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83-463: 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

166-462: A National Institute for Occupational Safety and Health approved respirator with replaceable cartridges and dust filters; using a local exhaust ventilation system or working outside; using proper lubricants; wearing protective clothing; showering and shampooing immediately afterward; and using a wet mop to clean the workshop. There are lapidary clubs throughout the world. In Australia, there are numerous gem shows, including an annual gem show called

249-414: 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 continues to make it into the 21st century. The decoration

332-425: A gemcutter is a person who specializes in cutting diamonds, but in older contexts the term refers to artists who produced hardstone carvings ; engraved gems such as jade carvings, a branch of miniature sculpture or ornament in gemstone. By extension, the term lapidary has sometimes been applied to collectors of and dealers in gems, or to anyone who is knowledgeable in precious stones. The etymological root of

415-637: A 13th-century text, stands out for its inclusion of unusual lore about gemstones. William M. Holler notes that the Lapidary of Sydrac cataloged not only conventional healing properties of stones but also fantastical claims, such as stones that could grant invincibility or manipulate human emotions. This text reflects the broader medieval belief in the mystical powers of nature and the importance of lapidaries in transmitting both empirical knowledge and magical traditions. In literary contexts, lapidary traditions also made their way into poetry. Tony Davenport’s analysis of

498-552: A colored background. Stahl's work is known for its refined modelling and the vibrancy of its figures. He thus combined the benefits of jasperware and pâte-sur-pâte . A stand at the World's Fair 1900 in Paris was the first major public presentation of his work and gained him a gold medal. For this event, two huge wall plates were created with dimensions of 220 cm × 60 cm (87 in × 24 in), each. Pottery Pottery

581-517: A continuous lapidary practice. According to Jason Hawkes and Stephanie Wynne-Jones , archaeological evidence suggests that trade in lapidary products between Africa and India was established in the 1st millennium CE. People of the Deccan region of India and those near the coast of East Africa had innovated their own techniques for lapidary before the 10th century, as evidenced by excavations and Indian and non-Indian texts dated to that period. Lapidary

664-400: A differentiated culture which was earlier thought to be typical Indus Valley civilisation (IVC) culture. Pottery is durable, and fragments, at least, often survive long after artifacts made from less-durable materials have decayed past recognition. Combined with other evidence, the study of pottery artefacts is helpful in the development of theories on the organisation, economic condition and

747-402: 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

830-459: A locality. The main ingredient of the body is clay . Some different types used for pottery include: It is common for clays and other raw materials to be mixed to produce clay bodies suited to specific purposes. Various mineral processing techniques are often utilised before mixing the raw materials, with comminution being effectively universal for non-clay materials. Examples of non-clay materials include: The production of pottery includes

913-589: A modern gemcutter's work are the following activities: Cutting of harder stones is done with a diamond-edged saw. For softer materials, a medium other than diamond can be used, such as silicon carbide, garnet , emery, or corundum. Diamond cutting requires the use of diamond tools because of the extreme hardness of diamonds. The cutting, grinding, and polishing operations are usually lubricated with water, oil, or other liquids. Beyond these broader categories, there are other specialized forms of lapidary techniques, such as casting, carving, jewelry, and mosaics . While

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996-416: A more distant connection between groups, such as trade in the same market or even relatively close settlements. Techniques that require more studied replication (i.e., the selection of clay and the fashioning of clay) may indicate a closer connection between peoples, as these methods are usually only transmissible between potters and those otherwise directly involved in production. Such a relationship requires

1079-448: A polish is achieved. In older systems, the grinding and polishing powders were applied separately to the grinding or buffing wheel. Often, the final polish will use a different medium such as tin oxide or cerium(IV) oxide . The initial shaping and facet placement may be done using laps with grits of 220, 600, 1200. The polishing step, however, requires grits of a much higher grade, such as 8,000, 14,000, 50,000 and even 100,000. This grit

1162-581: A rough guide, modern earthenwares are normally fired 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 earthenware can be fired effectively as low as 600 °C (1,112 °F), achievable in primitive pit firing . The time spent at any particular temperature

1245-455: A salt of antimony, and black from iron oxide . Other colours sometimes appear, including white used as the main body colour, with applied reliefs in one of the other colours. The yellow is rare. A few pieces, mostly the larger ones like vases, use several colours together, and some pieces mix jasperware and other types together. The earliest jasper was stained throughout, which is known as "solid," but before long most items were coloured only on

