Pottery technology in the Tang dynasty (ninth century ad): archaeometric analyses of a Gongyi sherd found at Siraf,Iran

In 1969–70, a single Tang dynasty blue‐spotted Gongyi sherd was found at Siraf, Iran, the main trading port on the Persian Gulf in the early Islamic period. This is the only known example of Chinese blue‐and‐white ware, whether low‐ or high‐fired, found in the Middle East from such an early date. The sherd provides direct archaeological evidence for the Indian Ocean trade between China and the Middle East in the ninth century ad . The body paste, clear glaze and blue glaze or pigment were analysed by thin‐section petrography, scanning electron microscopy with energy‐dispersive X‐ray spectrometry (SEM‐EDX) and X‐ray fluorescence (XRF). The technological analysis reveals the different steps of the chaîne opératoire: clay mixing, slip and glaze application, and decoration with the cobalt blue glaze before high‐temperature firing. These steps are characteristic of Tang stoneware production at Gongyi in Henan province, China. The use of cobalt blue pigment as part of a simple spotted decoration scheme on the Gongyi sherd, and its find context within the Middle East, provides evidence for the complex interplay and influence occurring between Chinese and Middle East ceramic industries at this time. Closely comparable examples of contemporary low‐fired earthenware ceramics with cobalt blue decoration on a white tin glaze manufactured within the Middle East also occur within the same assemblage from Siraf.     

历代耀州窑釉料渊源关系的初步分析

耀州窑是我国古代名瓷窑。为了探讨历代耀州窑釉料之间的渊源关系,用中子活化分析(NAA)技术测定古耀州瓷釉样品和耀州窑博物馆附近粘土矿样品中29种元素的含量,将这批NAA数据进行模糊聚类分析,得到动态模糊聚类分析图。结果表明：唐代的黑瓷釉原料产地非常集中,矿料成分单纯。宋代青瓷釉料配方比较稳定,五代青瓷具有承前启后的作用。金代月白釉料成分和宋代青瓷釉料接近。唐三彩蓝釉料与其他耀州瓷釉料来源明显不同。     

A Study on the Elemental Composition of Chinese Mise Type Wares from Different Periods and Kilns

A large number of porcelain shards were unearthed at the Hehuaxin and Silongkou kilns around the Shanglin Lake, Ningbo, China, some of which had clear stratification to enable the determination of the date of firing. With the purpose of studying the elemental composition in different cultural periods and between kilns, the chemical compositions of 43 typical shards from these two kilns were determined by energy‐dispersive X‐ray fluorescence (EDXRF). The results show that the mean contents of K₂O, CaO and MnO in the glaze fluctuate in different cultural periods at the Hehuaxin kiln, but not systematically. Principal component analysis (PCA) indicates that samples from the Five Dynasties and the Northern Song dynasty are similar to each other. This shows continuity in the raw materials and firing technology between the two dynasties. Comparing the mise type wares from the Hehuaxin and Silongkou kilns in the Northern Song dynasty, we found that MnO and ZrO₂ in the glaze can be used as fingerprinting elements to distinguish between samples from these two sites. In spite of this, their chemical compositions are broadly similar. Thus, perhaps, their chemical compositions can be taken as typical for those of the mise type wares produced around the Shanglin Lake.     

河南巩义窑、河北邢窑出土瓷器的原料来源研究——以北朝和隋唐时期出产的青瓷、白瓷为例

为探讨河南巩义窑、河北邢窑出土的不同时期青瓷、白瓷的原料来源,用显微观察、电子探针(EPMA)等手段,分析其原料来源及技术工艺进行分析,并探讨两窑之间的技术联系。分析可知,两窑在瓷釉、瓷胎的原料配置上存在差异:巩义窑瓷胎均使用当地高岭土一元配方,瓷釉中加入瓷胎原料为基体并加入高钙草木灰;邢窑瓷胎在使用当地高岭土的基础上加入长石类矿物原料,瓷釉中除瓷胎所使用的黏土以外,还加入含有高钙高镁的草木灰或矿物原料。两窑还存在一些共性如:两窑瓷釉均添加石英类原料以提高SiO_2含量;巩义窑与邢窑两地早期、唐中期产品形制相似,原料配方有共通之处,说明当时两地在陶瓷的原料配方、制瓷技术中有过交流。     

