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Abstract  

The use of thermogravimetric analysis–mass spectrometry (TGMS) to study the state of preservation of archaeological bones has been investigated. As part of a collaborative multi-analytical study, bones exhumed from graves of the late Roman period in France and Italy were examined. A decrease in organic matter for the archaeological bones compared to that for new bone was confirmed, demonstrating that diagenesis of aged bones can be detected using TGMS. Different amounts of collagen were determined for bones from different graves and could, for the majority of specimens, be correlated with the visually observed preservation states.

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Abstract  

Interest in mass spectrometry with an inductively coupled plasma as an ion source and its association with laser ablation as a sample introduction technique (LA-ICP-MS) has steadily increased during the past few years. After a description of the analytical procedure and the calculation method, we show the potential of this technique to characterize non destructively archaeological artefacts. A comparison is made between the results obtained with LA-ICP-MS and those obtained on the same objects with other analytical methods. A large variety of archaeological materials such as obsidians, glasses, glazes and flints are studied.

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Abstract  

Two fundamentally different standardization systems, widely used in the neutron activation analysis of archaeological ceramics and of other materials, have been intercompared using procedures of high precision. The results should permit data standardized under either system to be transformed to the opposite system. The two systems are generally known as the Asaro-Perlman standard and the BNL Six-Rocks standard.

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Summary  

Multielement analysis of archaeological artifacts for the purpose of correlating chemical composition in an effort to determine provenience has become a well-known and accepted procedure. In this study, inductively coupled plasma-mass spectrometry with laser ablation probe (LA-ICP-MS) for the direct study of solids was used to generate elemental data for comparison with existing instrumental neutron activation analysis (INAA) data. Matrix element Al was used as an internal standard in the ICP work to normalize for variations in sample density and sample mass ablated. While absolute accuracy and precision for the ICP data are inferior to INAA, multivariate statistical analysis of data resulting from the two methods demonstrates a high degree of comparability. Sample cluster assignments differed in only 4.7% (4 out of 86) of the cases. Results show a clear usefulness for LA-ICP-MS in archaeological compositional analysis.

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Abstract  

Archaeomagnetic studies in Bulgaria have a long history and the well established secular variation curves of the three elements of the ancient geomagnetic field (declination, inclination and intensity) for the last 8000 years enable the dating of archaeological features of burnt clay, independently of other methods. The determination of ancient palaeointensity is the most difficult characteristic and requires very cautious evaluation of the suitability of the burnt clay material. The present paper is an overview of the methodological progress in studying the suitability of the materials for archaeomagnetic investigations. The main rock-magnetic methods and summary of the most common results are presented involving the archaeomagnetic practice in the palaeomagnetic laboratory in Sofia. In addition, supplementary information obtained by magnetic measurements, which can be helpful for archaeology, are discussed. An example of archaeomagnetic dating procedure is also presented.

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Abstract

The paper presents an application of carbon isotope analysis in the archaeometric research of graphite-tempered ceramics. Graphite separated from Celtic graphitic ceramics were analysed from Szűr, Szajk and Dunaszentgyörgy archaeological sites from the South Transdanubian region of Hungary. Variation in δ13C values of graphite in the sampling sites is attributed to the characteristics of graphitic metamorphic rock used for tempering. The carbon isotope results will serve as basis for further provenance research on graphite.

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Abstract  

The structure and the preservation state of artistic heritage and archaeological findings have been studied by the analysis of the heat diffusion process in the sample. The investigations have been performed by non-invasive time resolved infrared thermography(IRT). Thickness maps, buried defects detection, inhomogeneity and corrosion analysis, as well as the quality check of welding and reinforcements elements, have been performed on the studied samples.

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Abstract  

Data on the concentrations of K, Ca, Ti, Fe, Cu, Zn, Ga, Rb, Sr and Zr obtained by PIXE and of B, F, Na, Mg, Al, Si and Cu obtained by proton-induced prompt gamma-ray spectrometry were used to characterize archaeological artefacts and source materials by multivariate analysis. The mathematical approaches employed were cluster analysis using nearest-neighbour data, multidimensional scaling and correspondence analysis.

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Abstract  

Simulation of waterlogged archaeological woods was carried out by immersion of fir and chestnut wood samples into sea water at different temperatures (room temperature and 40°C). The effects of metals in contact with woods were simulated by inserting in some specimens of the two types of wood copper or iron nails, the most important metals from the archaeological point of view. The effects of this ageing simulation on woods were studied by different characterization methods. At first we have performed gravimetric analyses, controlling the mass increase of immersed wood in function of the time of immersion and the temperature of the bath. Then, thermogravimetry, differential thermal analysis, differential scanning calorimetry in oxygen flux were used. The alteration of wood was observed by means of the peak temperatures of DTA, DTG and DSC variation and by the mass losses observed during heating, evaluated on the basis of the measured thermal data. The samples were woods powder obtained by milling. Complementary characterization of the woods was performed by evaluating the crystallinity of cellulose by means of X-ray powder diffraction. The change in colour of woods during ageing was checked by means of spectrophotometric measurements in the visible region. X-ray fluorescence was used to investigate the penetration of metals into wood samples. An artificial ageing treatment with NaOH and O3 was also performed. Finally, a comparison between the effects of artificial alteration realised in our specimens and natural degradation observed in archaeological woods, was performed.

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Abstract  

Neutron activation analysis (NAA) is a very sensitive and accurate multielement analytical method that is widely applied to the investigation of environmental and archaeological problems. The first part of this paper is a review of pollution studies of toxic trace elements in sediments, seawater and marine organisms of Saronikos Gulf, Greece by NAA. The second part of this paper is a review of provenance studies based on minor and trace element research in ancient ceramics, obsidian, flint, limestone, marble and lead by Instrumental NAA, performed at the NCSR Demokritos.

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