1328-566: A specialized thermal adhesive . The dopstick can be hand-held or inserted into the indexing equipment for more precise faceting. A coolant then needs to be constantly applied to prevent softening of the cement. Diamonds, however, are held mechanically, or with low- melting point tin-lead solder , since the resultant heat generated by friction can be extreme, thus preventing the use of thermal adhesives . Cabochons - smooth-shaped gemstones without facets such as jade or turquoise , and indeed most gemstones - are instead shaped and polished in much

1411-512: A waterproof barrier, and improve its durability. Below are the major types of glazing commonly used in pottery: 1. Glossy Glaze - Produces a shiny, reflective surface. - Highlights intricate patterns and textures. - Often used for decorative purposes. 2. Matte Glaze - Provides a smooth, non-reflective finish. - Suitable for modern and minimalist designs. - Ideal for functional wares like plates and mugs, as it minimizes glare. 3. Transparent Glaze - Can be glossy or matte. - Allows

1494-410: Is a key ingredient. Wedgwood had introduced a different type of stoneware called black basalt a decade earlier. He had been researching a white stoneware for some time, creating a body called "waxen white jasper" by 1773–1774. This tended to fail in firing, and was not as attractive as the final jasperware, and little was sold. Jasperware's composition varies but according to one 19th-century analysis it

1577-449: Is also embedded into a metal lap, but sometimes applied manually to the lap during polishing. Another specialized form of lapidary work is the inlaying of marble and gemstones into a marble matrix. This technique is known in English as pietra dura , for the hardstones that are used, like onyx , jasper and carnelian . In Florence and Naples , where the technique was developed in

1660-401: Is also important, the combination of heat and time is known as heatwork . Kilns can be monitored by pyrometers , thermocouples and pyrometric devices . The atmosphere within a kiln during firing can affect the appearance of the body and glaze. Key to this is the differing colours of the various oxides of iron, such as iron(III) oxide (also known as ferric oxide or Fe 2 O 3 ) which

1743-508: Is another example of a medieval lapidary that reflects the blending of practical and mystical knowledge. As detailed in A Medieval Book of Magical Stones: The Peterborough Lapidary , this text catalogs various gemstones and their magical properties, emphasizing the belief that stones could influence human behavior, protect against harm, and even cure diseases. The Peterborough Lapidary demonstrates how lapidaries were used not only for healing but also for magical and protective purposes, reflecting

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1826-482: Is associated with brown-red colours, whilst iron(II) oxide (also known as ferrous oxide or FeO) is associated with much darker colours, including black. The oxygen concentration in the kiln influences the type, and relative proportions, of these iron oxides in fired the body and glaze: for example, where there is a lack of oxygen during firing the associated carbon monoxide (CO) will readily react with oxygen in Fe 2 O 3 in

1909-503: Is done using a lap , a precision metal plate embedded with grit similar to the more familiar embedding of grit on paper the lap is of high precision particularly for flatness and turned by a motor. The grit material is normally diamond and sometimes corundum for their hardness. Only diamond is hard enough on the Mohs scale to shape and polish a diamond. Faceting requires equipment allowing for very precise adjustment of angle and location around

1992-400: Is important part of archaeology for understanding the archaeological culture of the excavated site by studying the fabric of artifacts, such as their usage, source material composition, decorative pattern, color of patterns, etc. This helps to understand characteristics, sophistication , habits, technology, tools, trade, etc. of the people who made and used the pottery. Carbon dating reveals

2075-426: Is lit and the woman runs around the circumference of the mound touching the burning torch to the dried grass. Some mounds are still being constructed as others are already burning. Pottery may be decorated in many different ways. Some decoration can be done before or after the firing, and may be undertaken before or after glazing. Glaze is a glassy coating on pottery, and reasons to use it include decoration, ensuring

2158-425: Is 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). This is higher than used for the other types, and achieving these temperatures was a long struggle, as well as realizing what materials were needed. The toughness, strength and translucence of porcelain, relative to other types of pottery, arises mainly from vitrification and