汝州东沟窑金元时期青瓷与钧瓷原料和工艺特征的比较研究

金元时期在豫西中部地区多个窑址同时生产青瓷和钧瓷,发掘于2005年的汝州东沟窑遗址即是该类窑址典型代表之一。为系统了解东沟窑青瓷和钧瓷的胎釉元素组成特征和工艺特点、揭示两类瓷器各自随时代变化的规律,本项研究采用EDXRF和OM对东沟窑遗址出土且地层明确的43件金、元时期青瓷与钧瓷标本胎、釉化学组成和工艺性能进行测试分析,探讨了胎、釉的原料配比、釉层厚度和胎釉反应层厚度等工艺特征随时代和标本类型的变化规律。研究结果表明:东沟窑同时期青瓷和钧瓷胎体元素组成较接近,而两者釉的元素组成差异明显,金元钧瓷釉的SiO2/Al2O3摩尔比值都明显高于同时代青瓷的相应比值,呈现钧瓷釉典型的高硅低铝组成特征。从金代到元代,东沟窑青瓷和钧瓷釉都呈现从钙釉向钙-碱釉的转变。本项研究还观察到金元钧瓷的釉层和反应层厚度均高于同时代的青瓷;而从金过渡到元,两类瓷片的釉层和反应层厚度均趋厚。本项研究对揭示金元时期豫西中部地区青瓷和钧瓷间的传承和演化关系提供了有意义的科技数据。     

CHARACTERISTIC ELEMENTS OF LONGQUAN GREENWARE

Some examples of Longquan greenware have been analysed by neutron activation analysis. Most sherds are from kiln excavations in Zhejiang province, and date from the Song, Yuan and Ming dynasties. The elements Ce, Yb, Hf and Ta are shown to be consistently high and suggest that a common clay was used over a long period. The iron content of the glaze is shown to decrease from the Song to the Ming dynasty, implying an improvement in the refiring of the glaze raw materials.     

Tracing the origin of Chinese early white porcelain in the late sixth century—evidence from Xing kiln

As the criterion used by archaeologists for determining early white porcelain is quite ambiguous, the origin of Chinese white porcelain remains a point of disagreement. In this study, we systematically investigate 61 typical Xing porcelains of the late Northern dynasties to the early Sui dynasty (550–600 CE) using spectrophotometer, X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD), and analyze the differences between early white porcelain and celadon of Xing kiln in terms of their whiteness and raw materials characteristic. The results show that early white porcelain is a new type of ware that differs from celadon, which can be distinguished by whiteness, with a whiteness greater than 8% being early white porcelain and a whiteness less than 8% being celadon. It is assumed that the ancient potters created the whiter wares based on celadon by improving the glaze and selecting new raw materials for the body, but the production of this type of ware was short lived and subsequently refined in the Sui dynasty (581–618 CE) owing to the limited improvement in whiteness.     

INCISED SLIPWARE PRODUCTION AT CASTELFIORENTINO (FLORENCE): THE ‘VIA BERTINI’ SITE (15TH–17TH CENTURIES)*

This study deals with the physical–chemical and mineralogical–petrographic investigations (OM, SEM–EDS, EPMA, ICP, XRpD, Mössbauer and IR) conducted on first‐ and second‐firing wasters belonging to two types of incised slipware (sgraffito), manufactured at Castelfiorentino between the late 15th and the early 17th centuries. Raw materials, colouring agents and firing products were analysed in order to establish the production technology of the ceramic coatings, by means of detailed microtextural and chemical investigations. The pottery underwent two firing processes: the firing of the white slip‐coated ceramic body and a further firing after application of the glaze. The homogeneity of the raw materials, white slip and glaze is remarkable, and demonstrates the use of well‐established recipes with a constant supply of raw materials from the same places. Highly efficient kiln management during both firings is revealed by body–glaze interface reactions.     

A technological study of ancient faience from Egypt

The chemical compositions and microstructures of some 35 faience objects from Egypt spanning the period from the Middle Kingdom through to the 22nd dynasty are determined using analytical scanning electron microscopy. Replicate faience beads glazed in the laboratory using the efflorescence and cementation methods are similarly investigated. In efflorescence glazing, there appears to be preferential efflorescence of soda over potash, and in cementation glazing, preferential take up of potash over soda into the glaze. These data are then used to try to infer the raw materials and methods of glazing employed in the production of the ancient faience. The glaze/glass phases present in the faience differ significantly in composition from that of New Kingdom glass. This could be due either to the use of different plant ashes or to changes in the composition of the plant ashes during the production of faience and/or glass. Although it is only rarely possible to determine with certainty whether ancient faience was glazed by efflorescence, cementation or application, the observed microstructures provide an indication of the approach adopted to achieve desired performance characteristics such as strength.     

中国古代高温铁釉瓷的呈色研究

中国是最早烧制高温陶瓷的国家,从原始瓷开始,含铁原料制作的颜色釉瓷贯穿了整个中国制瓷的历史,从而产生了呈色各异、品种繁多的铁釉瓷.为研究影响铁釉瓷呈色的各类因素,本工作综合应用成分分析方法,对一些典型的铁釉瓷品种进行定量测定.研究表明:高温铁釉中Fe2O3的含量范围从1％至高达约18％,铁的含量对釉的呈色起着决定性的作用;同时窑炉的烧成气氛和原料中的TiO2含量变化会影响Fe2+、Fe3+的生成比例,从而使釉色发生改变;另外,原料中MnO的含量、施釉工艺等也会对釉色产生影响.研究结果将对我国高温铁釉瓷制作技术的产生、发展有一个更好的诠释.     

