A SPECTROSCOPIC INVESTIGATION OF PIGMENT AND CERAMIC SAMPLES FROM COPÁN,HONDURAS*

A combination of micro‐Raman spectroscopy, micro‐infrared spectroscopy and SEM–EDX was employed to characterize decorative pigments on Classic Maya ceramics from Copán, Honduras. Variation in red paint mixtures was correlated with changing ceramic types and improvements in process and firing techniques. We have confirmed the use of specular hematite on Coner ceramics by the difference in intensities of Raman bands. Different compositions of brown paint were correlated with imported and local wares. The carbon‐iron composition of the ceramic type, Surlo Brown, was confirmed. By combining micro‐Raman analysis with micro‐ATR infrared and SEM–EDX, we have achieved a more comprehensive characterization of the paint mixtures. These spectroscopic techniques can be used non‐destructively on raw samples as a rapid confirmation of ceramic type.     

Analysis of adhering organic residues of two “coupes-à-socles” from the Neolithic funerary site “La Hougue Bie” in Jersey: evidences of birch bark tar utilisation

The “coupes-à-socle” (footed cups) are ceramics which can be found in domestic Neolithic contexts in Brittany (Castellic, Auzay-Sandun), but more generally in non-domestic areas. Their ceremonial function has often been evoked, in particular as a perfume burner. The analysis by GC and GC/MS of two samples from the “Hougue Bie” (Jersey) passage graves showed the presence of vegetable fatty acids, degraded n-alkanes and terpenoïds, biomarkers of birch bark tar. The presence of such substances could be explained either by the use of the “coupes-à-socle” for burning birch bark tar as an odoriferous product or their use as an everyday vessel for heating and increasing tar plasticity. However, the limited occurrence of this type of ceramic in habitat sites supports the former utilisation. This first report of the presence of birch bark tar in “coupes-à-socle” thus suggests use of this tar as an odoriferous product, in addition to its numerous, previously recognised, more technical uses.     

RELATIONSHIP BETWEEN THE COLORATION AND THE FIRING TECHNOLOGY USED TO PRODUCE SUSA GLAZED CERAMICS OF THE END OF THE NEOLITHIC PERIOD*

Ancient decorated potteries from Susa (Mesopotamia) dating from 4200 to 3700 bc , were studied in order to determine the origin and the nature of the raw materials used, and to identify the technological processes applied to make the ceramic bodies and their decorations. Bulk compositions were determined by particle induced X‐ray emission (PIXE), while the microstructure and the mineralogical phases were studied using scanning electron microscopy (SEM), energy dispersive X‐ray analyses (EDX) and X‐ray powder diffraction (XRD). The results showed that the raw materials used to elaborate these potteries were similar for all the ceramic bodies (carbonates and iron and magnesium‐rich clays containing sand), and for all the decorations (iron oxides, silica, potassic and alumina sources). The variations of coloration of the ceramics and of their decorations were due to different firing temperatures. The ranges of firing temperatures used by potters were evaluated on the basis of mineral stability domains.     

The palaeo-Christian glass mosaic of St. Prosdocimus (Padova,Italy): archaeometric characterisation of tesserae with antimony- or phosphorus-based opacifiers

