting challenge, and temperatures somewhat below these were used for a long time. Earthenware can be fired effectively as low as 600°C, achievable in primitive pit firing, but 800 °C (1,470 °F) to 1,100 °C (2,010 °F) was more typical. Stoneware also needs certain types of clays, more specific than those able to make earthenware, but can be made from a much wider range than porcelain.
Stoneware is not recognised as a category in traditional East Asian terminology, and much Asian stoneware, such as Chinese Ding ware for example, is counted as porcelain by local definitions. Terms such as "porcellaneous" or "near-porcelain" may be used in such cases. One definition of stoneware is from the Combined Nomenclature of the European Communities, a European industry standard. It states:
In industrial ceramics, five basic categories of stoneware have been suggested:
The key raw material in stoneware is either naturally occurring stoneware clay or non-refractory fire clay. The mineral kaolinite is present but disordered, and although mica and quartz are present their particle size is very small. Stoneware clay is often accompanied by impurities such as iron or carbon, giving it a "dirty" look, and its plasticity can vary widely. Non-refractory fire clay may be another key raw material. Fire clays are generally considered refractory, because they withstand very high temperatures before melting or crumbling. Refractory fire clays have a high concentration of kaolinite, with lesser amounts of mica and quartz. Non-refractory fire clays, however, have larger amounts of mica and feldspar.
Formulations for stoneware vary considerably, although the vast majority will conform to: plastic fire clays, 0 to 100 percent; ball clays, 0 to 15 percent; quartz, 0 to 30 percent; feldspar and chamotte, 0 to 15 percent.
Stoneware can be once-fired or twice-fired. Maximum firing temperatures can vary significantly, from 1100 °C to 1300 °C depending on the flux content. Typically, temperatures will be between 1180 °C and 1280 °C, the higher end of which equate to Bullers Rings 38 to 40 or Seger cones 4 to 8. To produce a better quality fired glaze finish, twice-firing can be used. This can be especially important for formulations composed of highly carbonaceous clays. For these, biscuit firing is around 900 °C, and glost firing (the firing used to form the glaze over the ware) 1180–1280 °C. Water absorption of stoneware products is less than 1 percent.
Another type, Flintless Stoneware, has also been identified. It is defined in the UK Pottery (Health and Welfare) Special Regulations of 1950 as: "Stoneware, the body of which consists of natural clay to which no flint or quartz or other form of free silica has been added."
Traditional East Asian thinking classifies pottery only into "low-fired" and "high-fired" wares, equating to earthenware and porcelain, without the intermediate European class of stoneware, and the many local types of stoneware were mostly classed as porcelain, though often not white and translucent.
Methods of forming stoneware bodies include moulding, slipcasting and wheel throwing. Underglaze and overglaze decoration of many types can be used. Much tableware in stoneware is white-glazed and decorated, and it is then visually highly similar to porcelain or faience earthenware.
The Indus Valley Civilization produced stoneware, with an industry of a nearly industrial-scale mass-production of stoneware bangles throughout the civilization's Mature Period (2600–1900 BC). Early examples of stoneware have been found in China, naturally as an extension of higher temperatures achieved from early development of reduction firing, with large quantities produced from the Han dynasty onwards.
In both medieval China and Japan, stoneware was very common, and several types became admired for their simple forms and subtle glaze effects. Japan did not make porcelain until about 1600, and north China (in contrast to the south) lacks the appropriate kaolin-rich clays for porcelain on a strict Western definition. Jian ware in the Song dynasty was mostly used for tea wares, and appealed to Buddhist monks. Most Longquan celadon, a very important ware in medieval China, was stoneware. Ding ware comes very close to porcelain, and even modern Western sources are notably divided as to how to describe it, although it is not translucent and the body often grey rather than white.
In China, fine pottery was very largely porcelain by the Ming dynasty, and stoneware mostly restricted to utilitarian wares, and those for the poor. Exceptions to this include the unglazed Yixing clay teapot, made from a clay believed to suit tea especially well, and Shiwan ware, used for popular figures and architectural sculpture.