2241-633: Is normally fired below 1200 °C. Because unglazed earthenware is porous, it has limited utility for the storage of liquids or as tableware. However, earthenware has had a continuous history from the Neolithic period to today. It can be made from a wide variety of clays, some of which fire to a buff, brown or black colour, with iron in the constituent minerals resulting in a reddish-brown. Reddish coloured varieties are called terracotta , especially when unglazed or used for sculpture. The development of ceramic glaze made impermeable pottery possible, improving

2324-481: Is not always the case; for example fritware uses no or little clay, so falls outside these groups. Historic pottery of all these types is often grouped as either "fine" wares, relatively expensive and well-made, and following the aesthetic taste of the culture concerned, or alternatively "coarse", "popular", "folk" or "village" wares, mostly undecorated, or simply so, and often less well-made. Cooking in pottery became less popular once metal pots became available, but

2407-671: Is one of the oldest human inventions , originating before the Neolithic period , with ceramic objects such as the Gravettian culture Venus of Dolní Věstonice figurine discovered in the Czech Republic dating back to 29,000–25,000 BC. However, the earliest known pottery vessels were discovered in Jiangxi , China, which date back to 18,000 BC. Other early Neolithic and pre-Neolithic pottery artifacts have been found, in Jōmon Japan (10,500 BC),

2490-430: Is placed within the context of linguistic and migratory patterns, it becomes an even more prevalent category of social artifact. As proposed by Olivier P. Gosselain, it is possible to understand ranges of cross-cultural interaction by looking closely at the chaîne opératoire of ceramic production. The methods used to produce pottery in early Sub-Saharan Africa are divisible into three categories: techniques visible to

2573-405: Is shaped by a variety of techniques, which include: Prior to firing, the water in an article needs to be removed. A number of different stages, or conditions of the article, can be identified: Firing produces permanent and irreversible chemical and physical changes in the body. It is only after firing that the article or material is pottery. In lower-fired pottery, the changes include sintering ,

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2656-455: Is still used for dishes that benefit from the qualities of pottery cooking, typically slow cooking in an oven, such as biryani , cassoulet , daube , tagine , jollof rice , kedjenou , cazuela and types of baked beans . The earliest forms of pottery were made from clays that were fired at low temperatures, initially in pit-fires or in open bonfires . They were hand formed and undecorated. Earthenware can be fired as low as 600 °C, and

2739-400: The "clay matrix" – composed of grains of less than 0.02 mm grains which can be seen using the high-powered microscopes or a scanning electron microscope , and the "clay inclusions" – which are larger grains of clay and could be seen with the naked eye or a low-power binocular microscope. For geologists, fabric analysis means spatial arrangement of minerals in a rock. For Archaeologists,

2822-566: The "fabric analysis" of pottery entails the study of clay matrix and inclusions in the clay body as well as the firing temperature and conditions . Analysis is done to examine the following 3 in detail: The Six fabrics of Kalibangan is a good example of fabric analysis. Body , or clay body, is the material used to form pottery. Thus a potter might prepare, or order from a supplier, such an amount of earthenware body, stoneware body or porcelain body. The compositions of clay bodies varies considerably, and include both prepared and 'as dug';

2905-526: The Russian Far East (14,000 BC), Sub-Saharan Africa (9,400 BC), South America (9,000s–7,000s BC), and the Middle East (7,000s–6,000s BC). Pottery is made by forming a clay body into objects of a desired shape and heating them to high temperatures (600–1600 °C) in a bonfire , pit or kiln , which induces reactions that lead to permanent changes including increasing the strength and rigidity of

2988-584: The Shang dynasty . Stones can contain asbestos, silica, lead, talc, and other hazardous ingredients. The dust produced by lapidary techniques on such stones can cause health issues if inhaled. Copper(II) oxide , which is common in colorful minerals such as turquoise and malachite, can damage the endocrine and central nervous systems. The most common minerals are silicates , and the dust from these rocks can result in silicosis . Fossil rocks can be radioactive . For lapidary work, safety precautions include wearing

3071-614: The 16th century, it is called opere di commessi . The Medici Chapel at San Lorenzo in Florence is completely veneered with inlaid hard stones. The specialty of micromosaics , which developed in the late-18th century in Naples and Rome, is sometimes covered under the umbrella term of lapidary work. In this technique, minute slivers of glass are assembled to create still life, cityscape views, and other images. In China , lapidary work specializing in jade carving has been continuous since at least