The present paper reports the results of archaeometric characterisation of the opaque tesserae, intentionally coloured with antimony- or phosphorus-based opacifiers, coming from one of the two only palaeo-Christian glass mosaics known in the Veneto region (Italy), i.e., the mosaic which decorated the votive chapel of St. Prosdocimus in Padova. In particular, 55 tesserae belonging to glass types “White”, “Blue”, “Yellow”, “Green” and “Brown” are examined here. The multi-methodological approach (SEM-EDS, EMPA, XRPD, imaging spectroscopy coupled, in some cases, with XAS) gave valuable insights into the complexities of palaeo-Christian glass mosaic production technologies. Two main groups are identified, one characterised by glassy matrixes and opacifiers (calcium or lead antimonate) typical of the Roman period and comprising all “White”, “Blue”, and “Yellow” tesserae and some “Green” ones, and the other characterised by glassy matrixes and an opacifier (calcium phosphate) typical of the 6th century AD, composed of “Green” and “Brown” tesserae. This suggests that, during that century there was a gradual change from older to “new” production technologies: although new opacifiers such as calcium phosphate started to be used, the frequent use of antimony-based ones (43/55 samples) supports the hypothesis that their systematic use was extended until the 6th century, although re-using old tesserae cannot be completely excluded. In addition, comparisons with compositional groups already identified in the “gold” tesserae of the same mosaic and tesserae from Ravenna demonstrate that both the same “base compositions” of the glass were used to produce transparent and opaque glass. This evidence, coupled with the results of the historical-artistic study, suggests technological connections between Padova and Ravenna, the capital of Byzantine mosaics in Italy. Micro-structural observations and chemical analyses of the Paduan antimony-based opacified glass demonstrate that different processes and raw materials were used in their production. Both in situ and ex situ crystallisation can be identified for calcium and lead antimonate in Paduan tesserae, whereas the production of tesserae opacified with calcium phosphate generally appears to be highly standardised. Although the opacifiers used in the Paduan tesserae support technological transitions, the colouring elements identified here, i.e., iron and manganese for white, yellow, brown and some green tesserae, cobalt for blue, and copper for blue and green, suggest continuity, because their use is widely testified in the production of both transparent and opaque glass artefacts dating from the Bronze Age until Medieval times, from whichever archaeological site the samples come. Peculiar relationships among the oxidation states of colouring elements, their contents in the glassy matrix, the types of opacifiers used, and the final colour of tesserae were identified. In addition, the correlations of cobalt and/or copper with other elements, together with identification of relics of colouring and “metallic” droplets, allow us to speculate on possible sources and production technologies. Lastly, identification of newly formed crystalline inclusions in tesserae also yields information on kiln temperatures, which ranged between 900 and 1150 °C, a range easily reached in the furnaces of the 6th century AD.     

Technological features of Apulian red figured pottery

Apulian red figured pottery samples, dating back to the 5th and 4th centuries BC, from the archaeological site of Monte Sannace (Gioia del Colle, Bari, Italy) have been characterized from the physical–chemical, mineralogical and morphological points of view. Scanning electron microscopy, X-ray diffraction and atomic spectroscopy investigations have been carried out on the ceramic body, red decorated area and black gloss of the fragments, with the aim of outlining the technological features and of defining the nature of coatings and decorations. All 5th century fragments show the same features: fine texture of the ceramic body, red figures saved from the ceramic paste and black gloss painted directly on the ceramic body. The statistical treatment of compositional data of ceramic bodies excludes the local production of these objects. As regards the 4th century fragments, some show similar features to the 5th century ones; however others are characterized by the coarse texture of their ceramic body and an intermediate red layer of finer clay between the black gloss and the ceramic body. The analytical results make it possible to distinguish two different production technologies of red figured Apulian vases in Monte Sannace during the 4th century BC. Certain vases were produced using the “classic” Attic technology and others with a different technique, not previously known, which involved the application of a red engobe layer on the clay paste, before the black gloss painting.     

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.     

Technological examination of Neolithic-Bronze Age pottery from central and southeast Europe and from the Near East

Scanning electron microscopy is used to examine sequences of pottery sherds from central and southeast Europe, Greece and the Near East spanning the period from the Neolithic to the Bronze Age, in order to obtain information on the ceramic technologies employed in antiquity. On the basis of the vitrification observed and the chemical composition, the types of clay and firing procedures (temperature and atmosphere) employed in the manufacture of the pottery are defined. Two under-lying trends in the associated ceramic technologies are thus identified. The first is based on the use of non-calcareous or “unstable” calcareous clays fired in a reducing atmosphere at temperatures below 800 °C and the second on the use of “stable” calcareous clays fired in an oxidizing atmosphere at temperatures in excess of 800 °C.     

