The investigation of ancient pottery

Summary Ancient ceramic samples (single fragments and different parts of pots, unbroken and repaired; total about 180 samples) dated from the transitional period of late Bronze to early Iron Age (VIII-VI centuries BC) and early Iron Age (VII-IV centuries BC) were investigated by thermal analysis, X-ray powder diffraction, petrography, and scanning electron microscopy equipped with the energy-dispersive X-ray analyzer. In addition to that, to identify the clay sources for the ceramic manufacturing, about 15 samples of clays and soils found near archeological digs and taken from the mineralogical museum were investigated. We found out that the calcite content of ceramics is a very informative parameter for the identification of the clay source for the pottery manufactured at low technological level (low-temperature firing).     

Non-Destructive In-Situ Study of White and Black Coating on Painted Pottery Sherds From Bancun Site (Henan,China) by Raman Microscopy

Abstract

Pottery sherds from the archaeological site of Bancun (Henan, China) were analyzed by Raman microscopy and the pigments used in the coating of this ancient (c. 4000–5000 BC) pottery were determined. It was found that bauxite was used to make the white pigment. The black coating was identified as a magnetite and its particle size was in the nanometer range. This work also showed that the size of pigment had influence on the color of the coating. In principle, Raman spectra could be used not only to identify the mineral source of the pigment but also to estimate the particle size of the pigments.     

An integrated spectroscopic approach to investigate pigments and engobes on pre‐Roman pottery

Painted Canosa ceramics were examined to identify the nature of the pigments employed and their manufacturing technology. A multi‐technique approach was used, comprising Raman microspectroscopy and laser ablation hyphenated to inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS). The analysed samples were mainly produced for burial in tombs and were not intended for everyday use. They belong to the period between the end of the mid‐7th century and the first half of the 4th century BC, and were excavated from the Toppicelli archaeological district near the suburbs of Canosa (Puglia, Italy). Forty‐eight pottery fragments were available for this study. No handling of the samples was required for the Raman study, and it was possible to excise the pigmented layer in such a way that the lacunae were not distinguishable to the naked eye due to the micrometric size of the laser spot as far as LA‐ICP‐MS is concerned. Their combination turned out to be quite useful for the investigation of these archaeological materials: the chemical nature of the white, red, brown and black pigments employed in the pottery manufacture was investigated. Iron and manganese compounds were identified as the red and brown/black main colouring substances, respectively; on the other hand, whites and engobes (whitish slips) were based on kaolinite. This set of colouring substances is of importance, as it enabled the artisan to obtain in one oxidising firing cycle brown, black and red paints. Finally, the finding of manganese black in these Canosa potsherds confirms that Canosa was an important centre connecting the near East to central Italy and Europe since the pre‐Roman age. Copyright © 2010 John Wiley & Sons, Ltd.     

Raman and infrared analysis of glues used for pottery conservation treatments

The conservation of ceramics and glass involves the repair or the restoration of broken and fragmented artefacts with polymer adhesives and gap fillers. In the past, many different adhesives had been used. Re‐restoration is often required and the fast identification of adhesive residues on objects would be very useful to define the best of way to remove them, in particular to avoid the use of noxious chemicals. Sixteen pottery artefacts restored during the 19th and 20th centuries at the Musée National de Céramique in Sèvres have been analysed by non‐destructive Raman microspectroscopy. For comparison purposes, the artefacts were also sampled in order to acquire infrared (IR) absorption spectra in KBr pellets. Modern adhesives (methyl metacrylate/acrylate, vinyl acetate, polychloroprene, methyl 2‐cyanoacrylate and diglycidylether biphenol) were also characterised with the same methods. IR and Raman spectra were obtained for all ancient glue residues, but among the 16 analysed items, only 7 adhesives have been identified unambiguously, and an assignment proposed for 4 others solely on the basis of the Raman signature. Copyright © 2009 John Wiley & Sons, Ltd.     