指纹元素分析对南宋郊坛官窑的起源研究

选取30个南宋官瓷样品、2个效坛官窑的原料、紫金土和4个现代仿官瓷样品进行中子活化分析（NAA）,测定每个样品中36种微量元素的含量。从这36种元素中挑选出9种指纹元素的含量进行散布分析。结果表明：南宋官窑的釉料和胎料产地明显不同;南宋官窑有着长期稳定的釉料和胎料产地;遗址缸内的原料（35#）、练泥池内的原料（36#）、紫金土（37#）既不同于古官瓷的釉料,也不同于胎料。练泥地内的原料（36#）比较接近于胎料。现代官瓷的釉料和胎料与古官瓷的明显不同,说明它们的产地不同。     

河曲坪头遗址龙山时期陶器及其制陶原料的化学成分分析

为了对山西省忻州市河曲坪头遗址出土的龙山时期的陶器以及制陶原料中的粘土原料的种类和来源进行相关探讨,利用ICP-OES对出土的陶器、坯料,以及遗址附近采集的土样进行了化学成分测试,并使用SPSS软件对分析结果进行了降维处理和主成分分析。结果显示:坪头遗址不同质地的陶器陶土原料相同,只是在钙含量方面存在细微差异。制作陶器所用的粘土原料很可能取自附近的红色古土壤层。该遗址是古人在当地制作陶器的一个场所。     

Chemical and strontium isotope analysis of Yaozhou celadon glaze

To produce useful information about the raw materials used in northern Chinese Yaozhou celadon glazes Chinese glazes (especially the source of the calcium‐bearing flux), Sr isotope analysis has been used for the first time. Yaozhou celadon is one of the most important representatives of northern Chinese greenware. The study has enhanced our understanding of the raw material sources used to make Yaozhou glazes dating from the Tang to Northern Song dynasties. It is highly likely that ‘Fuping stone’ mentioned in the historical record is not the main raw material used to make Yaozhou celadon glazes of the Tang to Northern Song dynasties. The results of ⁸⁷Sr/⁸⁶Sr analysis of the Yaozhou celadon glazes studied produce relatively consistent ⁸⁷Sr/⁸⁶Sr isotopic signatures, with a wide variation of relatively high Sr concentrations. This is firm evidence that a calcium‐bearing plant ash was the source of the calcium and of the flux in the Celedon glazes studied, and not, as some have suggested, limestone or ‘Liaojiang stone’. The study had illustrated that the present approach has great potential in providing a new way of reconstructing porcelain glaze technology.     

The production technology of Iznik pottery—a reassessment*

Previous research has established that Iznik pottery differs from other Islamic stonepaste pottery in that its stonepaste bodies contain lead oxide as well as soda and lime, and that a significant proportion of the tin oxide in its glaze is present in solution rather than as tin oxide particles. In order to better understand these distinguishing features, the chemical compositions and microstructures of Iznik pottery and tile samples, together with those of lumps of glass found in association, were investigated using both scanning electron and optical microscopy. These data have been supplemented by the study of replicate lead–alkali glazes produced in the laboratory with a range of different compositions. The results demonstrate that separate soda–lime and high‐lead glasses were used in the production of Iznik stonepaste bodies, and that the total glass contents of the bodies were significantly higher than those quoted by Abū’l‐Qāsim, who was writing in about ad 1300. The very high purity of the lead–soda Iznik glazes indicated that the alkali flux used was either a purified plant ash or an as yet unidentified mineral source of soda. Replication experiments established that the high solubility of tin oxide in the glaze was due to the high purity of the glaze constituents. Furthermore, it is suggested that tin oxide was added to the glaze in order to give it a very slight opacity and thus obscure any blemishes in the underlying body.     

汝官瓷和钧官瓷主量化学组成的多元统计分析

为了研究多种釉色汝官瓷和钧官瓷的原料来源、成分和分类关系,正确鉴别两窑瓷器,应用质子激发X荧光分析(PIXE)技术测定了一组清凉寺窑汝官瓷片和一组钧台窑钧官瓷片的主量化学组成,应用多元统计分析方法对测试数据进行了分析,结果表明:多数汝官瓷胎、钧官瓷胎样品的原料产地和成分接近但有所不同;汝官瓷釉和钧官瓷釉的原料产地和配方则明显不同;从主量化学组成上可以较好地区分汝官瓷釉和钧官瓷釉样品。分析结果可为深入研究汝官瓷和钩官瓷的原料产地、起源关系、真伪鉴别和提高仿古瓷器的质量等方面提供可借鉴的科学依据。     