3154-761: The Elder laid the foundations for later medieval interpretations of gemstones. In his examination of lyngurium —a mythical gemstone described by Theophrastus—Steven A. Walton discusses how classical knowledge was transmitted and adapted in medieval lapidary traditions. Despite the mythical nature of some of these stones, medieval lapidaries continued to draw on classical sources, blending scientific knowledge with magical beliefs. Walton highlights how these texts cataloged stones not only for their aesthetic and material properties but also for their purported magical and medicinal functions, making lapidaries sources essential for texts for both scholars and practitioners of natural philosophy during

3237-555: The GEMBOREE, which is a nationwide lapidary competition. There is a collection of gem and mineral shows held in Tucson, Arizona , at the beginning of February each year. The event began with the Tucson Gem and Mineral Society Show and has now grown to include dozens of other independent shows. In 2012, this concurrent group of shows constituted the largest gem and mineral event in the world. In

3320-565: The Middle Ages emphasizes the medical role lapidaries played, particularly in guiding the use of gemstones for healing. These texts described how different stones, often categorized by color, composition, and astrological associations, could be used to treat specific ailments. Riddle points out that medieval lapidaries were not merely collections of folklore; they were often considered legitimate medical texts, consulted by physicians and healers to guide treatment practices. The Peterborough Lapidary

3403-503: The ability of the involved parties to communicate effectively, implying pre-existing norms of contact or a shared language between the two. Thus, the patterns of technical diffusion in pot-making that are visible via archaeological findings also reveal patterns in societal interaction. Chronologies based on pottery are often essential for dating non-literate cultures and are often of help in the dating of historic cultures as well. Trace-element analysis , mostly by neutron activation , allows

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3486-452: The age. Sites with similar pottery characteristics have the same culture, those sites which have distinct cultural characteristics but with some overlap are indicative of cultural exchange such as trade or living in vicinity or continuity of habitation, etc. Examples are black and red ware , redware , Sothi-Siswal culture and Painted Grey Ware culture . The six fabrics of Kalibangan is a good example of use of fabric analysis in identifying

3569-473: The belief that gemstones could cure illnesses and provide spiritual protection. Kitson argues that lapidaries in this period served a dual purpose: they were not only scientific texts that described natural phenomena but also moral and religious guides that connected material objects to divine forces. Medieval lapidaries were deeply embedded in the practice of lithotherapy, the belief in the healing properties of stones. John M. Riddle’s analysis of lithotherapy in

3652-417: The branches and then grass is piled high to complete the mound. Although the mound contains the pots of many women, who are related through their husbands' extended families, each women is responsible for her own or her immediate family's pots within the mound. When a mound is completed and the ground around has been swept clean of residual combustible material, a senior potter lights the fire. A handful of grass

3735-563: The celebrity of aristocratic amateurs Lady Templeton and Lady Diana Beauclerk , as well as Emma Crewe , no doubt helped sales. Ancient and modern works in various media were copied and new, original designs created. Jasperware is particularly associated with the neoclassical sculptor and designer John Flaxman Jr., who began to supply Wedgwood with designs from 1775. Flaxman mostly worked in wax when designing for Wedgwood. The designs were then cast; some of them are still in production. Sir William Hamilton 's collection of ancient Greek vases

3818-431: The cultural development of the societies that produced or acquired pottery. The study of pottery may also allow inferences to be drawn about a culture's daily life, religion, social relationships, attitudes towards neighbours, attitudes to their own world and even the way the culture understood the universe. It is valuable to look into pottery as an archaeological record of potential interaction between peoples. When pottery

3901-480: The duration of firing influences the final characteristics of the ceramic. Thus, the maximum temperature within a kiln is often held constant for a period of time to soak the wares to produce the maturity required in the body of the wares. Kilns may be heated by burning combustible materials, such as wood , coal and gas , or by electricity . The use of microwave energy has been investigated. When used as fuels, coal and wood can introduce smoke, soot and ash into

3984-562: The end of the 18th century, they made jasperware plaques for a "porcelain room" in the Casita del Príncipe at the Escorial . In the late 19th century, Jean-Baptiste Stahl developed his own style and techniques during his work at Villeroy & Boch in Mettlach, Saar, Germany. The name Phanolith was coined for this kind of jasperware. His work is praised for the translucency of the white porcelain on