But in Japan many traditional types of stoneware, for example Oribe ware and Shino ware, were preferred for chawan cups for the Japanese tea ceremony, and have been valued up to the present for this and other uses. From a combination of philosophical and nationalist reasons, the primitive or folk art aesthetic qualities of many Japanese village traditions, originally mostly made by farmers in slack periods in the agricultural calendar, have retained considerable prestige. Influential tea masters praised the rough, spontaneous, wabi-sabi, appearance of Japanese rural wares, mostly stoneware, over the perfection of Chinese-inspired porcelain made by highly-skilled specialists.
Stoneware was also produced in Korean pottery, from at least the 5th century, and much of the finest Korean pottery might be so classified; as in China, the border with porcelain is rather fuzzy. Not only celadons but much underglaze blue and white pottery can be called stoneware. Thailand manufactured stoneware in two principal kiln centres, Si Satchanalai and Sukhothai. The firing technology used in Thailand seems to have come from China.
In contrast to Asia, stoneware could be produced in Europe only from the late Middle Ages, as European kilns were less efficient, and the right sorts of clay less common. Some ancient Roman pottery had approached being stoneware, but not as a consistent type of ware. Medieval stoneware remained a much-exported speciality of Germany, especially along the Rhine, until the Renaissance or later, typically used for large jugs, jars and beer-mugs. "Proto-stoneware", such as Pingsdorf ware, and then "near-stoneware" was developed there by 1250, and fully vitrified wares were being produced on a large scale by 1325. The salt-glazed style that became typical was not perfected until the late 15th century.
England was to become the most inventive and important European maker of fancy stoneware in the 18th and 19th centuries, but there is no clear evidence for native production before the mid-17th century. German imports were common from the early 16th century at least, and known as "Cologne ware" after the centre of shipping it, rather than making it. Some German potters were probably making it in London in the 1640s, and a father and son Wooltus (or Woolters) were doing so in Southampton in the 1660s.
Many modern commercial glazed tablewares and kitchenwares use stoneware rather than porcelain or bone china, and it is common in craft and studio pottery. The popular Japanese-inspired raku ware is normally stoneware.
Notable historical European types include:
A Bartmann jug (from German Bartmann, "bearded man"), also called Bellarmine jug, is a type of decorated salt-glazed stoneware that was manufactured in Europe throughout the 16th and 17th centuries, especially in the Cologne region in what is today western Germany. The signature decorative detail was a bearded face mask appearing on the lower neck of the vessel.
They were made as jugs, bottles and pitchers in various sizes and for a multitude of uses, including storage of food or drink, decanting wine and transporting goods.Beer stein
Beer stein ( STYNE), or simply stein, is an English neologism for either traditional beer mugs made out of stoneware, or specifically ornamental beer mugs that are usually sold as souvenirs or collectibles. In German, the word Stein means stone and is not used to refer to a beverage container.
Such Steins may be made out of stoneware, pewter, porcelain, or even silver, wood or crystal glass; they may have open tops or hinged pewter lids with a thumb-lever. Steins usually come in sizes of a half litre or a full litre (or comparable historic sizes). Like decorative tankards, they are often decorated in a nostalgic manner, but with allusions to Germany or Bavaria. It is believed by some that the lid was implemented during the age of the Black Plague, to prevent diseased flies from getting into the beer.Betschdorf
Betschdorf is a commune in the Bas-Rhin department in Grand Est in northeastern France.