Working Without a Net: Recent Trends in Ceramic Ethnoarchaeology

This paper reviews ceramic ethnoarchaeological research conducted subsequent to Kramer's (1985) seminal stock-taking. Among current trends are a continued interest in the relationship between ceramics and economic specialization, the degree to which manufacture constitutes a technological style, and the link between pots and formation processes as represented in assemblage sizes, use-lives, and recycling. At the same time, some pesky theoretical issues continue to be sidestepped in the current literature. Despite its reputation as a pleasant break from the real business of archaeology, this paper argues that ceramic ethnoarchaeology can and should play a more substantial role in archaeological investigations.     

Who are the yakut khorolors? (a contribution to the issue of ethnic identification)

The origins of the Khoro ethnic group which represents a major component in the ethnic structure of the Yakut people is an ongoing issue in the context of Yakut ethnography. Buryat scholars believe that prior to the 13th century, the ancestors of the Khorolors (pl. of “the Khoro”) lived on the western side of Lake Baikal. Here they are said to have formed a single community with the Khori people whose descendants now make up part of the Buryat people and inhabit the Trans-Baikal region. The basis for the identifi cation of both groups was limited only to the similarity between the selfidentifying names “Khoro” and “Khori,” which is hardly suffi cient. In the meantime, the analysis of specifi c folklore and ethnographic materials, in particular, the themes of “Raven” and “Eagle” leave no doubt of the Paleo-Asiatic origins of the Yakut Khorolors.     

Compositional Analysis of Ceramics from Goguryeo Fortified Sites in Central Korea

The aim of this paper is to investigate whether the ceramics from the Goguryeo fortified sites of the Han River region in central Korea were manufactured and consumed locally during the southern expansion of the Goguryeo State (475–551 ce ). For this research, 88 ceramic samples from seven contemporary sites in the southern territories of Goguryeo were sampled and analysed by ceramic thin‐section petrography and neutron activation analysis (NAA). In addition, to establish a possible chemical fingerprint at Hongryeonbong Fort 2, five clay specimens were also gathered and analysed from the pottery firing structure. The results of this analytical study indicate that the majority of the ceramics from the Goguryeo fortified sites of central Korea were produced and circulated within this newly acquired region. In addition, it is highly probable that Hongryeonbong Fort, which contains the remains of what may be ceramic firing architecture, is the place of production for the ceramics.     

GLAZED CERAMIC MANUFACTURING IN SOUTHERN TUSCANY (ITALY): EVIDENCE OF TECHNOLOGICAL CONTINUITY THROUGHOUT THE MEDIEVAL PERIOD (10TH–14TH CENTURIES)*

Archaeometric investigation allowed the characterization of two important classes of ceramics: ‘vetrina sparsa’ and ‘invetriata grezza’. Their archaeological peculiarity makes them particularly suited for tracing the evolution of glaze manufacturing in southern Tuscany throughout the medieval period (10th–14th centuries). These ceramics were found in different sites of historical importance, and also from a mining perspective. Local copper, lead, zinc and iron mineralizations supported the growth of several settlements in the vicinity of the mines. The many castles and different archaeological finds (ceramics, glazed ceramic, slag etc.) attest to the intense mineral exploitation of the area from at least the first millennium bc up to the modern period. In light of these geological and archaeological characteristics, archaeometric investigation was intended to provide insight into ancient technical knowledge of ceramic glazing and to determine the source area for raw materials in the medieval period (10th–14th centuries). Ceramic bodies were analysed through OM, XRDp, SEM–EDS and XRF, while coatings were investigated through SEM–EDS. Mineralogical, petrographic and chemical analyses revealed slightly different preparation and firing processes for the two classes of ceramics. These data suggest the continuity through the centuries of the ‘vetrina sparsa’ and ‘invetriata grezza’ production technology. The mineralogical phases, such as monazite, xenotime, zircon, barite, Ti oxide, ilmenite, titanite, tourmaline and ilvaite, and the lithic (intrusive and volcanic) fragments detected within the ceramic bodies suggest a source area in the vicinity of the Campiglia mining district. Lastly, the presence of Cu–Zn–Pb (Ag) and Fe sulphide mineralizations (materials used to produce glaze) in the area supports the hypothesis of local manufacture.     

