Guo Yanyi et al. (1995) have studied the characteristics of these moulds and identified three basic types: (1) the original mould; from which (2) the remoulding mould is copied – also known as a son mould; and (3) a body mould which is taken from an existing decorated pot body. The function of the moulds was also designated: (1) the ‘moulding’ mould, for forming complicated body shapes; (2) moulds for stamping a pattern on the pot – often the same mould as (1); (3) the ‘dressing’ mould to correct/perfect the shape of a damp pottery body.
By studying closely inscriptions on Yaozhou pottery moulds Wang Lanfang (1995) has found that it is possible to show how parts of the production were organised there. The inscribed character ‘guan’ indicates that the pots were objects of tribute and since both ‘guan’ and ‘xin guan’ wares have been excavated from graves belonging to high-ranking people this makes sense. Celadon sherds with the ‘guan’ character inscribed on them have been found in Five Dynasties contexts at Yaozhou, showing that the kilns were involved in producing ware for the imperial tribute system. Although made of white porcelain, two ‘guan’ ware bowls and two dishes were excavated from the tomb of the King of Wei state, who was the son-in-law of Emperor Muzong of Liao and buried in the ninth year of Yingli reign (959) in Chifengdayingzicum. It is not stated whether any of these ‘guan’ or ‘xin guan’ wares have been found in lower status contexts. Nevertheless it is clear that they were definitely used in high status contexts and were produced as part of an imperial tribute system.
Other Five Dynasties wares are inscribed with the ‘Ding jia’ character on the back. Either a surname or a full name are also inscribed, which could either be that of the master potter or of the craftsman himself (Wang Lanfang 1995). During the Tang Dynasty at Yaozhou surnames are inscribed on tools; during the Song Dynasty many of the moulds, especially those decorated with children at play, have a full name inscribed in negative in cursive handwriting on the base. It is suggested that because individual’s names occur on the tools and moulds, that the workshops were run by individuals as opposed to institutions, like local authorities, though clearly they were ‘driven’ by the demand for high status wares. The Five Dynasties moulds inscribed with ‘Ding jia’ probably received an assignment to produce tribute for porcelain and when finished continued to produce ‘popular’ wares. During the Song Dynasty, especially between 1078 and 1106, covering the reigns of Yuanfeng and Chongning, Yaozhou specialised in the production of tribute wares for the imperial house.
During the late Song Dynasty small bowls which all have trumpet mouths, straight inclined walls and a small foot ring with a diameter of c. 9.5 cm were one of the specialised products. These were inscribed with ‘Daguan’ (1107–10), ‘Zhenghe’ (1111–17) and Xining (1068–77). The same is true of other (southern) Song kilns, and is surely not unexpected given that predetermined shapes and decorations were produced with moulds in both the Five Dynasties and the Song Dynasty.
Although the glaze is mainly a transparent olive green colour, some is also yellowish brown. The colours are achieved by a combination of the chemical composition of the glazes, the firing temperatures, the cooling cycle and (changes in) kiln atmosphere. Guo Yenyi and Li Guozhen (1986: Table 2) showed by re-firing experiments that the Yaozhou glazes were fired at temperatures as high as 1300 °C; Yang Zhongtang et al. (1995) have determined the firing temperature to be between 1223 and 1309 °C as reflected in the physical characteristics of relict quartz crystals. Using a laser Raman microprobe Yang Zhongtang et al. (1995: 75) investigated the silicate ‘structural units’ (e.g. monomer and dimer units) present in celadon glazes and used the degree of broken bonds and number of non-bridging oxygens per tetrahedral cation (which tend to increase with temperature) as an aid in the interpretation of firing temperatures, though, given the complex chemical environment involved, the interpretation remained tentative.
Yaozhou celadon glazes are characterised by high silica, aluminia and calcium oxide levels and a low level of total alkali (the oxides of potassium and sodium) with a maximum content of around 5%: c. 65–72% SiO2; 13.6–15.3% A12O3; 5.6–12.6% CaO; 1.6–2.2% MgO; 1.9–3.1% K2O; 0.31–0.6% Na2O; 1.5–1.9% Fe2O3; 0.1–0.37 TiO2; 0.47–0.77% P2O5 (Guo Yenyi and Li Guozhen 1986).
Using ICPAES Li Wenchao et al. (1992) considered the ratio of silica to aluminia molecules in celadon glazes. Figure 4.35 shows a clear correlation between aluminia and silica in the glazes (with a correlation coefficient of 0.88). Some distinction is seen between the compositions of the glazes, indicating that slightly different recipes were used. Most Tang (618–906) glazes are above the straight line; the Five Dynasties and Song below it. The molecular ratio of silica/aluminia progressively increased from Tang to Jin (1115–1234) dynasties, and then decreased in the Yuan Dynasty (1279–1368). The implication here is that the relative amount of aluminia increased; the biggest improvement occurring especially between the Tang and Five Dynasties wares, with a change in the (average) ratio from 7.2 to 8.16 (Zang Zhigang et al. 1995: Table 3). Although all celadons contained calcium oxide the average level appears to fall moving from Tang to Song Dynasty from 15.19% to 10.14% (Zang Zhigang et al.1995: 63, Table 4). One of the compositional differences between southern and northern Song celadons is the higher phosphorus pentoxide levels in southern celadon glazes; the southern glazes are also sometimes bluish green. A larger proportion of crystallites in some south Guan-Ru and Ru-Jun northern Song which are contemporary with Yaozhou glazes can be explained by a longer and slower cooling rate than for Yaozhou glazes. There are, however, many bubbles, some unreacted quartz as well as the 0.02 mm thick layer of anorthic crystals (see Section 4.6.2 above) (Go Yen and Lie Gouge 1986: 157) in Yaozhou celadons.
Figure 4.35 The relative molecular % of aluminium oxide versus silica in celadon glazes of Tang, Five Dynasties, Song, Jin and Yuan periods
(after Zhang Zhigang et al. 1995).
The reflectivity of Tang Dynasty, Five Dynasties and Song Dynasty celadon glazes from Yaozhou was determined (Zhang Zhiang et al. 1995: 64), each in the range of 400–800 mμ. For example, Tang had a bias towards bluish green (Figure 4.36), Five Dynasties ginger yellow (Figure 4.37) and Song olive green. A bluish-green colour has a stronger reducing atmosphere than the ginger yellow colour (i.e. there is a higher proportion of ferrous than ferric ions present). Infrared absorption spectra reveal that ferrous (Fe2+) ions have a strong absorption, but for visible light wavelengths the absorption is weaker making the glaze appear blue. Ferric (Fe3+) ions have a strong absorption spectrum in the ultraviolet area, but in visible light the glaze appears yellowish. Both are dependent on the relative proportions of reducing, as opposed to oxidising, gases in the kiln atmosphere during firing. The typical olive green celadon colour was achieved by a balance of reducing gases somewhere between Tang and Five Dynasties; these findings are supported by an analysis of gas bubbles in the glazes.
Figure 4.36 The percentage reflectance of Tang Yaozhou celadon glazes
(after Zhang Zhigang et al. 1995).
Figure 4.37 The percentage reflectance of Five Dynasties Yaozhou celadon glazes
(after Zhang Zhigang et al 1995).
Investigation of the gas bubbles in the glazes in Yaozhou celadon samples from Tang Dynasty, Five Dynasties and Song Dynasty can help to determine the firing atmosphere at the temperature when the glaze became too viscous for the bubbles to escape. By the time the high-temperature glaze had been heated to the maximum temperature to be used in the firing operation, gases released by breakdown of raw materials in the pottery and glaze would have ceased; the main contribution would have been from the kiln atmosphere itself. The determinations showed that the size of the gas bubbles increased by the time of the Song Dynasty and their density decreased (Yang Zhongtang 1992: Table 1). Chemical analysis of the gas bubbles in the glazes using laser Raman micro-probe analysis was also performed. The results are mixed, mainly because the author was aware that there was a degree of variation in the glaze colours both within a dynastic production period as well as between the periods. The main result is that in all the samples there was a greater proportion of reducing gases (e.g. CO, CH4, H2, H2O) than oxidising gases (e.g. O2, CO2 and SO2). However, overall the lowest proportion of reducing gases was in Tang wares, the Five Dynasties contained the highest and the Song Dynasty material contained an intermediate proportion (i.e. it was weakly reducing). The variation in glaze colours showed that in Tang glazes, the most oxidising atmosphere was responsible for producing greyish (bluish) green and ginger yellow colours; in Five Dynasties the most reducing atmosphere produced olive green and jade green colours; in the northern Song the intermediate atmosphere between Tang and Five Dynasties produced olive green and yellowish green colours.
Yaozhou bodies are characterised by relatively high aluminia and relatively low silica contents; the reverse being true of (southern) Longquan wares. The sedimentary rocks which would have been used to make the Yaozhou wares contained iron and titanium impurities. By examining the different proportions of silica, aluminia and the ‘flux’ component using ‘traditional’ chemical analysis and inductively coupled plasma emission spectroscopy, Zhang Zhigang et al. (1995) found that some differences in compositions were observable for Yaozhou wares of different dynasties. Figure 4.38 shows relative levels of ‘fluxing’ components and silica for body compositions of Yaozhou wares dating to the Tang, Five Dynasties, northern Song, Jin and Yuan dynasties; it also includes results of body analyses for southern (Longquan and Shanghlin lake) bodies. The first thing to note is the compositional distinction between northern and southern wares (indicated by a broken line). The second is that, although northern celadons fall in the same area there is a clear chronological shift in the compositions, and therefore the raw materials used. From among the Yaozhou wares there was a (generally) lower relative level of flux used in some (but not all) northern Song wares, with many of the Five Dynasties wares containing the highest proportion. The Tang products occupy an intermediate position between Five Dynasties and Song wares. There are several exceptions to these generalisations, but a major inference that slightly different combinations of raw materials were used still stands.
Figure 4.38 Relative molecular % of fluxes versus silica in Yaozhou ware of a range of Dynasties
(after Zhang Zhigang et al. 1995).
The material used for moulds is characterised by high levels of silica and aluminia at levels which are indistinguishable from the bodies of Yaozhou celadons (compare Guo Yenyi: Table 1; Yanyi et al. 1995: Table 2). The silica levels in the Song Yaozhou moulds range between 62.5% and 71.62%, and aluminia levels between 20.7% and 32.71%. They also contained very low calcium oxide levels of mainly less than 1% and, as with the pottery, a low total alkali of up to a maximum of 3.6% (Guo Yanyi et al. 1995: Table 2). Yaozhou bodies contain between 65.7% and 72.2% silica and between 20.3–29.8% aluminia. Indeed these compositional similarities carry through for most of the other components, especially levels of magnesia and phosphorus pentoxide. Some variation in levels of calcium oxide in the moulds when compared with the pot bodies (a range of 0.37–1.13 in the moulds compared to 0.2–0.53 in the pot bodies) is unlikely to have affected the properties of the raw materials used; even the levels of iron and titanium are comparable. It is clear that very similar raw materials were used for making the moulds and the pot bodies which is a somewhat unexpected result. Wang Fang and Wang Lanfang (1995: 311) have noted the use of a buffering material which appears as a thin yellow layer on the moulding surface; no more specific identification has yet been carried out. However, Anderson and Guo Yanyi (1995: 100) have noted, during experiments designed to reproduce the process of using celadon moulds, that a good releasing agent could either consist of a layer of dusted ash or a mixture of ash and dry clay. The firing temperature of the moulds is claimed to have been between 1100 °C and 1200 °C (Wang Fang and Wang Lefang 1995: 311), yet this is a similar composition to the pots, so a higher firing temperature is likely.
For moulds with fine decoration the porosity of the moulds is a significant factor. The apparent porosity (the proportion of voids in a material) and water absorption of the moulds have been worked out for celadon material. Guo Yanyi et al. (1986: 322, Table 3) found that the decorated plate and bowl moulds (n = 11) had apparent porosities of 27–35%, whereas the undecorated simple animal moulds (n = 2) had apparent porosities of 14–17%. Greater porosity might enable a better quality mould to result, though ‘excessive’ porosity has been found to prevent a precise impression being made (Zhang Zhigang et al. 1995: 100). In any case, a similar level of porosity for Yaozhou saggers suggests that while fine clays were undoubtedly used to make moulds, they were not necessarily selected/prepared from clearly distinguished special clays.
The opportunity to compare the chemical and mineralogical composition of saggers with the mould and pottery bodies has not, as yet, apparently been fully realised. Li Wenchao et al. (1992) report the average silica and aluminia contents of Yaozhou saggers as 58.25% and 37.24% respectively. As might be expected for a ceramic material which is used for the protection of the pots which it contains, the aluminia level is apparently higher than the maximum level of 32.71% for northern Song Yaozhou wares; the silica level is correspondingly lower. You Enpu (1986) has not published the full chemical analyses of the saggers, nor stated the numbers of analyses involved. The ‘average’ porosity of Yaozhou saggers is similar to that for moulds – 14.59%. When compared to results for Ding saggers, Yaozhou saggers apparently contain on average about 10% higher aluminia levels and can therefore be described as more refractory.
