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Cobalt was commonly used as a colourant in the Egyptian glass industries of the 18th dynasty, dark blue glass being a regular find at palatial and settlement sites, including Amarna and Malqata. The main source of cobalt ore used during this period has been identified in the Egyptian western desert, around the oases of Kharga and Dakhla. In order to better understand the chaîne opératoire of Late Bronze Age glass production and -working, in particular with regard to cobalt ore, at Amarna, chemical analysis by portable X-Ray fluorescence was carried out in the field. This was done on contextualised archaeological material excavated at the site of Amarna, which cannot be exported from Egypt for analysis. The results of this study demonstrate how cobalt ore was used in the various known workshop sites at Amarna, resulting in a deeper understanding of raw materials use and exchange across this settlement. [ABSTRACT FROM AUTHOR]

A series of pottery samples from the Iranian site Tol-e Kamin, ranging from pre-historical period to the New Elamite, were analyzed in order to study the geochemical variability of the pottery assemblage. A total amount of 168 measurements were obtained using a portable XRF device and were statistically handled. The results could successfully distinguish the geochemical composition of potteries from the chalcolithic to the New Elamite periods in the Kur River Basin. A major shift in the use of different clay sources could be detected since the Proto Elamite period and afterward, in which the carbonated and marl content clays represented by Ca, Ba and Sr shifted to clay sources with a tendency to non-carbonate silty clay Al, Ti, and Fe from a different geological background. The results stress the importance of further provenance studies to address issues of trade and exchange possibilities in southwestern Iran. [ABSTRACT FROM AUTHOR]

Cobalt was commonly used as a colourant in the Egyptian glass industries of the 18th dynasty, dark blue glass being a regular find at palatial and settlement sites, including Amarna and Malqata. The main source of cobalt ore used during this period has been identified in the Egyptian western desert, around the oases of Kharga and Dakhla. In order to better understand the chaîne opératoire of Late Bronze Age glass production and -working, in particular with regard to cobalt ore, at Amarna, chemical analysis by portable X-Ray fluorescence was carried out in the field. This was done on contextualised archaeological material excavated at the site of Amarna, which cannot be exported from Egypt for analysis. The results of this study demonstrate how cobalt ore was used in the various known workshop sites at Amarna, resulting in a deeper understanding of raw materials use and exchange across this settlement. [ABSTRACT FROM AUTHOR]

Background and objective:Toenail is an advantageous biomarker to assess exposure to metals such as manganese and mercury. Toenail Mn and Hg are in general analyzed by chemical methods such as inductively coupled plasma mass spectrometry and atomic absorption spectrophotometry. In this project, a practical and convenient technology—portable X-ray florescence (XRF)—is studied for the noninvasivein vivoquantification of manganese and mercury in toenail. Material and methods:The portable XRF method has advantages in that it does not require toenail clipping and it can be done in 3 min, which will greatly benefit human studies involving the assessment of manganese and mercury exposures. This study mainly focused on the methodology development and validation which includes spectral analysis, system calibration, the effect of toenail thickness, and the detection limit of the system. Manganese- and mercury-doped toenail phantoms were made. Calibration lines were established for these measurements. Results:The results show that the detection limit for manganese is 3.65 μg/g (ppm) and for mercury is 0.55 μg/g (ppm) using 1 mm thick nail phantoms with 10 mm soft tissue underneath. Discussion and conclusion:We conclude that portable XRF is a valuable and sensitive technology to quantify toenail manganese and mercuryin vivo. [ABSTRACT FROM PUBLISHER]

This study explores the authentication of a bronze statue by means of the evaluation of technical evidence and investigation of patinas formation. The statue was identified by the police as a product of illicit excavation and handed to the Archaeological Museum of Thessaloniki. The visual examination reveals technical features that are consistent with those commonly found on ancient bronze statues while the physicochemical character of the corrosion was in accordance with typical bronze corrosion mechanisms (decuprification). Original features like the metal microstructure were detected on the corrosion layers, showing the complexity and long lasting character of their formation. The metal composition was determined by XRF and the corrosion products were analysed by XRF and SEM-EDS. [ABSTRACT FROM AUTHOR]

Potash–lime silicate (K2O–CaO–SiO2) glass dated to the Warring States Periods is one of the earliest glass types that have been found in China, but scientific research about this type of glass is scarce at home and abroad. In the present study, a total of 23 potash–lime silicate glass samples of the Warring States Period, excavated from different areas of China, were analyzed noninvasively using a portable X-ray fluorescence spectrometer (pXRF). The chemical composition of these K2O–CaO–SiO2glasses was analyzed and compared with that of the potash silicate (K2O-SiO2) glasses of the Han Dynasties. The possible raw materials used to make the ancient K2O–CaO–SiO2glasses were discussed. It appears that the ancient K2O–CaO–SiO2glasses were produced in China and the potash glasses were of versatile origins. This research provides useful clues to trace the technical development of ancient Chinese glass. [ABSTRACT FROM PUBLISHER]