TECHNOLOGY AND COLOUR DEVELOPMENT OF HISPANO-MORESQUE LEAD-GLAZED POTTERY

Lead-glazed pottery from the medieval workshop of Les Olleries Majors (Paterna, Spain) has been studied by Mössbauer spectroscopy, X-ray diffraction, X-ray fluorescence and optical spectroscopy. Yellow, brown and honey-coloured glazes occur on pots glazed on only one surface. They have virtually identical compositions and transmittance spectra, their apparent differences in colour are due to the colours of the underlying pastes. Yellow glazes occur on cream-coloured calcareous bodies, honey-coloured glazes occur on less calcareous bodies with some development of hematite, while brown glazes occur on red siliceous cooking-pots. Green glazes are found on pots glazed on both surfaces; the glazes trapped CO₂ evolved by decomposing carbonates, resulting in an internal reducing environment. This caused the reduction of iron to the ferrous state which coloured the glaze green by diffusion.     

Low-Fired Earthenwares in the African Diaspora: Problems and Prospects

Local earthenware associated with enslaved African populations in the Americas, variously called Colono-Ware, Afro-Caribbean Ware. Yabbas, and Criollo ware, has received considerable attention from researchers. What unifies this disparate group of ceramics is not method of manufacture, design and decoration, or even form and function but the association or potential association with African diaspora populations. The ceramics incorporate some skills and techniques possibly brought by African potters to the Americas, as well as skills reflecting European and Native American traditions, and local adaptations in form, function, and manufacture. Analogies linking African ceramic traditions to American industries have at times been employed uncritically and have relied on generalized characteristics to infer overly specific meanings. With particular reference to low-fired earthenwares from Jamaica, this paper examines the historical and cultural context of these ceramics and the methodological and theoretical problems faced in their interpretation.     

陕西咸阳出土东汉陶器表面彩绘成分研究

为掌握陕西省咸阳市渭城区周陵镇费家村南两座东汉墓葬M17和M19出土15件陶器表面彩绘成分及保存现状,通过XRF,XRD,FTIR和SEM-EDS等分析仪器进行检测。经分析检测发现:M17出土6件陶器表面使用铅丹作为颜料,部分铅丹已转化为白色碳酸铅(PbCO_3)。M19出土陶器表面分别使用朱砂和铁红颜料,同时确定在部分器物表面使用了髹漆工艺。在M19出土的3件器物口沿处发现二氧化锡层,通过扫描电镜能谱分析和文献研究,确定其应为单质锡氧化而来,且使用锡汞齐方法镀锡,为进一步认识和理解这批器物提供了基础。     

SIENESE ‘ARCHAIC’ MAJOLICA: A TECHNOLOGICAL STUDY OF CERAMIC BODIES AND COATINGS*

The aim of the present study is to reconstruct the production technology of Sienese ‘archaic’ majolica in the early decades of the 14th century ad . The integration of archaeological data with archived data revealed the presence of numerous workshops, suggesting that the Sienese tradition of majolica production was well developed up until the end of the 16th century. Sixty‐seven uncoated and coated waste products were analysed. The ceramic bodies were examined by OM, XRDp, SEM–EDS, XRF, ICP–OES, ICP–MS and INAA. The coatings (enamels and glazes) were analysed by SEM–EDS and Raman microspectroscopy. The results showed that ceramics were rejected due to poor control of the firing temperature (technological wastes), faulty production technology (wastes of uncertain classification) and accidents (post‐firing wastes). Finally, the analyses revealed extreme homogeneity of the ceramic bodies, indicating the continued use of the same raw material over the whole period studied.     