As mentioned in the description of the workshop excavations, deposits of clay were found which, quite reasonably, were labelled as raw materials used for the production of celadons in those kilns; these do not appear to have been scientifically tested. However, Guo Yenyi and Li Guozhen (1986: 159) have carried out chemical analyses of ‘typical’ raw materials from places ‘near Yaozhou kiln sites’. Some clays tested contained a mixture of quartz, mica, feldspar and kaolinite; there are some similarities with the composition of the bodies analysed, but this is not absolute proof that they were used. Work by Guo Yanyi (1987) has suggested that Nichi refractory clay, Chenlu refractory clay, Chenlu limestone and Fuping glaze stone, consisting of silty sand, kaolin, calcite, quartz and feldspar (Li Guozhen and Guan Peiying 1979: 196) could all have been used as Yaozhou glaze raw materials. As with many instances of pottery production, raw materials are often mixed. In ‘The stele of Marquis De Ying’ of the Xining reign (1068–1078) ‘at the beginning the body was made with combined clays’, so, in spite of a range of experiments with clay mixing by Li Guozhen and Guan Peiying (1979) only a best estimate can be determined using clay found in the northern Chinese Central Plain near Yaozhou; as Li Guozhen and Guan Peiying (1979) mention, the range of clays and ‘glaze stones’ in the vicinity of the Yaozhou kilns is very wide indeed.
Turkish Iznik pottery which has been decorated with one of the most exuberant ranges of designs with one of the widest range of glaze colours. Its study raises a number of research questions such as what features of the ceramic technology can be seen as being specifically Iznik in origin and what social, economic or political features of the society may have contributed to its production.
Iznik ware was used in Ottoman Turkey between c. 1480 and 1650; copies were made in the nineteenth century and are still being made today. Both prior to the introduction of Iznik decoration on pottery, and after it, the interiors of the mosques and minarets of Ottoman Turkey were sometimes highly decorated using glazed tiles. One hypothesis is that artisans from Tabriz in Iran, who manufactured tiles before 1480, contributed in some way to the emergence of Iznik pottery. However, before describing Iznik ceramic technology in detail, and discussing some of the other features of fifteenth-century ceramic technology, it is necessary to consider what kinds of ceramic technology may have influenced the emergence of Iznik before the fifteenth century, in order to place the technology of Iznik ceramic bodies into a broad context.
The bodies of ‘Iznik’ ware are a kind of stonepaste, also known as ‘fritware’. Stonepaste is a ware which consists of crushed silica combined with a small amount of clay and crushed glass (Henderson 1989b; Tite 1989). It is debatable whether frit, the partially fused primary raw materials of glass-making (see Section 3.3), was in fact added to the silica and clay instead of ground up glass. Whichever was used, it led to the formation of a glass network in the pottery body as it was fired. When the pottery body was fired in the kiln the glass (or frit which was transformed into glass), and the small amount of clay fused together producing the glassy network which extended between some of the quartz crystals. Hence the name of the fabric: stonepaste.
A recent consideration of the origins of stonepaste technology has suggested that some of the earliest wares resulted, not in tandem with the ninth-century development of high lead tin-glazed wares (see Section 4.3.5.1 ), but that, slightly later, Iraqi potters working in the tenth- and eleventh-century court of Fatimid, Egypt, introduced proto-stonepaste wares (Mason and Tite 1994: 88). It is thought that in these contexts the practice of adding quartz and ground up glass to clay-rich bodies eventually led to the development of true stonepaste bodies.
The term faience is sometimes mistakenly used to describe Iznik stonepaste wares. The production of true faience goes back to 4000 BC in the Near East and Egypt, and several different techniques of faience production were used to make beads and vessels in these areas and elsewhere (see Section 3.9.2; Tite and Bimson 1986; Kingery and Vandiver 1986). Italian maiolica is also sometimes described as ‘Faenza’, the latter word having a French derivation which probably comes from the popularity in sixteenth-century France of wares made at Faenza, Italy. Maiolica was made by coating a calcareous earthenware pot with a white tin-opacified glaze, a technique now thought to have its origins in eighth-century Basra, Iraq (Mason and Tite 1997). However, one of the compositional differences between the glazes used in Islamic tin-glazed wares and of maiolica was caused by the probable use of wine lees as a source of the alkali in Faenza, introducing potassium rather than sodium (Tite 1991); Kingery and Smith (1985) refer to European (faience) products as ‘soft porcelains’. Medici porcelain is also quite different from Iznik pottery (Kingery 1986). Maiolica was produced in Spain and later in other Mediterranean and northern European countries, and as far afield as Mexico and South America. Maggetti et al. (1982) found that by combining an (semi-quantitative) X-Ray diffraction analysis with petrological investigation of the temper used they were able to distinguish clearly between European, Mexican and other products.
Compositional investigations, using neutron activation analysis, of maiolica bodies produced in the early sixteenth century in Castel Durante, Deruta, Faenza, Gubbio, Venice and Urbino in Italy shows a high degree of compositional similarity in the products (Myers 1992: 149–54). There is, however, a ‘tendency for objects painted in the same workshops to be compositionally similar to one another rather than to other objects in the group’ (ibid. 149). Given this intriguing tendency, a compositional investigation of the brilliant glazes used for decorating the wares from these same workshops in order to establish whether they, too, reflect the use of slightly different raw materials would be very interesting. Wilson (1987) has pointed out that those who signed, inscribed and dated their work regarded themselves not as artisans, but as artists. Some of the finest maiolica products acted as a means of marking the reconciliation between two elite families (Watson 1986: 56). It is clear from the highly fortified landscape of walled towns and cities in some of the areas of Italy in which maiolica was made and used, that competition and even war was not unusual.
The development of maiolica glaze technology included the precise application of pigments and the development of pigment technology. As Kingery (1993) has pointed out, prior to the fifteenth century manganese purple and copper green colorants were dissolved in the glazes. The development in the use of the painted pigment technology particularly in fifteenth-century maiolica, but also in the context of Iznik glazes, especially in the sixteenth century, characterised the impressive achievements of elite maiolica used as tableware. Although many of the crystalline pigments that were used, such as lead antimonate, were not new in the context of glass and glaze technology (see glass colours and glaze colours in Sections 3.2.5.5 and 4.3.5.2), painted designs using a wide range of colours (and including new pigments) was (Thornton 1997: 17).
In contrast to the earthenware body of maiolica, the bodies of Iznik pottery and other Islamic stonepaste wares contain a much higher silica content and are much harder. Because of their high silica content these pottery bodies are characteristically an opaque white colour. The kind of silica chosen was often naturally-occurring quartz, especially if low in iron, resulting in the desired white colour. A small proportion of clay was also added, which provided plasticity. Although hard, the pottery can contain quite a number of pores (i.e. it is porous) which means that, unlike Chinese porcelain, it may be weak. Although, as mentioned above, tin was introduced into some other Islamic glazes and maiolica as an opacified layer which provided a white background, in Iznik pottery and tiles the tin oxide is usually completely dissolved in the glaze so that the glaze remains translucent (see Section 4.7.9). A white background for glaze decoration in Iznik pottery is provided instead by a clean white slip. It is therefore clear that the technology of Iznik pottery is very different from the much earlier material faience, and from maiolica (Faenza).
The manufacture of Iznik can be regarded as an attempt to manufacture a hard white body, perhaps in response to the demand for Chinese porcelain. However, even though the visual results were impressive, as will become clear, neither the hardness nor the translucency of true porcelain was achieved.
Iznik is a city in western Asia Minor with a Nicaea in the fourth century BC (see Figure 4.39 for its location). It subsequently became a Roman and then a Byzantine city before coming under Ottoman rule in 1331, at which point it became known as Iznik. Iznik was the first major Ottoman capital to be relegated to second capital when the Ottomans conquered Constantinople. Documented estimates of the number of kilns in Iznik vary between an unbelievable 300 kilns during the reign of Sultan Ahmed (1607–17) to 9 kilns by the mid-seventeenth century when the industry had certainly declined. The highly decorated glazed products made in the distinctive Iznik style (which could also have been made at Kütahya) are likely to have been manufactured for relatively high status consumption, against a background of rusticated wares.
Figure 4.39 Location map of Iznik and other sites in Ottoman Turkey and beyond.
As mentioned above the term fritware is sometimes used to describe Iznik (and other Islamic pottery). It is worth considering whether the term is appropriate in rather more detail. Frit refers to a semi-fused mass of primary raw materials which are brought together in an initial stage of the manufacture of glass (see Section 3.3). Frit is formed from silica (either sand or quartz), an alkali (either mineral or plant ash) and often calcium oxide, aluminium oxide and sometimes lead oxide. In the case of Iznik ceramics, the addition of frit or of glass to the pottery raw materials leads to the formation of a glassy network once the material is fully melted into the body of the pottery (see Section 4.7.2 above).
A number of connected questions about the technology of Iznik form a focus for a broad investigation as to why Iznik appeared when it did, and under what conditions. Starting with the slim evidence of production, including kiln sites, historical references to Iznik production will be briefly reviewed in order to shed light on the context in which the pottery was made. The scientific examination of Iznik wares will then be linked to the archaeological and historical sources. Clearly, however, in adopting this methodology, it is necessary to have a series of specific research questions to focus on.
One question which relates to the development of the technology is to establish how the range of colours used in the superbly decorated range of Iznik wares was achieved and how these pigments developed over time, from the initial blue-and-white pottery, through to the exotic polychrome pots incorporating the striking bole red and finally ending in the seventeenth-century decline of the industry, producing second-rate products. Another aspect of the study is to examine the pot bodies in order to try and establish the raw materials used. The use of body and glaze raw materials can reflect different aspects of the same industrial organisation. The sources of exotic colorants used in the glazes may have changed over time, being sensitive to changing political allegiances or the exhaustion of colorant mineral deposit. The principal substances used for making the ceramic bodies on the other hand are likely to have been easier to obtain and to have involved contacts which were more localised than those involved in obtaining colorant minerals. The processes involved in the manufacture of glazes and ceramic bodies can therefore be the end result of a complex network of contacts between the person mining the colorant-rich minerals, the middlemen who supplied them to potential tradesmen who may then have sold them to, or exchanged them with, the potters. Scientific analysis can help to contribute in the investigation of these questions, provided that well-dated artefacts and those representative of the range of decorative styles are examined.
Another important source of information comes from the historical evidence. If texts are available, it may be possible to augment the scientific findings. As in all of the case studies reported in this book, one of the aims is to define the niche, or role, that the industry and its products played in society; the social and economic systems of Anglo-Saxon and early medieval Europe were worlds apart from those of Ottoman Turkey, so there would have been both similarities but also significant differences in the ways in which the organisation and function of the industries articulated with society.
Given the sudden appearance of high quality Iznik products, it is appropriate to examine a variety of possible contributory reasons, not just historical/socio-economic but also the origins of the industry from a technological viewpoint. This last involves a consideration of pottery and tiles that were used in Turkey before 1480, and a comparison of their technologies with the products of Iznik from its inception c. 1480, until its decline in c. 1650. The wares to be compared include, first, Chinese porcelain, second, rusticated ‘Miletus’ ware, a glazed earthenware, and third, the products of a group of potters known as the ‘Masters of Tabriz’. There is an obvious stylistic connection between the blue-and-white Chinese porcelain products and the early (and later) Iznik blue-and-white products, but the technology behind these different products needs to be compared. Little work has been carried out on the local ‘Miletus’ earthenware, so it is worthwhile investigating the technology involved in order to examine any possible influence on the origin of Iznik.
With respect to this third possible influence, there is historical evidence that a group of potters from Iran called the ‘Masters of Tabriz’ were invited by the Ottomans to oversee the massive production of tiles to decorate mosques and minarets prior to the appearance of Iznik, so in these investigations it was hoped to identify any technological characteristics which they may have introduced. They were involved in a highly ambitious project, the production of glazed tiles for the mosque complex of Sultan Mehmed I in Bursa, one of the first capitals of the Ottoman state, built between 1419 and 1424, which showed clear Iranian aesthetic (Atasoy and Raby 1989: 83). After this, in 1425, they focused their attention on the tile-work for the mosque of Murad II also in Bursa. Subsequently they had commissions to tile the mosques in Edirne, also an early capital of the Ottoman state: they tiled the Şah Malek Paşa Camii completed in 1429, the mosque of Murad II near Edirne completed in 1436 and Murad II’s mosque, Uç Şerefeli datable to between 1437–8 and 1447–8. Their last work was the so-called tomb of Cem Sultan in Bursa which was originally built in 1479. A completely different group of tilers were responsible for producing tiles for the famous ‘Tiled Pavilion’, the Çinili Köşkü, in Istanbul, dated 1473 (Atasoy and Raby 1989: 89).
Finally, a non-technological reason needs to be offered as to why it was that Iznik pottery appeared when it did. What was it that brought about its introduction?