4067-460: The eye (decoration, firing and post-firing techniques), techniques related to the materials (selection or processing of clay, etc.), and techniques of molding or fashioning the clay. These three categories can be used to consider the implications of the reoccurrence of a particular sort of pottery in different areas. Generally, the techniques that are easily visible (the first category of those mentioned above) are thus readily imitated, and may indicate

4150-430: The following stages: Before being shaped, clay must be prepared. This may include kneading to ensure an even moisture content throughout the body. Air trapped within the clay body needs to be removed, or de-aired, 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

4233-481: The foot) is left unglazed or, alternatively, special refractory " spurs " are used as supports. These are removed and discarded after the firing. Some specialised glazing techniques include: Types of Glazing in Pottery. Glazing in pottery is the process of applying a coating or layer of material to ceramics that, when fired, forms a vitreous or glass-like surface. Glazes enhance the aesthetic appeal of pottery, provide

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4316-880: The form of drilling stone and rock. The earliest roots of drilling rocks date back to approximately one million years ago. The early Egyptians developed cutting and jewelry fashioning methods for lapis lazuli , turquoise , and amethyst . The art of lapidary was relatively well-developed in the Indian subcontinent by the early 1st millennium CE. The surviving manuscripts of the 3rd century Buddhist text Rathanpariksha by Buddha Bhatta, and several Hindu texts of mid-1st millennium CE such as Agni Purana and Agastimata , are Sanskrit treatises on lapidary arts. They discuss sources of gems and diamonds, their origins, qualities, testing, cutting and polishing, and making jewelry from them. Several other Sanskrit texts on gems and lapidary arts have been dated to post-10th century, suggesting

4399-646: The formation of the mineral mullite within the body at these high temperatures. Although porcelain was first made in China , the Chinese traditionally do not recognise it as a distinct category, grouping it with stoneware as "high-fired" ware, opposed to "low-fired" earthenware. This confuses the issue of when it was first made. A degree of translucency and whiteness was achieved by the Tang dynasty (AD 618–906), and considerable quantities were being exported. The modern level of whiteness

4482-443: The former being by far the dominant type for studio and industry. The properties also vary considerably, and include plasticity and mechanical strength before firing; the firing temperature needed to mature them; properties after firing, such as permeability, mechanical strength and colour. There can be regional variations in the properties of raw materials used for pottery, and these can lead to wares that are unique in character to

4565-412: The fusing together of coarser particles in the body at their points of contact with each other. In the case of porcelain, where higher firing-temperatures are used, the physical, chemical and mineralogical properties of the constituents in the body are greatly altered. In all cases, the reason for firing is to permanently harden the wares, and the firing regime must be appropriate to the materials used. As

4648-418: The gemstone for facet-placement, a process sometimes referred to as indexing. The design may be computer-generated or left up to the skill and expertise of the individual cutting the gemstone. During the process of grinding, faceting, and lapping, the gemstone is usually affixed ("dopped") to a rod (frequently referred to as a "dop" or "dopstick") made of wood, or perhaps brass or steel, with dopping cement ,

4731-404: The gemstone in the rough state may be trimmed to remove undesirable material or to separate it on a cleavage line with a diamond bladed saw, accurately described as cutting and once done by the use of a chisel or similar tool to simply break off pieces that were usable as single gemstones, the actual shaping and polishing of a gemstone is a grinding or sanding process. This grinding and sanding

4814-518: The glaze. Lapidary Lapidary (from the Latin lapidarius ) is the practice of shaping stone , minerals , or gemstones into decorative items such as cabochons , engraved gems (including cameos ), and faceted designs. A person who practices lapidary is known as a lapidarist . A lapidarist uses the lapidary techniques of cutting, grinding, and polishing. Hardstone carving requires specialized carving techniques. In modern contexts,

4897-451: The idea that stones had sacred meanings, offering protection and spiritual benefits to those who used them correctly. Beinert suggests that these texts served as “windows on a medieval world” where natural objects were seen as manifestations of divine power, bridging the gap between the material and the spiritual. Several notable examples of medieval lapidaries highlight their widespread use and cultural significance. The Lapidary of Sydrac ,