It is located about 45 km north-northeast of Strasbourg on the northern edge of the Forêt de Haguenau, the largest undivided forest in France. Betschdorf is a center of craft pottery manufacture, especially salt-glazed stoneware.Bone china
Bone china is a type of 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. Bone china is the strongest of the porcelain or china ceramics, having very high mechanical and physical strength and chip resistance, and is known for its high levels of whiteness and translucency. 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.In the mid-18th century, English potters had not succeeded in making hard-paste porcelain (as made in East Asia and Meissen porcelain) but found bone ash a useful addition to their soft-paste porcelain mixtures, giving strength. This became standard at the Bow porcelain factory in London (operating from around 1747), and spread to some other English factories. The modern product was developed by the Staffordshire potter Josiah Spode in the early 1790s. Spode included kaolin, so his formula, sometimes called "Staffordshire bone-porcelain", was effectively hard-paste, but stronger, and versions were adopted by all the major English factories by around 1815.From its initial development and up to the latter part of the 20th century, bone china 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 Fortnum & Mason, 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 the UK and around the world.Celadon
Celadon is a term for pottery denoting both wares glazed in the jade green celadon color, also known as greenware (the term specialists now tend to use) and a type of transparent glaze, often with small cracks, that was first used on greenware, but later used on other porcelains. Celadon originated in China, though the term is purely European, and notable kilns such as the Longquan kiln in Zhejiang province are renowned for their celadon glazes. Celadon production later spread to other regions in Asia, such as Japan, Korea and Thailand. Eventually, 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 highly regarded by the Chinese Imperial court, before being replaced in fashion by painted wares, especially the new blue and white porcelain under the Yuan dynasty. The similarity of the color to jade, traditionally the most highly valued material in China, was a large part of its attraction. Celadon continued to be produced in China at a lower level, often with a conscious sense of reviving older styles. In Korea the celadons produced under the Goryeo Dynasty (918–1392) 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, as other chemicals can alter the color completely. Too little iron oxide causes a blue colour (sometimes a desired effect), and too much gives olive and finally black; the right amount is between 0.75% and 2.5%. The presence of other chemicals may have effects; titanium dioxide gives a yellowish tinge. Pieces made with a celadon glaze are themselves often referred to as "celadons."Ceramic glaze
Ceramic glaze is an impervious layer or coating of a vitreous substance which has been fused to a ceramic body through firing. Glaze can serve to color, decorate or waterproof an item. Glazing renders earthenware vessels suitable for holding liquids, sealing the inherent porosity of unglazed biscuit earthenware. It also gives a tougher surface. Glaze is also used on stoneware and porcelain. In addition to their functionality, glazes can form a variety of surface finishes, including degrees of glossy or matte finish and color. Glazes may also enhance the underlying design or texture either unmodified or inscribed, carved or painted.
Most pottery produced in recent centuries has been glazed, other than pieces in unglazed terracotta, biscuit porcelain or some other types. Tiles are almost always glazed on the surface face, and modern architectural terracotta is very often glazed. Glazed brick is also common. Domestic sanitary ware is invariably glazed, as are many ceramics used in industry, for example ceramic insulators for overhead power lines.
The most important groups of traditional glazes, named after their main ceramic fluxing agent, are:
Lead-glazed earthenware, is shiny and transparent after firing, which needs only about 800 °C (1,470 °F). It has been used for about 2,000 years around the Mediterranean, in Europe, and China. It includes sancai and Victorian majolica.
Tin-glazed pottery, which coats the ware with an opaque white glaze. Known in the Ancient Near East and then important in Islamic pottery, from which it passed to Europe. Includes faience, maiolica, majolica and Delftware.
Salt-glazed ware, mostly European stoneware. It uses ordinary salt.
Ash glaze, important in East Asia, simply made from wood or plant ash, which contains potash and lime.
Feldspathic glazes of porcelain.Modern materials technology has invented new vitreous glazes that do not fall into these traditional categories.Donabe
Donabe (Japanese: 土鍋, literally "earthenware pot") are pots made out of a special clay for use over an open flame in Japanese cuisine, and in the case of semi-stoneware Banko ware of high petalite content. Often, the food is cooked at the table on a gas burner for various nabemono dishes such as shabu-shabu and dishes served simmering including nabeyaki udon. They are sized by sun, one of the Japanese units of measurement.