Raman Microspectroscopic study of Iberian pottery from the La Vispesa archaeological site,Spain

Raman microspectroscopy has been employed for the characterization of 16 samples of ancient Iberian pottery. These sherds of vessels were found in the archaeological site of La Vispesa in Tamarite de Litera (Huesca, Spain) and correspond to the Iberian time. The composition of certain mineral phases such as non‐plastic inclusions has been particularly considered with a view to obtaining information on the source materials and their provenance, as well as the technological conditions of ceramic production. Typical minerals such as calcite and quartz were found in most of the samples. The presence of anatase in a group of the samples suggested the use of different clays in the production of the vessels. Furthermore, the absence of rutile in these samples, together with the identification of calcite, is indicative of a mild firing temperature. Hematite was identified in all samples, both in the ceramic body and in the decoration. Differences in the position of the bands and relative intensities characterized hematite in terms of crystallinity and origin. An attempt to assign the samples to different production centers was made according to their chemical composition and morphology. Copyright © 2011 John Wiley & Sons, Ltd.     

北魏墓彩绘陶俑颜料的显微拉曼光谱分析

利用拉曼光谱对洛阳地区两座北魏墓出土陶俑的彩绘颜料进行了分析, 与标准颜料样品的拉曼光谱相比较, 识别出了陶俑所使用的红色、黑色、白色和蓝色颜料的显色成分。研究结果表明, 显微拉曼光谱分析技术非常适合对古墓葬彩绘陶俑进行成分分析。     

Chemical characterisation of ancient pottery from south of Italy by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) Statistical multivariate analysis of data

Chemical characterisation has been carried out on 58 fragments of archaeological pottery from pre-classical sites in Apulia and Lucania, regions in southern Italy. Fourteen elements were determined by atomic emission spectroscopy by using inductively coupled plasma source. Statistical techniques, such as principal component analysis and clustering analysis, have been utilised to define grouping of different pottery items. Tests performed showed that the analysed shards were differentiable mainly by age and provenance.     

回归分析在殷墟墓葬分期中的应用

数理统计方法，在我国考古学中的应用，目前处于探索、研究阶段。本文试用回归方法，建立殷墟墓葬分期的多元线性回归模型，并确定出墓葬分期的预测区间。     

The influence of optical properties of shallow shelf seas on temperature structure and acoustic propagation

The penetration of solar radiation below the sea surface is not always taken into account in numerical ocean models, even though its influence on the temperature (and therefore sound speed), structure of the water column can be significant, especially in shallow shelf seas where water turbidity tends to be high. Variations in sound speed structure have a consequent effect on the propagation of sound underwater which, in turn, influences the performance of sonar systems. A double exponential parameterization for the penetration of solar radiation with depth was implemented in an N × 1D turbulence closure model of the UK shelf seas. The model was run along a section through the Celtic Sea Front, with sets of optical extinction coefficients representing different water clarities, for one month to simulate the generation of the front, and the results were compared with a control model run in which all solar radiation was absorbed in the surface layer. Temperature structure and sound propagation were only affected by changes to the optical parameterization on the stratified side of the front, where consequent variations in acoustic propagation loss of up to 10 dB relative to the control were simulated using an acoustic model. Changes in propagation loss were greatest for acoustic sources placed in the stratified water above the thermocline. Similar changes to the optical parameterization made on the well-mixed side of the front had no discernible effect.     

Estimate of firing temperatures through bone-based chalcolithic decorated pottery

Guadiana River Chalcolithic middle basin (Badajoz, Spain) pottery was in many cases decorated with bone, which suffers a hydroxyapatite to β tri-calcium phosphate transformation while firing. The evolution of physico-chemical characteristics of bone decorations and experimentally heated fossil bone as a function of temperature through 1) major XRD planes, and 2) OH librational mode at 630 cm^–1 in the FTIR spectra let us establish a correlation between the physico-chemical features and firing temperature, allowing the estimate of firing temperatures for bone decorated pottery. What is a reliable criterion to differentiate over potters behavior and skill during the pottery production.