4980-417: The item is impermeable to liquids, and minimizing the adherence of pollutants. Glaze may be applied by spraying, dipping, trailing or brushing on an aqueous suspension of the unfired glaze. The colour of a glaze after it has been fired may be significantly different from before firing. To prevent glazed wares sticking to kiln furniture during firing, either a small part of the object being fired (for example,

5063-431: The kiln which can affect the appearance of unprotected wares. For this reason, wares fired in wood- or coal-fired kilns are often placed in the kiln in saggars , ceramic boxes, to protect them. Modern kilns fuelled by gas or electricity are cleaner and more easily controlled than older wood- or coal-fired kilns and often allow shorter firing times to be used. Niche techniques include: [...] pots are positioned on and amid

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5146-576: The late Middle Ages, as European kilns were less efficient, and the right type of clay less common. It remained a speciality of Germany until the Renaissance. Stoneware is very tough and practical, and much of it has always been utilitarian, for the kitchen or storage rather than the table. But "fine" stoneware has been important in China , Japan and the West, and continues to be made. Many utilitarian types have also come to be appreciated as art. Porcelain

5229-433: The medieval period. In Anglo-Saxon England, lapidaries became particularly significant as both medical and religious guides. Peter Kitson traces the transmission of lapidary knowledge into early medieval England, emphasizing how these texts informed by Lapidaries functioned as practical manuals for physicians, clergy, and scholars. The Old English Lapidary , for instance, detailed the healing properties of stones, reflecting

5312-586: The medieval poem Pearl reveals how the symbolic meanings of gemstones, as described in lapidaries, informed the poem’s themes of loss, beauty, and spiritual transcendence. Davenport suggests that the portrayal of jewels in Pearl draws on lapidary traditions to convey deeper religious and moral messages, illustrating how lapidary knowledge permeated not only scientific and medical texts but also literary and artistic works. There are three broad categories of lapidary arts: tumbling , cabochon cutting , and faceting . Among

5395-499: The medieval understanding that the natural world was imbued with supernatural power. Lapidaries also played an important role in medieval spirituality. Richard A. Beinert’s analysis of medieval piety and lapidary literature emphasizes how these texts reflected religious beliefs. Medieval Christians often associated gemstones with biblical figures, virtues, and divine forces. Lapidaries like the Peterborough Lapidary reinforced

5478-424: The object. Much pottery is purely utilitarian, but some can also be regarded as ceramic art . An article can be decorated before or after firing. Pottery is traditionally divided into three types: earthenware , stoneware and porcelain . All three may be glazed and unglazed. All may also be decorated by various techniques. In many examples the group a piece belongs to is immediately visually apparent, but this

5561-502: The popularity and practicality of pottery vessels. Decoration has evolved and developed through history. Stoneware is pottery that has been fired in a kiln at a relatively high temperature, from about 1,100 °C to 1,200 °C, and is stronger and non-porous to liquids. The Chinese, who developed stoneware very early on, classify this together with porcelain as high-fired wares. In contrast, stoneware could only be produced in Europe from

5644-588: The powers believed to be held by some stones - as believed in medieval Europe. The beliefs about the powers of stones included their ability to prevent harm, heal ailments, or offer health benefits. Lapidary appeared as an English adjective in the 18th century. The earliest known lapidary work likely occurred during the Stone Age . As people created tools from stone, they realized that some geological materials were harder than others. The next earliest documented examples of what could be considered lapidary arts came in

5727-421: The raw materials and cause it to be reduced to FeO. An oxygen deficient condition, called a reducing atmosphere, is generated by preventing the complete combustion of the kiln fuel; this is achieved by deliberately restricting the supply of air or by supplying an excess of fuel. Firing pottery can be done using a variety of methods, with a kiln being the usual firing method. Both the maximum temperature and

5810-410: The same manner. They are usually left up to the skill and expertise of the individual cutting the gemstone and to similar equipment such as the lapping equipment. Most modern lapidary work is done using motorized equipment. Polishing is done with resin- or metal-bonded emery , silicon carbide (carborundum), aluminium oxide ( corundum ), or diamond dust in successively decreasing particle sizes until

5893-485: The solid light blue. In the best early pieces the relief work was gone over, including some undercutting, by lapidaries . The artists used for jasperware cannot always be identified, as they are not named on pieces they designed. Wedgwood commissioned George Stubbs and William Wood, as well as the Flaxmans, father and son. William Hackwood was his chief in-house modeller, who was sometimes allowed to initial pieces. Using