The donabe is usually glazed on the inside and porous on the outside. While the material is similar to earthenware or stoneware, donabe can be used over an open flame as well as in an oven if three precautions are taken. First, the outside of the donabe should be dry before use, as moisture within the clay will expand in the heat and may chip or crack the pot. Secondly, the pot should be heated gradually to reduce the possibility of cracks due to heat stress. Third, the pot should never be left over the flame while empty.
If properly treated, these pots should last for decades and a few special ones have survived for centuries. When a new donabe is obtained, one should let the donabe boil water for hours and dry before using it for cooking. Other sources suggest that the user should simply fill the donabe with water and let it sit overnight. This process should be repeated if the donabe has been unused for a long time.
In old ryoutei of Kyoto, decades-old donabe would be stored and only used for special guests. Young donabe would be used for preparing lunch menus and food for cooks, to age them for this purpose.
Donabe is produced by potters of Banko ware, Iga ware, Shigaraki ware, and Mashiko ware.Earthenware
Earthenware is glazed or unglazed nonvitreous pottery that has normally been fired below 1200°C. Porcelain, bone china and stoneware, all fired at high enough temperatures to vitrify, are the main other important types of pottery.
Earthenware comprisesmost building bricks, nearly all European pottery up to the seventeenth century, most of the wares of Egypt, Persia and the near East; Greek, Roman and Mediterranean, and some of the Chinese; and the fine earthenware which forms the greater part of our tableware today.Pit fired earthenware dates back to as early as 29,000–25,000 BC, and for millennia, only earthenware pottery was made, with stoneware gradually developing some 5,000 years ago, but then apparently disappearing for a few thousand years. Outside East Asia, porcelain was manufactured only from the 18th century AD, and then initially as an expensive luxury.
After it is fired, earthenware is opaque and non-vitreous, soft and capable of being scratched with a knife. The Combined Nomenclature of the European Communities describes it as being made of selected clays sometimes mixed with feldspars and varying amounts of other minerals, and white or light-colored (i.e., slightly greyish, cream, or ivory).Ironstone china
Ironstone china, ironstone ware or most commonly just ironstone, is a type of vitreous pottery first made in the United Kingdom in the early 19th century. It is often classed as earthenware although in appearance and properties it is similar to fine stoneware. It was developed in the 19th century by potters in Staffordshire, England as a cheaper, mass-produced alternative for porcelain.There is no iron in ironstone; its name is derived from its notable strength and durability.
Ironstone in Britain's Staffordshire potteries was closely associated with the company founded by Charles James Mason following his patent of 1813, with the name subsequently becoming generic. The strength of Mason's ironstone body enabled the company to produce ornamental objects of considerable size including vestibule vases 1.5 metres high and mantelpieces assembled from several large sections.Antique ironstone wares are collectable, and in particular items made by Mason's.Jasperware
Jasperware, or jasper ware, is a type of pottery first developed by Josiah Wedgwood in the 1770s. Usually described as stoneware, it has an unglazed matte "biscuit" finish and is produced in a number of different colours, of which the most common and best known is a pale blue that has become known as Wedgwood Blue. Relief decorations in contrasting colours (typically in white but also in other colours) are characteristic of jasperware, giving a cameo effect. The reliefs are produced in moulds and applied to the ware as sprigs.After several years of experiments, Wedgwood began to sell jasperware in the late 1770s, at first as small objects, but from the 1780s adding large vases. It was extremely popular, and after a few years many other potters devised their own versions. Wedgwood continued to make it into the 21st century. The decoration was initially in the fashionable Neoclassical style, which was often used in the following centuries, but it could be made to suit other styles. Wedgwood turned to leading artists outside the usual world of Staffordshire pottery for designs. High-quality portraits, mostly in profile, of leading personalities of the day were a popular type of object, matching the fashion for paper-cut silhouettes. The wares have been made into a great variety of decorative objects, but not typically as tableware or teaware. Three-dimensional figures are normally found only as part of a larger piece, and are typically in white. Teawares are usually glazed on the inside.In the original formulation the mixture of clay and other ingredients is tinted throughout by adding dye (often described as "stained"); later the formed but unfired body was merely covered with a dyed slip, so that only the body near the surface had the colour. These types are known as "solid" and "dipped" (or "Jasper dip") respectively. The undyed body was white when fired, sometimes with a yellowish tinge; cobalt was added to elements that were to stay white.Jian ware