Excavations of kilns at Iznik have revealed two kinds of structures. The first was the lower parts of what were probably two-chambered circular kilns (see Figure 4.40): the firing chambers (Aslanapa 1969: 146, Figure 5). The second kind was described as rectangular measuring 1.5 × 1.8 m in plan, surviving to a height of 2.5 m and described as ‘small’. Recesses were visible inside this second kiln type which, it is claimed, were for shelves; one illustration shows that this kind of kiln had a rounded end (Aslanapa 1969: Figure 3). It is suggested that this rectangular kiln type had ‘transverse arches’ and is reminiscent of such kilns found in other Islamic contexts, such as Merv, Turkmenistan (Dr St J. Simpson, personal communication) and eighth–ninth–century Islamic contexts in al-Raqqa, Syria (Henderson et al. forthcoming). It is notable however that no Iznik wasters were found in these excavations at Iznik, only those of Miletus ware (Aslanapa 1969: 142) together with many Iznik sherds. However, although the Iznik kilns are primary evidence for pottery production, there is no direct evidence that these kilns were used for the manufacture of stonepaste wares and it is likely, though not proven, that they would have been used for the manufacture of earthenware. Although a higher temperature would have been necessary for the production of Iznik stonepaste wares, the question of what precise structural differences there may have been in the kilns used to fire fritware rather than earthenware (if any) must remain speculative until a kiln for firing stonepaste wares is excavated.
Figure 4.40 Plan of the kilns found at Iznik
(after Aslanapa 1969).
Abū’l Qāsim’s treatise, consisting of two manuscripts dated 1301 and 1583 respectively, describes Iranian fritware technology (Allan 1973) which would probably have been that used for the production of Iznik ware. The treatise includes reference to both kiln bars and saggers (ibid.: 114): the complete pots each inside its own lidded sagger would have been placed on a kiln bar which would have been inserted into the kiln wall. The saggers would have protected the pots from variations in kiln atmosphere, from vitreous fuel-ash and from the dripping glaze derived from other pots. The kilns were fired for twelve hours using wood such as hyssop, walnut and willow. The willow was stripped of its bark so that it did not smoke – had it been allowed to it could have created a more reducing atmosphere and may have reduced the lead oxide found in (Iznik) glazes to lead metal and in so-doing blacken the pots. The pots were allowed to cool down for a week.
No evidence for the use of these techniques has so far been found at Iznik, though fritware pots definitely made at Iznik (according to their dated inscriptions) do not bear the telltale cockspur marks that would have been left as a result of using tripods for separating and stacking the pots, so saggers are very likely to have been used. Whitehouse mentions the use of kiln bars at Siraf (Whitehouse, 1971: 15) and saggers were used at Takht-i Sulimān. Recent excavations of a pottery dump from an eleventh-century workshop at al-Raqqa, Syria, has provided more evidence for the use of kiln bars and saggers in an Islamic context (Tonghini and Henderson 1998). Abū’l Qāsim’s treatise describes the procedure for making the ‘frit’ component of the pottery (the partially fused primary raw materials of glass which is mixed with ground up silica), as opposed to fritware pottery, in a kiln called a biraz. The process takes eight hours during which the mixture is well mixed. The structures described and illustrated by Whitehouse (1971: 15, Plate VIa), which he excavated at Siraf, were quite possibly fritting kilns: ‘Each comprised a fire box and a chamber containing an oval earthenware tray.’ He suggests that they would have been used for making glaze, but the discovery of earthenware trays suggests that there may be an alternative explanation: that they were used for fritting. Normally the mixture to be fritted would be raked from time to time in such trays (see Section 3.3). Glazes/glasses are normally melted in crucibles or in tanks (see Section 3.4). Abū’1 Qāsim mentions the mixing of the frit with the clay (Allan 1973: 114).
With one exception, all the kiln debris and wasters from Iznik so far published derive from the manufacture of Miletus earthenware: the exception is the discovery of small ceramic fragments which had been used as testers, including for the testing of distinctive bole red glaze. These fragments have holes drilled through them and it is thought that the potters were able to hook them out of the kiln without disturbing the rest of the pots (Atasoy and Raby 1989: Figure 44). At Kütahya, another probable production centre for Iznik fritware, Şahin (1981) has published excavations of (earthenware) painted pottery and tile kilns where the minimum internal diameter is 1.2 m, but again no kilns unquestionably associated with fritware production have been found.
It is clear from the registers relating to the Topkapi Palace treasury and kitchens in Istanbul that Iznik pottery was regarded as a prestigious ware. A reference is made to the purchase of 541 Iznik plates, dishes and bowls from the bazaar in Istanbul in 1582 for the sumptuous banquets which were held to celebrate the circumcision of Prince Mehmed, the son of Sultan Murad III, which lasted 52 days and nights (Atasoy and Raby 1989: 14). Although regarded as prestigious, Iznik was never regarded by the Sultan as being in the same class as Chinese porcelains: 10,600 pieces of porcelain are held in the Topkapi Palace today. The historical research into Iznik pottery by Nurhan Atasoy was largely based on three types of documents: schedules of fixed prices, inventories of the effects of deceased persons and palace registers. The last category includes records of gifts presented to the sultan, items deposited and issued by the palace treasury and the payrolls of craftsmen employed by the palace. Specific wares are referred to as ‘porcelain’, ‘celadons’ and ‘pottery’ and whether they are Ottoman products. For some of the later Iznik wares, the production centre is recorded. Apart from Istanbul and Kütahya, Iznik is mentioned exclusively in documents dating to between the end of the fifteenth century and the early eighteenth century. In 1570 four master potters were even brought from Iznik to Istanbul, along with the tools of their trade (Atasoy and Raby 1989: 23). However, the position of Kütahya as a production centre in relation to Iznik and to Istanbul still needs to be examined scientifically, and if possible archaeologically, in detail; given that the ‘Iznik’ wares made at Kütahya are indistinguishable technologically from those made at Iznik itself, it must have formed a significant part of the production and distribution network.
By the mid-seventeenth century the quality of Iznik ware had declined, and it is only from about this time that in the schedules of fixed prices Iznik is referred to explicitly as the place of origin (Atasoy and Raby 1989: 25). An explanation for this is that Iznik would have been competing with other centres of provincial production, such as Kütahya. Among the probate inventories studied, one in which Iznik wares are mentioned specifically is worth describing in detail in order to provide a flavour of its status and relative ‘social’ and economic value. A probate inventory dated 1548 for Hâce İshak bin Abdürrezzak, a draper and clothier who had stocks in the Cloth Merchants’ Hall in Edirne and the Caravanserai of Halil Paşa, and who owned houses in Edirne and farms in the country, mentions Iznik pottery. He can certainly be regarded as rich and owned eleven Iznik dishes and four pieces of Chinese porcelain (Atasoy and Raby 1989: 26). Among the other inventories are those for members of the military class, who also owned Iznik ware; members of this class could practise farming and stock-raising and often owned slaves.
The payrolls of craftsmen employed by the palace might be expected to provide some fascinating insights into the organisation of Iznik pottery and tile production. However, as Attasoy and Raby (1989: 32) note, although documents are available in which, for example, the name of the master tiler, the names of his apprentices, their daily wages, the name of the sultan who took them into the palace, and even their ethnic origin, is stated, information about whether they made the tiles themselves or whether they were only responsible for setting the tiles in places on walls is lacking. Nevertheless, such information is of great interest in that it provides a clear description of the hierarchy of the production organisation within the Palace.
As for documents relating to the technology of production of Islamic fritware, one of the most important is the treatise by Abū’l Qāsirn (Allan 1973) written in 1301 (mentioned above) which includes a section on pottery in the chapter on precious stones. The recipe for the production of fritware cited by him is ten parts of silica, one part of glass frit and one part of fine white clay; it is presumed that the ‘parts’ are by volume, rather than by weight. Abūl Qāsim’s recipe describes a special fritting furnace in which the primary raw materials of glass production were melted’ together. However as noted in Section 3.3 the intention when fritting is to arrest the fusion of raw materials before a glass is produced, though the treatise suggests that glass was produced:
This [shakhār from Baghdad or Tabriz] is cooked over a slow fire [for six hours], and is stirred from morning till night with an iron ladle made as large as the diameter of the kiln until it is well mixed [and becomes white] and it becomes one, like molten glaze, and this is the material for glass vessels. After eight hours they take out the brew by the ladleful. Below, in front of the oven, is a pit full of water, into which they put the glass frit. When water and fire meet there is a great noise and roaring like thunder, which for all the world could be real thunder and lightning [such that everyone who has not seen it and hears the noise falls on his knees shuddering and trembling]. The craftsmen call this mixture jawhar and store it, until the time comes to compound it, in a broken up, powdered and sifted form.
(Allan 1973: 113)
It is apparent that once the raw materials were fully fused they were thrown into a pit with water where it would have shattered (devitrified) into silicate crystals. The material produced (glass or silicate crystals) is therefore not the same thing as a true frit, which would be partially fused glass raw materials with a granular consistency. It is interesting though that during the fritting process the frit is also thrown into cold water, several times. In this case it only occurs once – presumably the shattered glass produced is easier to store and to mix with the other ingredients in the manufacture of Iznik. Finished Iznik pots contain a network of glass which could either have derived from the addition of (re-) melted silicate crystals or frit which would have melted fully into glass during the firing process. If the material described above was used then clearly real frit was not used. Although this procedure would probably have been followed in principle by Iznik potters, another stage would have been the addition of lead (and tin) at some point in the production process: this is also described by Abū’l Qāsirn (Allan 1973: 113).
Fuel consumption for firing the Iznik kilns is discussed by Anhegger (1941: 176–77). He refers to a document dated 1719 which describes the demand for fuel for the kilns. Demand for pine wood was such that the naib (judge) of Iznik and the governor of the province of Kocaeli were asked to provide 50,000 kilos for the kilns at Tekfur Sarayi. It was clear that only a certain quality of wood would be accepted because of its combustion characteristics: without resin or knots. The presence of knots would tend to cause the wood to burn at differential rates causing hot spots in the kiln and potentially resulting in some failed pots. The amount of smoke produced would have a direct effect on the atmosphere of the kiln and therefore the resulting colour of the pottery and its glazes; in Abū’l Qāsim’s recipe it is noted that bark can sometimes cause too much smoke (Allan 1973: 114).
Iznik pottery follows a relatively well-dated developmental sequence of glaze decoration. The date ranges applied to this development are based on the building dates of Ottoman mosques decorated with tiles which display the same designs (see Table 4.2). Because the dates are relatively secure, it is possible to trace the ‘emergence’, development and decline of Iznik pottery. From c. 1480 to 1520 a tight introverted form of (mainly) spiral blue-and-white decoration is used, known as early blue-and-white which, like all the other Iznik types of decoration, has a colourless overglaze. From c. 1520 to 1540 an extra colour – turquoise blue – was added and this decoration in a more open form is known as the two blues. An example of this ware dating to c. 1530 is shown in Figure 4.41, a typical example of potters’ style ware. The third variety of glaze decoration in the sequence is known as Damascus ware. This type of decoration which was used during the 1550s involves the use of a much wider range of colours among which are an aubergine purple, deep cobalt blue and a sage green (see Figure 4.42). The fourth kind, slip-painted ware, as the name suggests, incorporates a second colour of slip as well as blue, ‘black’ and other colours of glaze. Rhodian glaze decoration used between 1570 and 1580 incorporates the widest range of decorative colours and includes a colour which is applied in relief and can vary between a tomato-coloured red and a yellow orange colour; this is known as bole red. The next decorative variety, late blue-and-white, consists of a far more open and exuberant pattern than used in early blue-and-white. It was in use between c. 1580 and c. 1600. Iznik pottery was still being produced in the seventeenth century, but by 1650 the products weres second-rate with the glaze no longer adhering to the pot properly and the slip no longer having the brilliant white colour of sixteenth-century Iznik (see below).
Table 4.2 List of Ottoman pottery samples taken for microprobe and SEM analyses
| Date | Description |
| 1430 | ‘Masters of Tabriz’ blue-and-white |
| c. 1460 | Miletus ware blue-and-green |
| 1480 | Blue-and-white from Iznik |
| 1510 | Blue-and-white from Iznik |
| 1520 | Blue-and-white from Iznik |
| 1530 | Tugrakes spiral blue-and-white from Iznik |
| 1540 | Potters’ style Grape dish fragment blue-and-white with turquoise from Iznik |
| 1550s | Damascus ware dark, blue, olive green, turquoise, ‘black’ outlines from Iznik |
| 1560–70 | Slip-painted. Red slip, blue-and-white from Iznik |
| 1580 | Rhodian ware. Bole red, blue and emerald green from Iznik |
| 1580 | Rhodian ware. Bole red, blue, turquoise, emerald green and ‘black’ from Iznik. |
| 1580 | Late blue-and-white from Iznik. |
| c.1650 | Emerald green, blue, ‘black’ and red. |
Figure 4.41 Typical example of potters’ style ware
(after Atasoy and Raby 1989).
Figure 4.42 Typical example of ‘Damascus’ ware
(after Atasoy and Raby 1989).