Fire and ritual: bark hearths in South-American Tupiguarani mortuary rites

High proportions of bark pieces (up to 85% of the charcoal content) were found in several hearths from Morro Grande archaeological site (Southeastern Brazil). This site, dated between 3220–2840 and 1820–1390 yrs cal BP, is associated to the Tupiguarani Tradition, attributed to supposed ancestors of Tupinambá native populations, who occupied the major part of the Brazilian coast in the XVIth century. Bark hearths, archaeologically associated with the mortuary ritual, were found encircling a funerary urn and associated with ceramic fragments painted with elaborated patterns in black, white, and red. Other hearths, spatially isolated from the funerary area, were associated to fragments of utilitarian non-painted ceramics and therefore attributed to domestic contexts. These ones presented few or no bark fragments. It is clear that bark was intentionally selected as fuel for the funerary hearths. Although bark is related, in historic accounts, as a specialized firewood for ceramics firing, its presence in ritual context has not been previously recorded. In this paper, the anthracological record is discussed in the light of ethnographic and historic accounts. A possible explanation for the presence of bark hearths in funerary context is proposed, suggesting it might be a symbolic parallel with the quotidian: the potency and power of transformation of bark as a fuel would be regarded in a spiritual level, achieving the transformation of the body soul in the revered soul – an Ancestor.     

Material evidence for the use of Attic white-ground lekythoi ceramics in cremation burials

White-ground lekythoi ceramics offer important evidence for funeral practices in Ancient Greece (5th century BC). The images painted-on these oil containers provide the best visual narrative for the events surrounding death, including indications that the vessels themselves were used as part of the funerary rites. However, until now, their specific function and treatment within the funeral ceremony was not well understood. We present here material evidence that the vessels were ritually burned, together with the body of the deceased, during cremation, as evidenced by a diffuse purplish-red discolouration found on many white-ground lekythoi. Through EPMA and μXAS studies, we show that: (1) this characteristic purplish-red discolouration is due to the presence of metallic copper nano-particles embedded in a glassy layer; (2) this metal-glass matrix formed as the result of a high temperature reaction between painted-on Cu-based pigments (e.g., Egyptian blue) and the white-ground ceramic slip; and (3) the reaction occurred under a reducing environment. Given the mortuary context for these vessels, we propose the reduction firing to which the vessels were exposed was that associated with the cremation of the body. The observation of discontinuous formation of the purplish-red discolouration along adjoining fragments supports the hypothesis that the vessels were broken prior to being burned. The majority of lekythoi in museum collections lack information on their original archaeological context, and our data suggest the presence of this purplish-red discolouration may serve as a visual marker for cremation. As such, it is expected our findings will provide a new basis for interpreting how this important class of ceramic, and associated iconographic imagery, relates to Athenian funerary practices and the ancient Greek notion of death.     

MÖSSBAUER SPECTRA OF IRON IN CERAMICS AND THEIR RELATION TO POTTERY COLOURS

The chemical states of iron in a few selected clays and ceramics have been ascertained employing the technique of Mössbauer absorption. The effects upon the iron in firing the clays under different conditions have also been measured. Colour changes are correlated with the various chemical states of iron before and aftefiring.     

Magnetization of Ancient Ceramics

The saturation magnetization σ of soft baked pottery appears to be determined during the firing process by transitions between the iron oxides magnetite, maghemite, hematite and perhaps goethite. The finding of large variations in σ motivated the design and construction of a ‘magnetization–gravitation’, or ‘MG’, balance for rapid non‐destructive magnetization measurements. The first results with this MG balance are presented: iso‐σ contours, typical histograms and correlations with colour features. Practical MG applications are summarized.     

A truly refractory crucible from fourth millennium Tepe Hissar, Northeast Iran

From the Early Chalcolithic to the Late Iron Age, melting and smelting crucibles were usually made from non-refractory ceramic fabrics, which required heating of the charge from within the crucible to avoid collapsing the ceramic itself. In this paper, an unusual melting crucible from Northeast Iran, radiocarbon-dated to the Late Chalcolithic (ca. 3600 BCE), will be presented that significantly changes our understanding of the development of technical ceramics in Southwest Asia. This crucible, made of a highly refractory talc-based ceramic held together by an outer layer of traditional non-refractory ceramic, is to our knowledge unprecedented at such an early date. As will be argued, this ancient crucible was heated from the exterior or from below and not from the interior. This method of firing, combined with the highly-specialized construction technique, makes this crucible so far unique in prehistoric metallurgy, and forces us to re-examine traditional models for the development of technical ceramics and metallurgical practices in the Old World.