景德镇明代洪武瓷的化学组成研究

明代洪武时期,景德镇开始设立御窑烧造宫廷用瓷,因此,对这批洪武瓷的研究一直是人们关注的问题。采用能量色散X荧光分析方法对景德镇和南京出土的数件洪武瓷样品作胎釉成分无损测试。结果表明,明洪武不同品种瓷器采用的釉料不同;官窑洪武青花瓷和蓝釉瓷的色料采用了低锰高铁特征的钴料;洪武瓷胎料使用了二元配方。     

Study on the Material and Manufacturing Technology of Different Types of Longquan Ware Imitations from Dapu Kiln of Guangdong Province in the Ming Dynasty of China (ad 1368–1644)

Research on ancient Longquan wares and their imitations has attracted considerable attention. Using a series of experimental methods, including micro X‐ray fluorescence spectroscopy (μ‐XRF), X‐ray diffractometry (XRD), optical microscopy (OM), polarizing microscopy (PLM), dilatometry (DIL) and spectrophotometery, different samples of Longquan imitations from Dapu in Guangdong Province were collected and analysed. The study of different types of celadon from the Dapu kiln factories shows that the pale yellow body had a higher TFe₂O₃ content, and the body material must therefore have been treated differently or have come from a different source. The SiO₂ and Al₂O₃ contents in the body can be used as auxiliary parameters to identify Longquan wares and its imitations. The study also found that both kinds of glaze recipe—including calcium–alkali glaze and alkali–calcium glaze—existed in the Dapu products, which suggested that while imitating Longquan ware, the potters in Dapu also showed innovation in the recipe for the glaze material. Moreover, there were some differences in the TFe₂O₃ content, as well as the size, number and distribution of bubbles in the different types of glaze. Finally, the study revealed that the material of both the saggars and separators were composed of another porcelain clay, different from that of the celadon body. In addition, the white and compact body of the celadon had a higher firing temperature, of 1140–1187 °C, compared with other types of wares, which had a lower firing temperature of 1050–1080 °C.     

中国孔雀蓝釉器物的产生及其原因探讨

孔雀蓝釉在中国唐代已能够自己生产,并使用于建筑之上;孔雀蓝釉器物在中国出现于宋代,金代中期即１２世纪晚期开始连续生产,目前发现山西地区是主要产地之一,而且直接影响到后来山西出现的法花釉,它与中亚、西亚的孔雀蓝釉有一定的渊源关系,它的发展与道教有某种程度的联系。     

ICP-MS trace element analysis of Song dynasty porcelains from Ding,Jiexiu and Guantai kilns,north China

Bodies of Ding kiln white porcelains and their imitations from Guantai and Jiexiu kilns of the Chinese Song dynasty (960–1279 AD) were analysed for 40 trace elements by inductively coupled plasma mass spectrometry (ICP-MS). Numerous trace element compositions and ratios allow these visually similar products to be distinguished, and a Ding-style shard of uncertain origin is identified as a likely genuine Ding product. In Jiexiu kiln, Ding-style products have trace element features distinctive from blackwares of an inferior quality intended for the lower end market. Based on geochemical behaviour of these trace elements, we propose that geochemically distinctive raw materials were used for Ding-style products of a higher quality, which possibly also underwent purification by levigation prior to use. Capable of analysing over 40 elements with a typical long term precision of <2%, this high precision ICP-MS method proves to be very powerful for grouping and characterising archaeological ceramics. Combined with geochemical interpretation, it can provide insights into the raw materials and techniques used by ancient potters.     

Pb and Sr Isotopes and the Provenance of the Painting Materials of Cornelius Krieghoff in 19th‐Century Canada

Radiogenic lead and strontium isotope data are presented for lead‐ and calcium carbonate/barium sulphate‐containing paint and ground samples from 15 paintings, executed between 1844 and 1871, by 19th‐century Canadian artist Cornelius Krieghoff. Like many artists of this era, Krieghoff used lead‐based pigments such as lead white, chrome yellow and Naples yellow, and extenders such as calcium carbonate and barium sulphate. The lead isotope analyses of the majority of these pigments are consistent with the isotopic compositions of lead mined from European lead deposits in England and/or Germany. However, three samples from Krieghoff's early career yield lead isotope compositions that are much more radiogenic than European sources. The lead isotope compositions of these three samples are consistent with the addition of a more radiogenic lead component that is similar to the lead derived from North American lead deposits in Missouri and Illinois (Mississippi Valley Pb–Zn type deposits). The strontium isotope compositions of the extenders suggest that the raw materials for calcium carbonate or barium sulphate extenders were largely derived from Palaeozoic to modern‐day marine environments. This study shows that pigments manufactured from North American lead were being incorporated into Canadian paintings as early as 1844.