It was with these archaeological and historical considerations in mind that small samples of the tiles and pottery were mounted in epoxy resin discs so that that could be examined analytically using an electron microprobe and visually under magnification using a scanning electron microscope (SEM). Using the SEM individual inclusions could be photographed and analysed in ceramic bodies, slips and glazes. As well as this, by using an SEM, variations in the chemical composition of the glazes, such as the presence of a cobalt-rich painted design (as reflected in the grey level/average atomic number – see Section 2.3) could be photographed. A glaze rich in a heavy compound, like lead oxide, will appear a paler grey colour than a lighter compound, like silica. High quality quantitative analyses could be obtained for the glazes using an electron microprobe.
First, the technological characteristics of Iznik products from 1480 to 1650 will be described. The possible technological influences of Chinese blue-and-white, ‘Miletus’ earthenware and the ‘Masters of Tabriz’ products will then each be considered in turn.
In the scientific analysis of Iznik ceramics thirteen pottery samples were examined, all of which derived from Iznik, or were derived from dated Turkish monuments. They ranged in date from 1430 to 1650 and included examples which represent the full stylistic range of Iznik pottery. In addition to the pottery, a series of fifteenth- and sixteenth-century Turkish tiles were examined for comparison and in order to investigate links between pottery and tile technologies (Henderson and Raby 1989). The samples examined are listed in Table 4.2 with their likely production dates.
From an analytical point of view it was seen to be important to determine how the pottery body was made, how the white background to the glaze was achieved and what was used for colouring the glazes. A discussion of the colorants will follow a consideration of the major compositional characteristics of the bodies.
Figure 4.43 is a photomicrograph of a thick section through a typical Iznik pot, revealing a (lower) zone of pale body, a clearly delineated thinner slip layer lying on top of this and, virtually invisible under the conditions of illumination, a thin translucent glaze layer. If a specimen of Iznik pottery is examined under a scanning electron microscope using a back-scattered detector to display contrasts in average atomic number (i.e. chemical composition; see Section 2.3) its different structural characteristics come into sharp focus (see Figure 4.44).
1 the lowest layer shown (above the micron scale bar) is the silica-rich body, with a network of lead-rich glassy ‘frit’ showing as a pale grey colour (see Figure 4.45). Within the body fabric are larger dark areas which are voids in the fabric;
2 above the body layer is a generally darker grey silica-rich layer – the slip. It contains noticeably smaller silica crystals than the body and a smaller proportion of lead-rich frit;
3 above the slip layer is the interface (or interaction) layer showing as silica crystals bathed in a white lead-rich glaze;
4 the surface layer showing as white is a high lead translucent glaze.
Figure 4.43 A photomicrograph of a mounted section of typical Iznik pottery body and glaze. The distinction between the white slip layer (which incorporates a large black void) and the body can be seen clearly.
Figure 4.44 A back-scattered scanning electron micrograph of a typical Iznik body showing the surface (‘white’) glaze, the interaction layer containing (‘black’) silica crystals, the slip layer with fine silica crystals and the body containing larger silica crystals, voids and a higher proportion of ‘white’ glassy phase than in the slip.
Figure 4.45 A back-scattered scanning electron micrograph of the glassy (‘white’) phase that has developed between silica crystals in an Iznik body.
The first two and the fourth of these structural characteristics are detectable in all Iznik pottery types. The depth of the interaction zone can vary (Henderson 1989b; Tite 1989).
Analysis of the body of Iznik blue-and-white pot sherds dating to c. 1520–40 showed that in addition to the high proportion of silica (ground quartz or sand) and the frit, there was also a small proportion of clay which when combined with the frit produced variations in composition (depending on the type and composition of the clay used). The occurrence of magnesia, aluminium and calcium in the body frits can be attributed to the use of the clay component. This feature was also found in other Iznik pottery bodies. Occasionally tin was detected in the body of Iznik ceramics, specifically in the glassy ‘frit’ phase of a blue-and-white pot tested. If one takes a closer look at the glassy frit phase in the ceramic body (Figure 4.45) it can be seen that the pale grey angular silica crystals are mainly surrounded by a white glassy layer and interspersed between (black) voids in the potsherd.
Close examination of the glaze showed that a few relict silica crystals were often suspended in the glaze and occasionally a few small (white) tin crystals. In fact it was found that normally between about 3% and 6% tin oxide was completely dissolved in Iznik glazes. In general the principal components of Iznik glazes are the oxides of sodium, silicon, lead and tin, with traces of magnesia and aluminium. Indeed this type of lead oxide-soda-silica plus tin glaze is typical of all the Iznik sixteenth-century glazes analysed and found in samples of all the stylistic variations analysed.
The second stylistic type of Iznik pottery considered was multicoloured Damascus ware (see Figure 4.42). Although the ‘style’ of glaze decoration is obviously quite different, not only is the technique of making the body the same as for blue-and-white, but so is the basic composition of the glaze.
The sample of slip-painted ware analysed has a complex series of layers. The ceramic consists of a central silica-rich body (a pale buff colour), with white slip layers on both inner and outer surfaces. On top of the white slip is a further (red) slip layer. Covering this is a glaze consisting of a bluish underglaze, the whole thing being sealed by a colourless glaze. The red slip decoration is only used on part of the pot surface, so the white slip is revealed in places. X-Ray fluorescence spectroscopy has revealed that all the layers are rich in lead, including the glaze, both slip layers and the frit in the body; a lead map showed the highest ‘relative’ lead level in the glaze, slightly less in the interaction layer, a variable and lower level in the slip layers, with slightly more in the outer red slip layer than in the inner white slip layer and apparently least of all in the silica-rich body. In general, most Iznik pottery analysed contained a higher proportion of lead frit in the body than in the slip layer. There can be no question that the presence of lead in all components of Iznik ware helps the fit of the glaze. This slip-painted ceramic presents a challenge to the potter because of the complex structural considerations associated with two slip layers which could potentially reduce the possibility of achieving the appropriate relative contraction of each component as it cooled – a proper glaze fit.
Rhodian samples incorporate the use of bole red used in relief, and display a wide range of glaze colours. The bole red is evidently produced as an application of a kind of red iron-rich slip, probably modified by the development of a translucent reddish glass. Variation in the colour of ‘bole red’ and the orangey reds found in other Iznik pottery (described as ‘bole’) are probably attributed to the different firing characteristics of the colorants (particularly copper) in the red glassy phase. Further research is needed in order to sort this problem out properly. Chemical analysis using proton-induced X-Ray emission shows a high iron content and some copper associated with the slip. Examination of the bole red layer using a scanning electron microscope (see Figure 4.46) shows that it consists of silica and iron-rich crystals bathed in a lead glaze, with a higher proportion of larger silica crystals (appearing grey) lying at a lower level in the glaze, as would be expected. An interesting feature of bole in Figure 4.46 (an interpretative illustration is provided in Figure 4.47) is the basal layer of minute spinel crystals, which would have formed a dark paint applied to the surface of the white slip and used to mark out the area within which the bole was to be applied. The spinel crystals appear in the electron micrograph as a layer of small white crystals lying on and partly in the underlying silica slip layer in Figures 4.46 and 4.47. The white layer lying over the bole is the base of a lead-rich glaze. Without mounting a section of this kind, and examining it under the SEM, it would not have been possible to identify dark paint used for laying out the decoration, since it was completely covered by the bole red decoration.
Figure 4.46 A back-scattered scanning electron micrograph of a section through bole red pigment decorating the surface of an Iznik pot.
Figure 4.47 An explanatory diagram of Figure 4.46.
The sample of late blue-and-white Iznik pottery analysed which dates to about 1580 and an Iznik tile dating to around 1600 both have the familiar three-component structure: a lead-frit body, lead-rich slip and lead oxide-soda-silica glaze. The latest pot examined from Iznik dates to c. 1650. In spite of some similarities in the attempted decoration from that achieved in preceding Iznik pottery styles, by this time it is evident that the technology of ceramic production was in decline. In the production of this mid-seventeenth-century pot the silica used was coarser, with maximum crystal size increasing to c. 400 microns, compared to c. 100 microns in mid- sixteenth-century Iznik ceramics. Another technological feature which distinguishes this pottery from the finer earlier material is the occurrence of bone ash in the body, where the calcium in the bone ash probably acted as a flux, and the phosphorus possibly as a glass-former, producing a random distribution of glassy areas. This is an early example of its use in a European context. Although lead- and tin-rich glassy inclusions are present in the seventeenth-century sample, they do not form part of the full interconnected glassy network seen in the earlier Iznik pottery, as if the knowledge of production techniques had only been partly remembered. A poorly formed glaze, which ‘rolls’ off the surface of the pot is a further technical characteristic which illustrates the decline of this ceramic technology. This pottery clearly marks the decline in quality of Iznik production.
Various features of ceramic technology are important in the effective development of glazes and glaze colours. Although discussed in Section 4.3.5, some of these bear repeating in the context of Iznik glaze technology. The gross composition of the glaze will directly affect the colour which is achieved in the glaze; for example when copper is used as a colorant, the colour will vary between turquoise in lead oxide-soda-silica glazes (as in Iznik glaze), green in lead-silica glaze and blue-green in alkali-silica glazes. The depth of the observed colour will also be affected by the average atomic number of the major constituents; a high proportion of lead oxide will lead to a greater absorption of light wavelengths so that the colour will appear to be of a darker hue. Apart from the gross composition of the glaze, the maximum temperature reached by the kiln, the oxidising-reducing conditions, and the cooling cycle will all affect the successful adherence of the glaze to the ceramic body (its fit). The chemical composition of the body of the pot, and by inference, the crystalline composition and water content of the original clay used, will all affect the fit of the glaze, as will the fineness of the slip, if used. In the case of Iznik pottery the presence of lead in the body, slip and glaze allows the glaze to fit efficiently by reducing the potential differences of contraction on cooling and minimising random cracking or shivering of the glaze. The presence of lead in Iznik glaze provides elasticity which helps the glaze fit. The fit may also be improved by the presence of dissolved tin.
In spite of the wide range of decorative styles employed by Iznik potters the composition of the glazes employed varied little until the decline occurred in the seventeenth century. The glaze composition used in all cases was found to be a lead oxide-soda-silica type (Henderson 1989b: Table 2). Another feature which is characteristic to Iznik is that tin oxide is dissolved in the glaze at a level of c. 5% Henderson 1989b; Tite 1989). The lead oxide dissolved in Iznik glazes imparts a brilliant translucence which shows off the decoration, mainly underglaze, to its best advantage.
Electron microprobe analysis can determine what colorant-rich minerals have been used in order to develop coloured underglazes. As we have seen, the Iznik potters used a white slip as background with cobalt blue or pale green underglaze, which often also coated the internal face of the pot. They used a whole range of glaze colours: turquoise, sage green, emerald green, bole red and purple (apparently black), which produced some intricate and beautiful results. Cobalt blue is a colour that was used throughout the Iznik tradition. Cobalt occurs in nature as a cobalt-rich mineral (i.e. cobalt when used as a colorant has a suite of chemical impurities associated with it: see Section 3.2.5.1 ). The levels of these impurities changed over time in Iznik ceramics and since they can sometimes be related to mineralogical deposits exploited we can infer that the source for the cobalt mineral used also changed. In the late fifteenth and early sixteenth centuries the impurities detected with the cobalt were iron, nickel and copper. This suggests that a manganiferous cobalt source was used. From c. 1530–60 an arsenic-rich cobalt source was apparently used in Iznik blue glazes. The blue-black pigment used for the linear decoration of a mid-sixteenth-century tile contained cobalt, manganese and arsenic which infers that arsenical cobalt was used, and that the manganese may have been introduced as an additional impurity from an alternative source. One arsenic-rich source for cobalt is the Black Forest in Germany, and there are others in Europe, associated with ancient Massifs; cobalt is also found in Persia and this source was probably used for decorating Kashan wares. Manganiferous sources are found in China but without more analyses, we cannot at this stage establish with confidence which precise sources were used in Iznik blues.
Manganese by itself was found to be the cause of the colour of the translucent purple Iznik glazes. Green colours were produced by iron oxide combined with copper oxide, with occasional detection of chromium; the emerald green glazes were found to contain more iron oxide and less copper oxide. The dark, apparently black, outlines used from about the mid-sixteenth century are due to a high density of pigment particles: the dark green outline in Rhodian pots was found to be coloured by iron and copper, and have been identified by Professor Michael Tite as chromite particles (Tite 1989). Chromite particles were also found to have been used as an applied pigment which was used for defining areas of decoration, as in the case of the application of bole red, described above.
In order to examine how other ceramic technologies may have influenced the emergence of an apparently fully-fledged Iznik pottery technology in 1480, the technology of other locally produced ‘rusticated’ wares or ‘peasant wares’ (Carswell, in Petsoploulos 1982) needs to be examined. Examples of this are the so-called Abraham of Kütahya wares (Carswell and Dowsett 1972) and Miletus earthenware (Figure 4.48). In addition, other possible influences on the emergence of Iznik pottery need to be examined, especially Chinese porcelain and the bodies of ‘Masters of Tabriz’ tiles and pottery.