Jian ware or Chien ware (Chinese: 建窯; pinyin: Jiàn yáo; Wade–Giles: Chien-yao) is a type of Chinese pottery originally made in Jianyang, Fujian province. It, and local imitations of it, is known in Japan as Tenmoku (天目). The wares are simple shapes in stoneware, with a strong emphasis on subtle effects in the glazes. In the Song dynasty they achieved a high prestige, especially among Buddhist monks and in relation to tea-drinking. They were also highly valued in Japan, where many of the best examples were collected. Though the ceramic body is light-coloured, the wares, generally small cups for tea, bowls and vases, normally are glazed in dark colours, with special effects such as the "hare's fur" "oil-spot" and "partridge feather" patterns caused randomly as excess iron in the glaze is forced out during firing.Pottery
Pottery is the process of forming vessels and other objects with clay and other ceramic materials, which are fired to give them a hard, durable form. Major types include earthenware, stoneware and porcelain. The place where such wares are made by a potter is also called a pottery (plural "potteries"). The definition of pottery used by the American Society for Testing and Materials (ASTM), is "all fired ceramic wares that contain clay when formed, except technical, structural, and refractory products." A different definition, used within the field of ceramics, is "everything which is not porcelain". In archaeology, especially of ancient and prehistoric periods, "pottery" often means vessels only, and figures etc. of the same material are called "terracottas". Clay as a part of the materials used is required by some definitions.
Pottery is one of the oldest human inventions, originating before the Neolithic period, with ceramic objects like the Gravettian culture Venus of Dolní Věstonice figurine discovered in the Czech Republic dating back to 29,000–25,000 BC, and pottery vessels that were discovered in Jiangxi, China, which date back to 18,000 BC. Early Neolithic pottery artefacts have been found in places such as Jōmon Japan (10,500 BC), the Russian Far East (14,000 BC), Sub-Saharan Africa and South America.
Pottery is made by forming a ceramic (often clay) body into objects of a required shape and heating them to high temperatures in a kiln which removes all the water from the clay, which induces reactions that lead to permanent changes including increasing their strength and hardening and setting their shape. A clay body can be decorated before or after firing; however, prior to some shaping processes, clay must be prepared. Kneading helps to ensure an even moisture content throughout the body. Air trapped within the clay body needs to be removed. This is called de-airing and can be accomplished either by a machine called a vacuum pug or manually by wedging. Wedging can also help produce an even moisture content. Once a clay body has been kneaded and de-aired or wedged, it is shaped by a variety of techniques. After it has been shaped, it is dried and then fired.Salt glaze pottery
Salt-glaze or salt glaze pottery is pottery, usually stoneware, with a glaze of glossy, translucent and slightly orange-peel-like texture which was formed by throwing common salt into the kiln during the higher temperature part of the firing process. Sodium from the salt reacts with silica in the clay body to form a glassy coating of sodium silicate. The glaze may be colourless or may be coloured various shades of brown (from iron oxide), blue (from cobalt oxide), or purple (from manganese oxide).Seto ware
Seto ware (瀬戸焼, Seto-yaki) refers to a type of Japanese pottery, stoneware, and ceramics produced in and around Seto in Aichi Prefecture, Japan. The Japanese term for it, setomono, is also used as a generic term for all pottery. Seto was the location of one of the Six Ancient Kilns of Japan.Shiwan ware
Shiwan ware (Chinese: 石灣窯; pinyin: Shíwān yáo; Cantonese Jyutping: Sek6 waan1 jiu4) is Chinese pottery from kilns located in the Shiwanzhen Subdistrict of the provincial city of Foshan, near Guangzhou, Guangdong. It forms part of a larger group of wares from the coastal region known collectively as "Canton stonewares". The hilly, wooded, area provided slopes for dragon kilns to run up, and fuel for them, and was near major ports.
