X-RAY FLUORESCENCE ANALYSIS WITH SYNCHROTRON RADIATION ON THE INKS AND PAPERS OF INCUNABULA

Non-destructive X-ray fluorescence analyses induced by white synchrotron radiation (SYXRF) have been performed on a page of the Gutenberg Bible and 21 other different single leaves printed in the years 1470 to 1500. Absolute elemental areal densities for the papers and the inks are reported. The known high Cu and Pb content in Gutenberg's ink is confirmed. The elemental compositions of the other inks, if measurable by XRF at all, are in general very low, governed only by a few additional elements and found to be not distinctive for a known printer. This will render an identification of the printer or printing offices by ink composition analysis in the period after 1470 difficult.     

Black Gloss Pottery: Production Sites and Technology in Northern Etruria,Part II: Gloss Technology

The present study aims to understand the reasons for the visual differences of black gloss pottery found in northern Etruria. The results obtained by conventional (scanning electron microscope, electron microprobe) and synchrotron (X‐ray diffraction, X‐ray absorption spectroscopy) techniques indicate that the thickness, porosity or chemical composition of the different types of gloss cannot be used as the principal distinguishing factor. The size of quartz or feldspar crystals may well be a critical factor responsible for the matt effect in some samples, while the range of mixtures of iron compounds indicated by XRD and XAS could be the reason for differences in colour and reflectivity. The Fe L‐edge XAS results in particular show that a correlation does exist between the oxidation state characteristics and the visual appearance. The Si, Fe and Al contents seem to further discriminate the different types of gloss that have differing visual appearances.     

DETERMINATION OF PIGMENTS AND BINDERS IN POMPEIAN WALL PAINTINGS USING SYNCHROTRON RADIATION – HIGH‐RESOLUTION X‐RAY POWDER DIFFRACTION AND CONVENTIONAL SPECTROSCOPY – CHROMATOGRAPHY

The employment of synchrotron techniques complemented by conventional laboratory systems has allowed us to deepen and improve our knowledge of Roman wall painting procedures. The palette identified in wall paintings from Pompeii and Herculaneum from the second century bc includes goethite, hematite, cinnabar, glauconite, Egyptian blue, and other components such as calcite and aragonite. Proof of the use of organic binders is provided by FTIR and PY–GC/MS. Therefore, the possibility of the use of ‘a secco’ techniques cannot be ruled out. Pigments in wall paintings are usually found in small percentages and conventional X‐ray diffractometers do not detect them. Synchrotron radiation – high‐resolution X‐ray powder diffraction has allowed identification with only a few micrograms of sample.     

SYNCHROTRON FTIR MICRO‐SPECTROSCOPY APPLIED TO THE STUDY OF POLISHED SERPENTINITE ARTEFACTS: A NON‐DESTRUCTIVE ANALYTICAL APPROACH

In prehistory, serpentinite was one of the most frequently used raw materials to produce polished stone artefacts. Several conventional analytical techniques can be applied to identify the serpentine minerals, but their application generally requires a powdered sample. This implies that the artefacts to be analysed must be damaged, and the possibility of analysing a mixture of different serpentine polytypes is high. The use of spatially resolved techniques is therefore a necessity to overcome this problem. Several thin sections of serpentinitic rocks and prehistoric axes have been analysed by synchrotron radiation Fourier transform infrared micro‐spectroscopy. The spectra were acquired directly on specific points of polished stone artefacts and this allowed the recognition of the different polytypes of serpentine minerals without causing any damage to the objects. The results show the infrared micro‐spectroscopy technique to be a useful tool for the characterization of archaeological lithic material.     

CLIMATE FORCINGS AND THEIR INFLUENCE ON ALPINE HISTORY AS RECONSTRUCTED THROUGH THE APPLICATION OF SYNCHROTRON‐BASED X‐RAY MICROFLUORESCENCE ON LAYERED STALAGMITES*

Solar variability and volcanic activity strongly interact with climate and the environment. Synchrotron radiation X‐ray microfluorescence (micro‐XRF) to an annually laminated Alpine stalagmite confirmed that annual laminae result from hydrological variability and changes in the duration of soil microbial degradation. The latter is modulated by solar variability. At the centennial timescale, growth rate and solar activity appear to be correlated with temperature change, with low temperatures at solar minima. By combining micro‐XRF and absorption spectroscopy techniques (XANES), we also found that speleothems are a new archive of aerosol sulphate related to volcanic activity. Peaks in S‐concentration from c. 5.2 to 5.0 ka bp in an Alpine stalagmite suggest that multiple volcanic sulphate aerosol emissions enhanced Mid‐Holocene summer cooling, thus favouring the preservation of the Alpine Iceman mummy in a persistent ice casket.     

A Study Of The Firing Technique Of Pottery From Kaman‐Kalehöyük,Turkey, by Synchrotron Radiation‐Induced Fluorescence X‐Ray Absorption Near‐Edge Structure (Xanes) Analysis*

Fe K‐XANES spectra of a series of pottery sherds excavated from the archaeological site of Kaman‐Kalehöyük, Turkey, were measured to reveal the firing technique of the pottery. The analysis disclosed relationships among the chemical form of the iron, the firing conditions and the colour of the pottery. The pottery referred to as ‘Grey Ware’ found at this site was classified into two groups according to the chemical form of the iron. Also, it was revealed that the Iron Age pottery referred to as ‘Cream Ware’ was produced first under reducing conditions, and then fired under oxidizing conditions.