Figure 4.48 Typical example of Miletus ware
(after Atasoy and Raby 1989).
Figure 4.49 shows a back-scattered electron micrograph of a fragment of Miletus earthenware dating to about 1460. If this micrograph is compared with Figure 4.44, a section of Iznik, several differences can be seen. In the Miletus pottery there is no frit component at all, and a series of cracks through the body shows the presence of structural weakness not generally found in Iznik pottery. We can therefore say with confidence that the origins of the bodies of Iznik pottery are unrelated to that of Miletus ware, even if some similar colorant minerals were used.
Figure 4.49 A back-scattered electron micrograph of a section through Miletus ware.
In view of the use of blue-and-white glaze decoration from the earliest phase of Iznik production, one might suspect that Chinese porcelain technology contributed to the development of Iznik. However, as can be seen in Figure 4.50 the microstructure of high aluminia Chinese porcelain is also entirely different from Iznik pottery with a lack of slip layer and more finely ground silica crystals. Perhaps a more likely source of technological influence might be that attributed to the ‘Masters of Tabriz’. Some of the ‘Masters of Tabriz’ tile glazes analysed were all found to be of a lead oxide-soda-silica composition. Like Iznik glazes the ‘Masters of Tabriz’ glazes contained tin, but it was not only generally found at slightly higher levels, but mostly present as crystals in suspension (Figure 4.51). Since tin-opacified glazes were introduced much earlier in the Islamic world (Mason and Tite 1997) these glazes are therefore to be regarded as forming a continuation of an earlier tradition. Iznik potters used a far wider range of glaze colours than the ‘Masters of Tabriz’ who used only monochrome dark blue, turquoise and blue-and-white for tile decoration. While the mineral colorants used were basically the same as used by Iznik potters to make these colours (cobalt, copper and tin oxide respectively), the use of the colorants is often excessive, for example by using excessive cobalt to produce an apparently ‘black’ glaze instead of cobalt blue. It is also clear that the firing conditions sometimes went wrong. An example of this is where metallic lead was found to be in a suspension of a pale blue glaze decorating a tile from Mahmud Pasa Turbesi dated 1474 (see Figure 4.51). This indicates that the glaze was fired under reducing conditions changing the lead oxide (in a translucent glaze) to droplets of lead metal producing a partially opaque glaze. Although there are similarities in the glaze technologies of Iznik and ‘Masters of Tabriz’ tiles there are clearly also significant differences.
Figure 4.50 A back-scattered electron micrograph of a section through Chinese porcelain.
Figure 4.51 A back-scattered electron micrograph of masses of tin oxide and lead oxide crystals which appear white. The glaze is pale blue in colour and is from Istanbul, Mahmud Pasa Turbesi dated to 1474. The fact that the lead has crystallised out of solution indicates that the glaze is ‘unsuccessful’ because the firing conditions have been too reducing.
The results for the analyses of a series of fifteenth-century Turkish tile bodies dating to between 1426 (the mosque of Murad II in Bursa) and 1474 (the so-called tomb of Cem Sultan in Bursa) are published elsewhere (Henderson and Raby 1989), so a summary will be given here. Figure 4.52 shows a polished section of a tile from the Muradiye in Edirne dated to 1436, a typical example of’Masters of Tabriz’ work. A very limited development of an alkali-lime frit is visible (appearing white) covering some of the (grey) silica crystals. The development of this glassy phase is very limited when compared to its full development in Iznik pottery. The randomly distributed bright (higher atomic number) inclusions have lead oxide, tin oxide, lead oxide-silica-calcium oxide and lead oxide-silica-tin oxide compositions. The microstructure and composition of this tile body attributed to the ‘Masters of Tabriz’ is therefore quite different from that of the ‘Iznik’ potters (compare with the body of Figure 4.43). From the series of tile analyses carried out, the technology used for making the body of cuerda-seca tiles and underglaze blue-and-white tiles in the Muradiye mosque in Edirne was the same, differing little from the technique used for making tiles in the so-called Cem Sultan Tomb in Bursa – these last tiles are attributable to the tradition of the ‘Masters of Tabriz’ and so they might be expected to be closest in technology to Iznik products.
Figure 4.52 A back-scattered electron micrograph of the body of a ‘Masters of Tabriz’ tile showing the high proportion of large silica crystals and a very limited development of a glassy phase.
It could be argued that the occurrence of a random distribution of lead-rich glassy ‘frit’ of similar composition to the lead oxide-soda-silica glazes found in some of the tiles tested (but not all) suggests that the technology was undergoing an experimental or transitional phase. The evidence for this is very weak, especially since most ‘frit’ that occurs in the tile bodies is of the alkali-silica composition and is not lead-rich as found in Iznik. The alkali-silica frit is more likely to represent a form of continuity from an existing Islamic ceramic tradition. Some tiles examined contained no detectable frit at all, so it is not possible to detect a clear developmental phase in tile body technology through the period up to c. 1480.
The analysis of a single sherd of blue-and-white pottery dating to c. 1430, which can be attributed to one of the painters who decorated the blue-and-white tiles in the Muradiye Mosque in Edirne, shows that in the occasional production of such pottery by the ‘Masters of Tabriz’ the same alkali-silica frit with a smaller number of randomly distributed lead-rich glassy areas was used as can be found in their tile-work.
When compared to Iznik compositions the ‘Masters of Tabriz’ glazes are mainly similar in being a lead oxide-soda-silica (+ tin oxide) type, but in addition there is some marked variation in the composition of the glazes found in the tiles used for decorating Mahmud Pasa Turbesi, Istanbul, dated to 1474 where lead oxide-potassium oxide-silica (+ tin) and a lead oxide-silica (+ tin) were found. In the glaze of the pottery fragment attributed to the ‘Masters of Tabriz’, the major components were lead oxide, soda and silica, but the lead oxide was present at a significantly lower level, at 4%, than found in Iznik glazes (at 20–30%).
So we can suggest with some confidence that the locally-produced Miletus ware and the ‘Masters of Tabriz’ tile and pottery technology did not lead directly to the development of Iznik pottery, and also that Chinese blue-and-white porcelain technology is entirely different. Around 1480–90, we might expect the earliest Abraham of Kütahya ware to provide a clue. A blue-and-white potsherd of this type from Iznik was found to be made with a fully developed lead-rich frit. However, the frit was found to contain a lower lead content and can be regarded as transitional in technological terms from the fully-developed Iznik frit technology, which appears around 1510. The body of a tile from Bursa dating from 1512–13 shows characteristics of a non-standardised technology, or possibly one in transition, with multiple layers of ceramic raw materials, including a layer of ‘slip-like’ material sealed beneath a layer containing larger crystals (see Henderson and Raby 1989 for further discussion). So although pottery technology was standardised by c. 1510, tile technology was perhaps still in a state of flux at this time. It is however worth considering the possibility that there was not the same need to produce a perfect tile body with the right weight and thickness as in the manufacture of Iznik pottery; it was, after all, only the glazed tile surfaces which were seen – and some at a distance.
Thus here we have apparent evidence for the origins of the manufacture of Iznik pottery; though it clearly resulted from a very complex situation in which location and chronology should be seen as two very important parameters. The technological development appears to have resulted from new local, rather than external, factors. Court patronage would certainly present the most likely motivation for new developments and near perfection in Iznik technology.
Although the technology of Iznik, and of some of the wares which preceded it and were contemporary with it, are relatively well known the evidence for production sites and a discussion of its internal dynamics are relatively thin on the ground. In the absence of the discovery of kilns that were definitely used for firing Iznik, other sources of evidence must be considered. For this period one important source of evidence is historical.
Atasoy and Raby (1989: 74) note that Iznik was certainly not the only pottery production centre in the sixteenth century. Diyarbakir in eastern Turkey produced provincial imitations of Iznik; in the early eighteenth century Iznik potters working at the Tekfur Sarayi kilns in Instanbul produced Iznik-style tiles; the potteries of the Golden Horn in Istanbul, at least in the seventeenth century, produced earthenware. John Carswell (Carswell and Dowsett 1972) has made the point that there is documentary evidence for Kütahya being an important production centre in the sixteenth and seventeenth centuries. Two vessels bear inscriptions in Armenian which date the vessels to 1510 and 1529 and both refer to Kütahya as the centre of production. The critical point to make here is that these pots might easily be classified as products of Iznik since the same technology is involved (Tite 1989). Given that only a small number of these products are inscribed with primary evidence of where they were manufactured, there is every reason for suspecting that a large number of other wares were made at Kütahya.
The Palace of Sultans at Topkapi in Istanbul was the centre of a vast well-administered Ottoman empire; thousands of people lived and worked in the palace. It was from the palace that the highly centralised government of the empire was run and one part of this organisation was the manufacture of Iznik, by dictat.
Designs for Iznik pottery and the patronage of the court in Istanbul are irrefutable facts. However, demand for Iznik was such that during some periods, such as in the late sixteenth century, the Sultan had to issue an imperial decree which reprimanded the potters of Iznik for delaying the delivery of tiles caused by the demands for Iznik ware used in domestic consumption and for export.
The structural and microstructure features of Iznik pottery bodies can now be defined as consisting of a high silica body (mistakenly referred to as ‘faience’) containing a lead frit and a small amount of clay, a white slip layer normally containing lower lead levels than the frit, and a lead oxide-soda-silica surface glaze in which tin was dissolved. This technology was used for the manufacture of the Abraham of Kütahya wares, Golden horn wares, Damascus wares, Slip-painted wares, Rhodian wares and Iznik tiles of the sixteenth century. The range of colorant raw materials increased over this period, with the fullest range being used in Rhodian wares which included bole red applied in relief. The origins and initial development of this technology lie somewhere in the late fifteenth century, and apparently locally; this is the time when the principal structural characteristics of Iznik ceramics were first developed, followed in the mid-sixteenth century by the full development of a very wide range of colorants in the glazes. Earlier technologies of the ‘Masters of Tabriz’ tile-work and the local Miletus pottery bear little relation to the technology of Iznik, even though some characteristics of the glaze technologies are common to both. Technologically there is little to relate Chinese blue-and-white porcelain to Iznik even though it is likely to have provided the stimulus for the production of Iznik blue-and-white. Court patronage is likely to be the explanation/motivation behind the new technological developments, and since these developments occurred over an apparently relatively short time, any possibility that the features associated with the ‘Masters of Tabriz’ technological tradition contributed to the emergence of Iznik technology is small. By the mid-seventeenth century the technology of Iznik pottery is clearly in decline; the quality of the glaze, its fit and the technology of the pottery body were in stark contrast to the near perfection and brilliance of Iznik at its peak.
Allan, J.W. (1973) ‘Abū’l Qāsim’s treatise on ceramics’, Iran 11: 111–120.
Allen, C.S.M. (1991) ‘Thin sections of Bronze Age pottery from the East Midlands of England’, in A. Middleton and I.C. Freestone (eds), Recent Developments in Ceramic Petrology, British Museum Occasional Paper 81, London: British Museum Publications, pp. 1–15.
Allen, C.S.M. (forthcoming) ‘Accessory cups of the Bronze Age in Lincolnshire’, submitted to Proceedings of the Prehistoric Society.
Allen, C.S.M., Knight, D. and Williams, D.F. (1999) ‘Vessel fabrics’, in L. Elliott and D. Knight (eds), ‘An early Mesolithic site and first-millennium BC settlement and pit alignments at Swarkestone Lowes, Derbyshire’, Derbyshire Archaeological Journal 119: 79–153.
Anderson, R.P. and Guo Yanyi (1995) ‘Imitating Song Dynasty Yaozhou ware: a potter’s perspective’, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 99–101.
Anhegger, R. (1941) ‘Quellen zur osmanischen keramik’, in Otto-Dorn, K. Das Islamische Isnik, Berlin, pp. 165–195.
Arnold, D.E. (1985) Ceramic Theory and Cultural Process, Cambridge: Cambridge University Press.
Aslanapa, O. (1969) ‘Pottery and kilns from the Iznik excavations’, in Forsuchungen zur Kunst Asiens. In Memoriam Kurt Erdmann, Istanbul: Istanbul University.
Atasoy, N. and Raby, J. (1989) Iznik the pottery of Ottoman Turkey, London: Alexandria Press.
Balfet, H., Fauvet-Berthelot, M.-F. and Monzon, S. (1983) Pour la normalisation de la description des poteries, Paris: CNRS.
Bedwin, O. and Holgate, R. (1985) ‘Excavations at Copse Farm, Oving, West Sussex’, Proceedings of the Prehistoric Society 51: 220–228.
Birchall, A. (1965) ‘The Aylesford-Swarling culture: the problems of the Belgae reconsidered’, Proceedings of the Prehistoric Society 31: 241–367.
Bishop, R.L. (1992) ‘Comments on Section II: variation’, in H. Neff (ed.), Chemical Characterization of Ceramic Pastes in Archaeology, Monographs in World Archaeology no. 7, Madison: Prehistory Press, pp. 167–170.
Blinkhom, P.W. (1993) ‘Early and Middle Saxon Pottery from Pennyland and Hartigans’, in R.J. Williams (ed.), Pennyland and Hartigans. Two Iron Age and Saxon Sites in Milton Keynes, Buckinghamshire Archaeology Monograph Series 4.