The area has been producing pottery since the Neolithic, and over 100 kiln-sites have now been excavated, but large-scale production of a variety of wares began under the late Ming dynasty, and continues to the present. The Nanfeng Kiln has been in operation for some 500 years, and is now a popular tourist attraction. Shiwan wares have been in a variety of styles, many for utilitarian purposes. Mostly they are (in Western terms) stoneware. Three types of wares especially associated with Shiwan are roof tiles and architectural ornaments, and from the Qing dynasty onwards, imitations of Jun ware and popular polychrome figurines.Tokoname ware
Tokoname ware (常滑焼, Tokoname-yaki) refers to a type of Japanese pottery, stoneware, and ceramics produced in and around the municipality of Tokoname, Aichi, in central Japan. Tokoname was the location of one of the Six Ancient Kilns of Japan.Yixing ware
Yixing clay (simplified Chinese: 宜兴泥; traditional Chinese: 宜興泥; pinyin: Yíxīng ní; Wade–Giles: I-Hsing ni) is a type of clay from the region near the city of Yixing in Jiangsu Province, China, used in Chinese pottery since the Song dynasty (960–1279) when Yixing clay was first mined around China's Lake Tai. From the 17th century on, Yixing wares were commonly exported to Europe. The finished stoneware, which is used for teaware and other small items, is usually red or brown in color. Also known as zisha (宜興紫砂) ware, they are typically left unglazed and use clays that are very cohesive and can form coils, slabs and most commonly slip casts. These clays can also be formed by throwing. The best known wares made from Yixing clay are Yixing clay teapots, tea pets, and other teaware.Yue ware
Yue ware or Yüeh ware (Chinese: 越(州)窯; pinyin: Yuè(zhōu) yáo; Wade–Giles: Yüeh(-chou) yao) is a type of Chinese ceramics, a felspathic siliceous stoneware, which is characteristically decorated with celadon glazing. Yue ware is also sometimes called (Yuezhou) green porcelain (Chinese: (越州)青瓷; pinyin: (Yuèzhōu) qīngcí) in modern literature, but the term is misleading as it is not really porcelain (on Western definitions) and its shades are not really green. It has been "one of the most successful and influential of all south Chinese ceramics types".The wares covered by the term have been gradually reduced; initially used for a wide range of early celadons with a grey body, it was first made more specific to refer only to wares from north China, and then later only to those from the Tang dynasty onwards, and sometimes to restrict it "to the finest quality wares of the ninth and tenth centuries".Zhoukoudian
Zhoukoudian or Choukoutien (周口店) is a cave system in suburban Fangshan District, Beijing. It has yielded many archaeological discoveries, including one of the first specimens of Homo erectus (Homo erectus pekinensis), dubbed Peking Man, and a fine assemblage of bones of the gigantic hyena Pachycrocuta brevirostris.
Dates of when Peking Man inhabited this site vary greatly: 700,000-200,000 years ago, 670,000-470,000 years ago and no earlier than 530,000 years ago.The Peking Man Site was first discovered by Johan Gunnar Andersson in 1921 and was first excavated by Otto Zdansky in 1921 and 1923 unearthing two human teeth. These were later identified by Davidson Black as belonging to a previously unknown species and extensive excavations followed. Fissures in the limestone containing middle Pleistocene deposits have yielded the remains of about 45 individuals as well as animal remains and stone flake andchopping tools.
The oldest animal remains date from as early as 690,000 years ago and tools from 670,000 years ago while another authority dates the tools found from no earlier than 530,000 years ago. During the Upper Palaeolithic, the site was re-occupied and remains of Homo sapiens and its stone and bone tools have also been recovered from the Upper Cave.
The crater Choukoutien on asteroid 243 Ida was named after the location. The caves are located in Fangshan District, southwest of central Beijing.