5976-467: The sources of clay to be accurately identified and the thermoluminescence test can be used to provide an estimate of the date of last firing. Examining sherds from prehistory, scientists learned that during high-temperature firing, iron materials in clay record the state of the Earth's magnetic field at that moment. The "clay body" is also called the "paste" or the "fabric" , which consists of 2 things,

6059-463: The surface; these are known as "dipped" or "dip". Dipping was first used in 1777, Wedgwood writing that "the Cobalt @ 36 s. per lb, which being too dear to mix with the clay of the whole grounds". By 1829 production in jasper had virtually ceased, but in 1844 production resumed making dipped wares. Solid jasper was not manufactured again until 1860. Early dark blue was often made by dipping a body made from

6142-569: The underlying decoration or texture of the pottery to show through. - Often used over underglaze decorations. 4. Opaque Glaze - Completely covers the surface of the pottery, hiding any underlying texture or decoration. - Useful for creating uniform, bold colors. 5. Celadon Glaze - A translucent glaze, usually in shades of green or blue. - Originated in China and is popular in East Asian ceramics. - Accentuates carved or textured designs beneath

6225-543: The vase in black and white jasperware, which was finally completed in 1790, the figures perhaps modelled by William Hackwood. The replica was exhibited in London in that year, with the initial showing restricted to 1,900 tickets, which soon sold out. Wedgwood's careful copies proved extremely useful when the vase was smashed in the British Museum in 1845, and then reconstructed by the restorer John Doubleday . The original edition

6308-578: The word lapidary is the Latin word lapis , meaning "stone". In the 14th century, the term evolved from lapidarius , meaning 'stonecutter' or 'working with stone', into the Old French word lapidaire , meaning 'one skilled in working with precious stones'. In French , and later English , the term is also used for a lapidary text , which was a treatise on precious stones that details their appearance, formation, and properties - particularly in terms of

6391-420: Was also a significant tradition in early Mesoamerica . The lapidary products were used as status symbols, for offerings, and during burials. They were made from shell , jade , turquoise , and greenstones . Aztec lapidarists used string saws and drills made of reed and bone as their lapidary tools. The history of lapidaries can be traced back to the classical world, where writers like Theophrastus and Pliny

6474-606: Was an important influence on Flaxman's work. These vases were first known in England from D'Hancarville 's engravings, published in stages from 1766. Inspiration for Flaxman and Wedgwood came not only from ancient ceramics, but also from cameo glass , particularly the Portland Vase which was brought to England by Hamilton by 1784. The vase was lent to Wedgwood by William Cavendish-Bentinck, 3rd Duke of Portland from 1786. Wedgwood devoted four years of painstaking attempts at duplicating

6557-581: Was approximately: 57% barium sulphate , 29% ball clay , 10% flint, 4% barium carbonate . Barium sulphate ("cawk" or "heavy-spar") was a fluxing agent and obtainable as a by-product of lead mining in nearby Derbyshire . The fired body is naturally white but usually stained with metallic oxide colors; its most common shade is pale blue, but dark blue, lilac, sage green (described as "sea-green" by Wedgwood), black, and yellow are also used, with sage green due to chromium oxide , blue to cobalt oxide , and lilac to manganese oxide , with yellow probably coming from

6640-435: 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

6723-450: 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. Named after the mineral jasper for marketing reasons, the exact Wedgwood formula remains confidential, but analyses indicate that barium sulphate

6806-512: Was not reached until much later, in the 14th century. Porcelain was also made in Korea and in Japan from the end of the 16th century, after suitable kaolin was located in those countries. It was not made effectively outside East Asia until the 18th century. The study of pottery can help to provide an insight into past cultures. Fabric analysis (see section below), used to analyse the fabric of pottery ,

6889-502: Was of 50 copies; in 1838 a further edition was cast in one piece, with the background then painted. Wedgwood jasperware can often be dated by the style of potter's marks , although there are exceptions to the rules: Jasperware was widely copied in England and elsewhere from its introduction, especially by other makers of Staffordshire pottery . The Real Fabrica del Buen Retiro in Madrid produced jasperware effects in biscuit porcelain . At

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