Blinkhom, P.W. (1997) ‘Habitus, social identity and Anglo-Saxon pottery’, in C.C. Cumberpatch and P.W. Blinkhorn (eds), Not So Much a Pot, More a Way of Life, Oxbow Monograph 83, Oxford: Oxbow Books, pp. 113–124.
Bradley, R. (1975) ‘Salt and settlements in the Hampshire Sussex Borderland’, in K.W. de Brisay, and K.A. Evans, (eds), Salt – The Study of an Ancient Industry, Colchester: The Colchester Archaeological Group, pp. 20―25.
Bradley, R. (1984) The Social Foundations of Prehistoric Europe, London: Longman.
Bradley, R. (1992) ‘Roman salt production in Chichester Harbour: rescue excavations at Chidham, West Sussex’, Britannia 23: 27–44.
Brisbane, M. (1981) ‘Incipient markets for early Anglo-Saxon ceramics: variations in levels and modes of production’, in H. Howard and E.L. Morris (eds), Production and Distribution: A Ceramic Viewpoint, British Archaeological Reports, International Series 120, Oxford: British Archaeological Reports, pp. 229–242.
Briscoe, T. (1981) ‘Anglo-Saxon pot stamps’, in D. Brown, J. Campbell and S. Chadwick-Hawkes (eds), Anglo-Saxon Studies 2, Oxford: British Archaeological Reports, pp. 1–36.
Brownell, W.E. (1949) ‘Fundamental factors influencing efforescence of clay products’, Journal of the American Ceramic Society 32, 12: 375–389.
Bulleid, A, and Gray, H. St G. (1948) The Meare Lake Village, vol. 1, Taunton: privately printed.
Campbell, J. (1982) ‘The lost centuries: 400–600’, in J. Campbell (ed.), The Anglo-Saxons, London: Phaidon, pp. 20–44.
Cardew, M. (1969) Pioneer Pottery, New York: St Martin’s Press.
Carswell, J. (1982) ‘Ceramics’ in Y. Petsopoulos (ed.) Tulips, arabesques and turbans. Decorative Arts from the Ottoman Empire, London: 73–96.
Carswell, J. and Dowsett, C.J.F. (1972) Kütahya Tiles and Pottery from the Armenian Cathedral of St. James, Jerusalem, 2 vols, Oxford: Oxford University Press.
Chen Tiemei, George (Rip) Rapp, Jr and Zhichun Jing (1999) ‘Provenance studies of the earliest Chinese proto-porcelain using instrumental neutron activation analysis’, in J. Henderson, H. Neff and Th. Rehren (eds), Proceedings of the International Symposium on Archaeometry, University of Illinois at Urbana Champaign (UIUC), Urbana, Illinois, 20–24 May 1996, Journal of Archaeological Science 26,8: 1003–1016.
Cherry, J. (1991) ‘Pottery and tile’, in J. Blair and N. Ramsey (eds), English Medieval Industries, London: The Hambledon Press, pp. 189–209.
Cockle, H. (1981) ‘Pottery manufacture in Roman Egypt. A new papyrus’, Journal of Roman Studies LXXI: 87–97.
Coles, J.M. (1987) Meare Village East, Somerset Levels Papers 13, Somerset Levels Project.
Collis, J.R (1979) ‘City and state in pre-Roman Britain’, in B.C. Burnham and H.B. Johnson (eds), Invasion and Response, The Case of Roman Britain, British Archaeological Reports 73, Oxford: British Archaeological Reports, pp. 231–243.
Collis, J.R (1982) ‘Gradual growth and sudden change – urbanisation in Temperate Europe’, in C. Renfrew and S. Shennan (eds), Ranking, Resource and Exchange, Aspects of the Archaeology of Early European Society, Cambridge: Cambridge University Press, pp. 73–78.
Collis, J.R (1984) Oppida, Earliest Towns North of the Alps, Sheffield: Department of Archaeology and Prehistory.
Cooper, J. (1982) ‘The research potential of molluscan shell in shell-tempered pottery’, in A. Middleton, I. Freestone, C. Johns and T. Potter (eds), Current Research in Ceramics: Thin-section Studies, British Museum Occasional Paper 32, London: British Museum Publications, pp. 161–162.
Crummy, P. (1980) ‘Camulodunum’, Current Archaeology 7: 6–10.
Cunliffe, B. (1987) Hengistbury Head Dorset. Volume 1: The Prehistoric and Roman Settlement, 3500 bc—ad 500, Oxford University Committee for Archaeology, Monograph no. 13.
Cunliffe, B. (1991) Iron Age Communities in Britain, London: Routledge and Kegan Paul, 3rd edn.
Cunliffe, B. (1995) Danebury Volume 6: A Hillfort Community in Perspective, Council for British Archaeology Research Report 102, York: Council for British Archaeology.
Dal, P.H. and Berden, W.J. (1965) ‘Bound water on clay’, Science of Ceramics 2: 59.
Daicoviciu, I. and Daicoviciu, H. (1963) Sarmizegethusa, Bucharest.
Dawson, M. (1988) ‘Excavations at Ursula Taylor Lower School’, Bedfordshire Archaeology 18: 6–24.
Deer, W.A., Howie, RA. and Zussman, J. (1962) Rock-forming Minerals V: Non-silicates, London: Longman.
Dunham, A.C. (1992) ‘Developments in industrial mineralogy: I. The mineralogy of brick-making’, Proceedings of the Yorkshire Geological Society 49, 2: 95–104.
Elsdon, S.M. (1992) ‘The Iron Age pottery in P. Clay (ed.), ‘An Iron Age farmstead at Grove Farm, Enderby, Leicestershire’, Transactions of the Leicestershire Archaeological and Historical Society 66: 83–91.
Elsdon, S.M. (1997) Old Sleaford Revealed, Oxbow Monograph 78, Oxford: Oxbow Books.
Farley, M. (1983) ‘A mirror burial at Dorton, Bucks.’, Proceedings of the Prehistoric Society 49: 269–302.
Fawn, A.J., Evans, K.A., McMaster, I. and Davies, G.M.R. (1990) The Red Hills of Essex. Salt-making in Antiquity, Colchester: Colchester Archaeology Group.
Figueral, I. (1992) ‘The charcoals’, in M.G. Fulford and J.R.L. Allen (eds), ‘Iron-making at the Chesters villa, Woolaston, Gloucestershire: Survey and Excavation 1987–91’, Britannia 23, 1: 59–215.
Foster, J. (1980) The Iron Age Moulds of Gussage All Saints, British Museum Occasional Paper no. 12, London: British Museum Publications.
Foster, J. (1995) ‘Metalworking in the British Iron Age: the evidence from Wesley Avenue, Grimsby’, in J. Raftery (ed.), Sites and Sights of the Iron Age, Essays on Field work and Museum Research presented to Ian Mathieson Stead, Oxbow Monographs 56, Oxford, Oxbow Books; London: Council for British Archaeology Research, pp. 49–61.
Freestone, I.C. (1991) ‘Technical examination of Neo-Assyrian glazed wall plaques’, Iraq 53: 55–58.
Freestone, I.C. (1999) ‘The science of early English porcelain’, Proceedings of the Sixth Conference and Exhibition of the European Ceramic Society, 20–24 June 1999, Brighton, British Ceramic Proceedings no. 60, Abstracts vol. 1: 11–17.
Freestone, I.C. and Gaimster, D. (eds) (1997) Pottery in the Making, London: British Museum Press.
Fulford, M. (1987) ‘Calleva atribatum: an interim report on the excavations of the oppidum’, Proceedings of the Prehistoric Society 53: 271–278.
Gibson, A. and Wood, A. (1997) Prehistoric Pottery for the Archaeologists, Leicester: Leicester University Press.
Glick, D.P. (1936) ‘The microbiology of ageing clays’, Journal of the American Ceramic Society 19: 169–175.
Goffer, Z. (1980) Archaeological Chemistry, New York: Wiley.
Gray, H. St G. (1966) The Meare Lake Village, vol. Ill, M.A. Cotton (ed.), Taunton: privately printed.
Gray, H. St G. and Bulleid, A. (1953) The Meare Lake Village, vol. II, Taunton: privately printed.
Grim, R.E. (1968) Clay Mineralogy, 2nd edn, New York: McGraw-Hill.
Guo Yangi (1987) ‘Raw materials for making porcelain and the characteristics of porcelain wares in north and south China’, Archaeometry 29: 3–20.
Guo Yangi and Li Guozhen (1986) ‘Song Dynasty Ru and Yaozhou green glazed wares’, in Scientific and Technological Insights on Ancient Chinese Pottery and Porcelain, Proceedings of the International Conference on Ancient Chinese Pottery and Porcelain, Shanghai Institute of Ceramics, Beijing: Science Press, pp. 153–160.
Guo Yangi, Zhang Zhigang, Chen Shiping and Zuo Zhezxi (1995) ‘Ancient ceramic moulds of Yaozhou kiln, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 320–324.
Haith, C. (1997) ‘Pottery in Early Anglo-Saxon England’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 146–151.
Hamerow, H. (1993) Excavations at Mucking, volume 2: The Anglo-Saxon Settlement, English Heritage Archaeological Report 21.
Hamerow, H., Hollevoet, Y. and Vince, A. (1994) ‘Migration period settlements and Anglo-Saxon pottery from Flanders’, Medieval Archaeology 38: 1–18.
Hamilton, S. (1985) ‘Iron Age pottery’, in O. Bedwin and R. Holgate ‘Excavations at Copse Farm, Oving, West Sussex’, Proceedings of the Prehistoric Society 51: 220–228.
Harris, V. (1997) ‘Jomon Pottery in Ancient Japan’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 20–25.
Haselgrove, C.C. (1986) ‘Central places in British Iron Age: a review and some problems’, in E. Grant (ed.) Central Places, archaeology and history, Sheffield: J.R. Collis Publications, pp. 3–12.
Hay, R.L. (1960) ‘Rate of clay formation and mineral alteration in a 4000-year-old volcanic ash soil on St. Vincent, B.W.I’, American Journal of Science 258: 354–368.
Hedges, R.E.M. (1982) ‘Early glazed pottery and faience in Mesopotamia’, in T.A. Wertime and S.E Wertime (eds), Early Pyrotechnology, Washington, DC: Smithsonian Institution Press, pp. 93—104.
Hedges, R.E.M. and Moorey, P.R.S. (1982) ‘Pre-Islamic ceramic glazes at Kish and Nineveh in Iraq’, Archaeometry 17, 1: 25–43.
Henderson, J. (1984) ‘Beads of glass’, in B.W. Cunliffe Danebury, an Iron Age Hillfort in Hampshire, volume 2: The Excavations 1969–1978: The Finds, Council for British Archaeology Research Report no. 52, London: Council for British Archaeology, pp. 396–398.
Henderson, J. (1985) ‘The raw materials of early glass production’, Oxford Journal of Archaeology 4 (3): 267–291.
Henderson, J. (ed.) (1989a) Scientific Analysis in Archaeology and its interpretation, Oxford University Committee for Archaeology Monograph no. 19; UCLA Institute of Archaeology, Archaeological Research Tools 5, Oxford: Oxford University Committee on Archaeology; Los Angeles: UCLA Institute of Archaeology.
Henderson, J. (1989b) ‘Iznik ceramics: a technical examination’ and ‘A technical examination of Ottoman ceramics’, in N. Atasoy and J. Raby, Iznik. The Pottery of Ottoman Turkey, London: Alexandria Press, Chapter 6.
Henderson, J. (1991) ‘Industrial Specialization in late Iron Age Britain and Europe’, The Archaeological Journal 148: 104–148.
Henderson, J. and Raby, J. (1989) ‘The technology of fifteenth-century Turkish tiles: an interim statement on the origins of the Iznik industry’, World Archaeology 21 (1), 115–132
Henderson, J., Challis, K., Cumberpatch, C., Larson, S. and Towle, A. (forthcoming) ‘Excavations at al-Raqqa, 1998’.
Henrickson, R.C. and Blackman, M.J. (1992) ‘Scale and paste: investigating the production of Godin III painted buff ware’, in H. Neff (ed.), Chemical Characterization of Ceramic Pastes in Archaeology, Monographs in World Archaeology no. 7, Madison: Prehistory Press, pp. 125–144.
Hodson, E.R. (1995) ‘A Münsingen Fibula, in Raftery (ed.), Sites and Sights of the Iron Age, Essays on Field work and Museum Research presented to Ian Mathieson Stead, Oxbow Monographs 56, Oxford, Oxbow Books; London: Council for British Archaeology Research, pp. 62–66.
Hurst, D. and Freestone, I.C. (1996) ‘Lead glazing technique from a medieval kiln site at Hanley Swan, Worcestershire’, Medieval Ceramics 20: 13–18.
Hurst, J.D. (ed.) (1997) A Multi-period Salt Production Site at Droitwich: Excavations at Upwich, Council for British Archaeology Research Report 107, York: Council for British Archaeology.
Institute of Archaeology – Shaanxi province (1992) Tang Dynasty Huangbao Kiln Site, vol. 1, Beijing: Cultural Relics Publishing House.
Institute of Archaeology – Shaanxi province (1997) Five Dynasties Huangbao Kiln Site, Beijing: Cultural Relics Publishing House.
Institute of Archaeology – Shaanxi province and Yaozhou Kiln Museum (1998) Song Dynasty Yaozhou Kiln Site, Beijing: Cultural Relics Publishing House.
Jacobi, G. (1974) Werkzeug und Gerät aus dem oppidum von Manching, Die Ausgrabungen in Manching, vol. 5, Wiesbaden: Steiner.
Johnson, A.L. and Norton, F.H. (1941) ‘Fundamental study of clay. 2. Mechanism of deflocculation in the clay-water system’, Journal of the American Ceramic Society 24, 6: 189–203.
Johnson, S.M., Pask, J.A. and Moya, J.S. (1982) ‘Influence of impurities in high-temperature reactions of kaolinite’, Journal of the American Ceramic Society 65, 1: 31–35.
José-Yacaman, M., Rendon, L., Arenas, J. and Serra Puche, M.C. (1996) ‘Maya blue paint: an ancient nanostructural material’, Science 273: 223–225.
Kilikoglou, V., Vekinis, G., Maniatis, Y. and Day, P.M. (1998) ‘Mechanical performance of quartz-tempered ceramics: Part I, Strength and toughness’, Archaeometry 40,1: 261–280.
Kingery, W.D. (1986) ‘The development of European porcelain’, in W.D. Kingery (ed.), High Technology Ceramics Past, Present and Future, Ceramics and Civilisation vol. III, Westerville, Ohio: The American Ceramic Society, pp. 153–180.
Kingery, W.D. (1993) ‘Painterly maiolica of the Italian Renaissance’, Technology and Culture: 28–48.
Kingery, W.D., Bowan, H.K. and Uhlmann, D.R. (1976) Introduction to Ceramics, 2nd edn, New York: John Wiley.
Kingery, W.D. and Francl, J. (1954) ‘Fundamental study of clay. 13. Drying behaviour and plastic properties’, Journal of the American Ceramic Society 37, 12: 596–602.
Kingery, W.D. and Smith, D. (1985) ‘The development of European soft-paste (frit) porcelain, in W.D. Kingery (ed.), Ancient Technology to Modern Science, Ceramics and Civilisation vol. 1, Columbus, Ohio: American Ceramic Society, pp. 273–293.
Kingery, W.D. and Vandiver, P.B. (1986) Ceramic Masterpieces, New York: The Free Press.
Knight, D. (1992) ‘Excavations of an Iron Age settlement at Gamston, Nottinghamshire’, Transactions of the Thornton Society of Nottinghamshire 96: 16–90.
Knight, D. (1999) ‘A regional ceramic sequence: pottery of the first millennium BC between the Humber and the Nene’, in J.D. Hill and A. Woodward (eds), Prehistoric Britain: The Ceramic Basis, Oxford: Oxbow Books.
Knight, D. (1999a) ‘Iron Age Briquetage and Miscellaneous Fired Clay’, p. 137 in L. Elliott and D. Knight ‘An early Mesolithic site and first millenium BC settlement and pit alignments at Swarkestone Lowes, Derbyshire’, Derbyshire Archaeological Journal 119: 79–153.
Ko Choo, C.K., Kim, S., Kang, H.T., Do, J.Y., Lee, Y.E. and Kim, G.H. (1999) ‘A comparative scientific study of the earliest kiln sites of Koryö celadon’, Archaeometry 41, 1: 51–70.
Kolb, C.C. (1989) ‘Ceramic ecology in retrospect: a critical review of methodology and results’, in C.C. Kolb (ed.), Ceramic Ecology in Retrospect, 1988: Current Research in Ceramic Materials, British Archaeological Reports International Series 513, Oxford: British Archaeological Reports, pp. 261—375.
Krämer, W. and Schubert, F. (1970) Die Ausgrabungen in Manching 1955–1961. Einfuhrumg und Fundstellungübersicht, Wiesbaden: Steiner.
Lane, T. (1992) ‘Iron Age and Roman Salterns in the South-Western Fens’, in P.P. Hayes and T.W. Lane (eds), The Fenland Project Number 5: Lincolnshire Survey, The South-West Fens, East Anglian Archaeology Report no. 55, pp. 218–229.
Leach, B. (1976) A Potter’s Book, London: Faber and Faber.
Li Gouzhen and Guan Peiying (1979) ‘Research on Yaozhou blue-green ware’, Silicate Study Journal 7, 4: 192–197.
Li Gouzhen, Guan Peiying, Wang Jian, Li Wenchao, Qin Jianwu, Zhuang Youqing and Meng Shufeng (1992) ‘Discussion of the technology on Yaozhou ware glaze of successive Dynasties’, in Li Jiazhi and Chen Xianqiu (eds), Science and Technology of Ancient Ceramics, Proceedings of the 1989 International Symposium, Shanghai: Shanghai Science and Technology Press, pp. 285–293.
Li Jianzhi (1985) ‘The evolution of Chinese pottery and porcelain technology’, in W.D. Kingery (ed.) Ancient Technology to Modern Science, Ceramics and Civilisation vol. 1, Columbus, Ohio: American Ceramic Society, pp. 135–162.
Li Wenchao, Wang Jian and Li Guozhen (1992) ‘Mechanism on formation of transition layer in ancient ceramics of Jun, Ru and Yaozhou wares in the Song Dynasty’, in Science and Technology of Ancient Ceramics, Proceedings of the 1992 International Symposium, pp. 280–285.
Magetti, M. (1982) ‘Phase analysis and its significance for technology and origin, in J.S. Olin and A.D. Franklin (eds), Archaeological Ceramics, Washington, DC: Smithsonian Institution Press, pp. 121–133.
Magrill, P. and Middleton, A. (1997) ‘A Canaanite potter’s Workshop in Palestine’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 68–73.
Mason, R.B. and Tite, M.S. (1994) ‘The beginnings of Islamic stonepaste technology’, Archaeometry 36: 77–92.
Mason, R.B. and Tite, M.S. (1997) ‘The beginnings of tin-opacification of pottery glazes’, Archaeometry 39, 1: 41–58.
Matson, F.R. (1965) Ceramics and Man, London: Methuen.
Matson, F.R. (1971) ‘A study of temperatures used in firing ancient Mesopotamian pottery’, in R.H. Brill (ed.), Science and Archaeology, Cambridge: MIT Press, pp. 65–80.
Matson, F.R. (1986) ‘Glazed brick from Babylon – historical setting and microprobe analyses’, in W.D. Kingery (ed.), Technology and Style, Ceramics and Civilisation II, Columbus, Ohio: American Ceramic Society, pp. 133–156.
May, J. (1996) Dragonby. Report on Excavations at an Iron Age and Romano-British Settlement in North Lincolnshire, Oxbow Monograph 61, Oxford: Oxbow Books.
Medley, M. (1986) The Chinese Potter – A Practical History of Chinese Ceramics, Ithaca, New York: Cornell University Press.
Mehren, F., Muller, K.A. and Fitzpatrick, W.J. (1981) ‘Characterization of particle orientations in ceramics by electron paramagnetic resonance’, Journal of the American Ceramic Society 64, 10: CI29–C130.
Middleton, A. (1996) ‘Petrology’, in J. May (ed.), Dragonby. Report on Excavations at an Iron Age and Romano-British Settlement in North Lincolnshire, Oxbow Monograph 61, Oxford: Oxbow Books, pp. 419–421.
Millett, M. (1990) The Romanization of Britain, Cambridge: Cambridge University Press.
Moorey, P.R.S. (1994) Ancient Mesopotamian Materials and Industries. The Archaeological Evidence, Oxford: The Clarendon Press.
Morris, E.L. (1981) ‘Ceramic exchange in western Britain: a preliminary view’, in H. Howard and E. Morris (eds), Production and Distribution: A Ceramic Viewpoint, Oxford: British Archaeological Reports 120, pp. 67–81.
Morris, E.L. (1982) ‘Iron Age pottery from western Britain: another petrological study’, in I.C. Freestone, C. Johns and T. Potter (eds), Current Research in Ceramics: Thin-Section Studies, London: British Museum Occasional Paper 32, pp. 15–27.
Morris, E.L. (1983) ‘Petrological report, Droitwich briquetage containers, seriation analysis by fabric type of the Iron Age pottery’, in A. Saville and A. Ellison (eds), Excavations at Uley Bury Hillfort Gloucestershire 976, Bristol: Western Archaeological Trust Excavations Monograph 5.
Morris, E.L. (1985) ‘Prehistoric salt distributions: two case studies from western Britain’, Bulletin of the Board of Celtic Studies 32, 336–379.
Morris, E.L. (1991) ‘The pottery’, in P. Barker, R. Haldon and E. Jenks, Excavations on Sharpstones Hill near Shrewsbury 1965–71, in M.O.H. Carver (ed.), Prehistory in Lowland Shropshire, Transactions of the Shropshire Archaeological Society 67, 15–57.
Morris, E.L. (1994a) ‘Production and distribution of pottery and salt in Iron Age Britain: a review’, Proceedings of the Prehistoric Society 60, 371–393.
Morris, E.L. (1994b) ‘The organisation of salt production and distribution in Iron Age Wessex’, in A.P. Fitzpatrick and E.L. Morris (eds), The Iron Age in Wessex: Recent Work, Salisbury: The Trust for Wessex Archaeology, pp. 14–16.
Myers, E.J. (1992) ‘Compositional standardization in sixteenth-century Italian maiolica’, in H. Neff (ed.), Chemical Characterization of Ceramic Pastes in Archaeology, Monographs in World Archaeology no. 7, Madison: Prehistory Press, pp. 145–157.
Myres, J.N.L. (1969) Anglo-Saxon Pottery and the Settlement of England, Cambridge: Cambridge University Press.
Myres, J.N.L. (1977) A Corpus of Anglo-Saxon Pottery of the Pagan Period, 2 vols, Cambridge: Cambridge University Press.
National Academy of Sciences (1980) Firewood Crops: Shrub and Tree Species for Energy Production, Washington, DC: National Academy of Sciences.
Newell, R.W. (1995) ‘Some notes on “splashed glazes’”, Medieval Ceramics 19: 77–88.
Nicklin, K. (1981a) ‘Ceramic pyrometry: two Ibibio examples’, in H. Howard and E. Morris (eds), Production and Distribution: A Ceramic Viewpoint, British Archaeological Reports, International Series 120, Oxford: British Archaeological Reports, pp. 347–359.
Nicklin, K. (1981b) ‘Pottery production and distribution in southeast Nigeria’, in H. Howard and E. Morris (eds), Production and Distribution: A Ceramic Viewpoint, British Archaeological Reports, International Series 120, Oxford: British Archaeological Reports, pp. 169–196.
Nissen, H.J. (1988) The Early History of the Ancient Near East, Chicago: University of Chicago Press.
Norton, E.H. (1970) Fine Ceramics, Technology and Applications, New York: McGraw-Hill.
Norton, E.H. and Johnson, A.L. (1944) ‘Fundamental study of clay. 5. Nature of the water film in a plastic clay, Journal of the American Ceramic Society 27, 3: 77–80.
Oates, D. and Oates, J. (1976) The Rise of Civilization, Oxford: Oxford University Press.
O’Brien, J., Holland, T.D., Hoard, R.J. and Fox, G.L. (1994) ‘Fracture toughness determinations of alumina using four-point-bend specimens with straight-through and chevron-notches’, Journal of the American Ceramic Society 63: 300–305.
Partridge, C. (1981) Skeleton Green: A Late Iron Age and Romano-British Site, London: Britannia Monographs 2.
Peacock, D.P.S. (1968) ‘A petrological study of certain Iron Age pottery from western England’, Proceedings of the Prehistoric Society 34: 414—427.
Peacock, D.P.S. (1969) ‘A contribution to the study of Glastonbury Ware from south-western Britain’, The Antiquaries Journal 49: 41–61.
Peacock, D.P.S. (1982) Pottery in the Roman World, London: Longman.
Peltenburg, E. (1971) ‘Some early developments of vitreous materials’, World Archaeology 3, 1: 6—12.
Piccolpasso, C. (1980) The Three Books of the Potter’s Art: A Facsimile of the Manuscript in the Victoria and Albert Museum, (R. Lightbown and A. Caiger-Smith, eds), 2 vols., London: Scolar Press.
Pieta, K. (1982) Die Puchov-Kultur, Studia Archaeologica Slovaca, Institūti Archaeologici Academiae Scientiarum Slovacae, 1, Nitra: Academiae.
Piggott, S. (1965) Ancient Europe, Edinburgh: Edinburgh University Press.
Pleiner, R. (1977) ‘Neue Grabungen frühgeschichtlicher Eisenhüttenplatte in der Tschechoslowakei und die Bedeutung des Schachtofens fur die Entwicklung des Schmelzvorganges’, in A. Ohrenberger and K. Kaus (eds), Archäologische Eisenforschung in Europa, Graz: Burgenalandisches Landesmuseum, pp. 107–117.
Pleiner, R. (1980) ‘Early iron metallurgy in Europe’, in T.A. Wertime and J.D. Muhly (eds), The Coming of the Age of Iron, Yale: Yale University Press, pp. 375–415.
Plog, F. (1977) ‘Modelling economic change’, in T.K. Earle and J.E. Ericson (eds), Exchange Systems in Prehistory, New York: Academic Press, pp. 127–140.
Pollard, A.M. and Hatcher, H. (1994) ‘The chemical analysis of oriental ceramic body compositions, part 1: wares from north China’, Archaeometry 36: 41–62.
Pollard, A.M., Hatcher, H. and Heron, C. (1996) Archaeological Chemistry, Cambridge: The Royal Society of Chemistry.
Portal, J. (1997) ‘Korean Celadons of the Koryo Dynasty’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 98–103.
Postgate, J.N. and Moon, J.A. (1982) ‘Excavations at Abu Salabikh 1981’, Iraq 44: 103–136.
Ralston, I. (1988) ‘Central Gaul at the Roman Conquest: conceptions and misconceptions’, Antiquity 62: 786–794.
Renfrew, C. (1975) ‘Trade and action at a distance: questions of integration and communication’, in J. Sabloff and C.C. Lamberg-Karlovsky (eds), Ancient Civilization and Trade, Albuquerque: University of New Mexico Press, pp. 3–59.
Rhodes, D. (1969) Kilns: Design, Construction and Operation, Philadelphia: Chilton Books.
Rice, P.M. (1987) Pottery Analysis: A Sourcebook, Chicago: The University of Chicago Press.
Rigby, V. and Freestone, I.C. (1985) ‘The petrology and typology of the earliest identified central Gaulish imports’, Journal of Roman Pottery Studies 1: 6–21.
Rigby, V. and Freestone, I.C. (1997) ‘Ceramic changes in late Iron Age Britain’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 56–61.
Roberts, P. (1997) ‘Mass production of Roman finewares’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 188–193.
Rodwell, W.J. (1976) ‘Coinage, oppida and the rise of Belgic power in south-eastern Britain’, in B. Cunliffe and T. Rowley (eds), Oppida: The Beginnings of Urbanism in Barbarian Europe, British Archaeological Reports, Supplementary Series 11, Oxford: British Archaeological Reports, pp. 181–187.
Russel, A.D. (1985) ‘Petrological report on the West Stow Saxon Pottery’, in S.E. West (ed.), West Stow: The Anglo-Saxon Village, 2 vols, East Anglian Archaeology, vol. 24.
Ryan, W. (1965) ‘Factors influencing the dry strength of clays and bodies’, Transactions of the British Ceramic Society 64: 275–285.
Rye, O.S. (1976) ‘Keeping your temper under control’, Archaeology and Physical Anthropology in Oceania 11, 2: 106–137.
Rye, O.S. and Evans, C. (1976) Traditional Pottery Techniques of Pakistan: Field and Laboratory Studies, Smithsonian Contributions to Anthropology no. 21, Washington, DC: Smithsonian Institution Press.
Şahin, F. (1981) ‘Kütayha seramik teknolojisi ve çini firin-lari hakkinda gör¨şler’, Sanat Tarihi Yilli gi 11, 133–151.
Scherns, J.W.H. and Brill, R.H. (1984) ‘Iron and sulfur-related colours in ancient glasses’, Archaeometry 26, 2: 199–209.
Sellwood, L. (1984) ‘Tribal boundaries viewed from the perspective of numismatic evidence’, in B. Cunliffe and D. Miles (eds), Aspects of the Iron Age in Central Southern Britain, University of Oxford Committee for Archaeology Monograph 2, Oxford: University Committee for Archaeology, pp. 191–204.
Shepard, A.O. (1976) Ceramics for the Archaeologist, Washington, DC: Carnegie Institution of Washington.
Simpson, St J. (1997a) ‘Prehistoric ceramics in Mesopotamia’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 38–43.
Simpson, St J. (1997b) ‘Early urban ceramic industries in Mesopotamia’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 50–55.
Singer, C, Holmyard, E.J., Hall, A.R and Williams, T.J. (1956) A History of Technology, vol. II, Oxford: Clarendon.
Soontaek Choi-Bae (1984) Se ladon-Keramik der Koryo-Dynastie, Köln: Museum für Ostasiatische Kunst, pp. 918–1392.
Staehelin, W. (1965) The Book of Porcelain: The manufacture, transport, and sale of export porcelain in China during the eighteenth century, illustrated by a series of contemporary Chinese watercolours, London: Lund Humphries.
Starkey, P. (1977) Saltglaze, London: Pitman.
Stead, I.M. (1967) ‘A LaTène III burial at Welwyn Garden City’ Archaeologia 101: 1–62.
Stead, I.M. (1985) Celtic Art in Britain before the Roman Conquest, London: British Museum Publications.
Stead, I.M. and Rigby, V. (1989) Verulamium: The King Harry Lane Site, London: English Heritage Archaeological Monographs 12.
Sterner, J. (1989) ‘Who is signalling whom? Ceramic style, ethnicity and taphonomy among Sirak Bulahay’, Antiquity 63: 451–459.
Swan, V.G. (1984) The Pottery Kilns of Roman Britain, Royal Commission on Historical Monuments, Supplementary Series 5, London: Her Majesty’s Stationery Office.
Thompson, I. (1982) Grog-Tempered Belgic Pottery of South-Eastern England, Oxford: British Archaeological Reports 108.
Thompson, I. and Barfield, P. (1986) ‘Late Iron Age pottery and briquetage from Elm Park House, Ardleigh, 1981’, Essex Archaeological and Historical Society 17: 166–170.
Thornton, D. (1997) ‘Maiolica production in Renaissance Italy’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 116–121.
Tite, M.S. (1989) ‘Iznik pottery: an investigation of the methods of production’, Archaeometry 31, 2: 115–132.
Tite, M.S. (1991) ‘Technological investigations of Italian Renaissance ceramics’, in T. Wilson, (ed.), Italian Renaissance Pottery: Papers written in association with a Colloquium at the British Museum, London: British Museum Publications, pp. 280–285.
Tite, M.S. (1999) ‘Pottery production, distribution, and consumption – the contribution of the physical sciences’, Journal of Archaeological Method and Theory 6: 181–233.
Tite, M.S. and Bimson, M. (1986) ‘Faience: an investigation of the microstructures associated with the different methods of glazing’, Archaeometry 28, 1: 69–78.
Tite, M.S., Freestone, I.C., Mason, R., Molera, J., Vendrell-saz, M. and Wood, N. (1998) ‘Lead glazes in antiquity – methods of production and reasons for use’, Archaeometry 40, 2: 241–260.
Tite, M.S. and Maniatis, Y. (1975) ‘Scanning electron microscopy of fired calcareous clays’, Transactions of the British Ceramic Society 74: 19–22.
Tonghini, C. and Henderson, J. (1998) ‘An eleventh-century pottery production workshop at al-Raqqa, Preliminary report’, Levant 30: 113–127.
Van der Leeuw, S.E. (1975) ‘Medieval pottery from Haarlem: a model’, in J.G.N. Renaud (ed.), Rotterdam Papers II, Rotterdam: Coördinatie Commissie van Advies inzake Archeologisch Onderzoek binnen het Ressort, pp. 67–87.
Vandiver, P.B, Cort, L.A. and Handwerker, C.A. (1989) ‘Variations in the practice of ceramic technology in different cultures: a comparison of Korean and Chinese celadon glazes’, in P.E. McGovern and M.D. Notis (eds), Cross-craft and Cross-cultural Interactions in Ceramics, Ceramics and Civilisation vol. IV, Westerville, Ohio: The American Ceramic Society, pp. 347–388.
Vandiver, P.B, Cort, L.A., Handwerker, C.A. and Kingery, W.D. (1984) ‘Composition and structures of Chinese Song Dynasty celadon glazes from Longquan’, Bulletin of the American Ceramic Society 63, 4: 612–616.
Vekinis, G. and Kilikoglou, V. (1998) ‘Mechanical performance of quartz-tempered ceramics: Part II, Hertzian strength, wear resistance and applications to ancient ceramics’, Archaeometry 40, 2: 281–292.
Velde, B. and Druc, I.C. (1999) Archaeological Ceramic Materials, Berlin: Springer.
Vince, A. (1989) ‘The petrography of Saxon and early medieval pottery in the Thames valley’, in J. Henderson (ed.), Scientific Analysis in Archaeology and its interpretation, Oxford University Committee for Archaeology Monograph no. 19; UCLA Institute of Archaeology, Archaeological Research Tools 5, Oxford: Oxford University Committee on Archaeology; Los Angeles: UCLA Institute of Archaeology, pp. 163–177.
Wang Fang and Wang Lefang (1995) ‘The manufacture technology of Yaozhou porcelain mould and its characteristics’, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 313–319.
Wang Lefang (1995) ‘Five Dynasties ceramic moulds recently discovered at Yaozhou kiln site’, Kaogu yu Wenwu (Archaeology of relics) 3: 50–55 (in Chinese).
Watson, W.M. (1986) Italian Renaissance Majolica from the William A. Clark Collection, London: Scala Books.
Welch, M. (1992) Anglo-Saxon England, London: Batsford.
Welsby, D. (1997) ‘Early pottery in the Middle Nile Valley’, in I.C. Freestone and D. Gaimster (eds), Pottery in the Making, London: British Museum Press, pp. 26–31.
West, S. (1985) West Stow: The Anglo-Saxon Village, East Anglian Archaeology 24.
White, L. (1972) ‘The act of invention’, in M. Kranzberg and W.H. Davenport (eds), Technology and Culture. An Anthology, New York: New American Library, pp. 274–291.
Whitehouse, D. (1971) ‘Excavations at Sīrāf. Fourth interim report’, Iran 9: 1–18.
Williams, D. (1992) A Note on the Petrology of some Late Iron Age Sherds from Gamston, Nottinghamshire, Ancient Monuments Laboratory Report 14/92, London: English Heritage.
Williams, D. and Vince, A. (1997) ‘The characterization and interpretation of early to middle Saxon granitic tempered pottery in England’, Medieval Archaeology XLI, 214–220.
Wilson, T. (1987) Ceramic Art of the Renaissance, London: British Museum Publications.
Wood, N. (1999) Chinese Glazes, London: Black.
Wood, N. and Freestone, I.C. (1995) ‘A preliminary examination of a Warring States pottery jar with so-called “glass paste” decoration’, in Guo Jinkum (ed.), Science and Technology of Ancient Ceramics 3; Proceedings of the International Symposium on Ancient Ceramics (ISAC 95), Shanghai, pp. 12–17.
Wood, N., Henderson, J. and Tregear, M. (1989) ‘An examination of Chinese fahua glazes’, Proceedings of the International Symposium on Ancient Ceramics (ISAC ‘89), Shanghai, pp. 172–182.
Woodiwiss, S. (ed.) (1992) Iron Age and Roman Salt Production and the Medieval Town of Droitwich, London: Council for British Archaeology Research Report 81.
Woods, A.J. (1986) ‘Form, fabric and function: some observations on the cooking pot in antiquity’, in W.D. Kingery (ed.), Technology and Style, vol. II, Columbus, Ohio: American Ceramic Society, pp. 157–172.
Woolley, C.L. (1956) Ur Excavations IV: The Early Periods, London and Philadelphia: The British Museum and University Museum.
Wright, R.P. (1986) ‘The boundaries of technology and stylistic change’, in W.D. Kingery (ed.), Technology and Style, Ceramics and Civilisation, vol. II, Columbus, Ohio: The American Ceramic Society, pp. 1–20.
Yang Zhongtang (1992) ‘Study on gas composition of ancient Yaozhou celadon glaze and its archaeological significance’, in Science and Technology of Ancient Ceramics, Proceedings of the 1992 International Symposium, pp. 201–210.
Yang Zhongtang, Li Yueqin, Wang Zhihai and Xu Peicang (1995) ‘Research on the molecular network structure in glass phases of glaze from ancient Yaozhou celadon and black-ware’, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 72–77.
Yap, C.T. and Younan Hua (1995) ‘Chinese Greenware glazes of eight famous wares: Yue, Longquan, Southern Song Guan, Ru, Linru, Jun, Yaozhou and Ge’, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 155–162.
You Enpu (1986) ‘Kiln furniture and methods of ware-setting used in Yaozhou kiln and Ding kiln’, in Scientific and Technological Insights on Ancient Chinese Pottery and Porcelain, Proceedings of the International Conference, Shanghai Institute of Ceramics, Beijing: Science Press, pp. 282–286.
Zang Zhiang, Li Jiazhi and Zuo Zhenxi (1995) ‘Study on celadon technology of Yaozhou kiln in successive dynasties’, in Science and Technology of Ancient Ceramics, Proceedings of the 1995 International Symposium, Beijing: Science Press, pp. 60–65.