The majority of the objects found in the textiles collection at the German Historical Museum in Berlin have been treated with different biocides at various points in the past. Prior to this study, the presence of organochlorinated pesticides in rooms and storage cabinets had already been proven in an analysis of air samples that employed gas chromatography and mass spectroscopy. To estimate the risks these toxins pose to both collections and museum staff, we conducted a field study with the help of a portable X-ray fluorescence spectrometer. In this study, we present an attempt at a reliable quantitative analysis. In addition to chlorine, other potentially hazardous elements such as lead, arsenic, and mercury were found in the majority of the objects. In some cases, however, it has to be taken into account that the detected elements might have originated from manufacturing processes rather than biocide treatments. Such knowledge is a crucial prerequisite to proper risk prediction. [ABSTRACT FROM AUTHOR]

To assess the proposal that the widespread distribution of early–mid Holocene obsidian stemmed tools in Papua New Guinea signifies wide ranging social networks, studies of their morphology, technology, and geochemical composition were conducted. It is argued that strong similarities in technology and form of artifacts made from both Manus and New Britain obsidians and their characterization to only one sub-source in each region indicate significant social interaction between these two island groups. Away from the obsidian sources, stemmed tools made from local raw material as well as imported obsidian suggest knowledge and practices were also distributed through a series of overlapping social networks. Long-distance voyaging to confirm and enhance status might explain the far-flung distribution of some tools. The new data about stemmed tool production on Manus and the early use of the Umleang-Umrei sub-source highlight the importance of further research in that region. [ABSTRACT FROM AUTHOR]

Elemental analysis of welding fume samples can be done using several laboratory-based techniques. However, portable measurement techniques could offer several advantages. In this study, we sought to determine whether the portable X-ray fluorescence spectrometer (XRF) is suitable for analysis of five metals (manganese, iron, zinc, copper, and chromium) on 37-mm polytetrafluoroethylene filters. Using this filter fitted on a cyclone in line with a personal pump, gravimetric samples were collected from a group of boilermakers exposed to welding fumes. We assessed the assumption of uniform deposition of these metals on the filters, and the relationships between measurement results of each metal obtained from traditional laboratory-based XRF and the portable XRF. For all five metals of interest, repeated measurements with the portable XRF at the same filter area showed good consistency (reliability ratios are equal or close to 1.0 for almost all metals). The portable XRF readings taken from three different areas of each filter were not significantly different (p-values = 0.77 to 0.98). This suggested that the metal rich PM2.5 deposits uniformly on the samples collected using this gravimetric method. For comparison of the two XRFs, the results from the portable XRF were well correlated and highly predictive of those from the laboratory XRF. The Spearman correlation coefficients were from 0.325 for chromium, to 0.995 for manganese and 0.998 for iron. The mean differences as a percent of the mean laboratory XRF readings were also small (<5%) for manganese, iron, and copper. The differences were greater for zinc and chromium, which were present at very low amounts in our samples and below the limits of detection of the portable XRF for many of the samples. These five metals were moderately to strongly correlated with the total fine particle fraction on filters (Spearman p =0.41 for zinc to 0.97 for iron). Such strong correlations and comparable results suggested that the portable XRF could be used as an effective and reliable tool for exposure assessment in many studies. [ABSTRACT FROM AUTHOR]

The mining and roasting of the arsenopyrite ore in the Waiuta area (c. 30 km south of Reefton, Westland) has left a legacy of arsenic-rich material. The scale and extent of elevated arsenic concentrations were established with field portable X-ray fluorescence measurements. The principal source of environmental arsenic at the Prohibition Mill site is the roasting by-product arsenolite, which is very toxic and more environmentally mobile than arsenopyrite in original ore. Resultant arsenic-rich run-off (c. 30 mg/L) is temporarily immobilised by the formation of the secondary arsenic mineral scorodite, which cements the ground around the roaster system. Within the roaster system and the scorodite-rich substrate, arsenic concentrations can be up to 40 and 30 wt%, respectively, and high levels (wt% scale) can persist below 60 cm depth of the substrate. Arsenic in the soil surrounding the site can still exceed 0.1 wt%, and this arsenic is derived from atmospheric fall-out of arsenolite dust, rather than dispersion of arsenolite. The arsenolite dust in the soils has dissolved over the past 60 yr resulting in persistent elevated levels of arsenic adsorbed onto natural iron oxyhydroxide in the soil. An area of c. 32 500 m² around the Prohibition Mill site has arsenic levels above the recommended guideline for commercial/industrial sites of 0.05 wt%. On a regional scale, arsenic concentrations do not generally exceed the guideline for commercial/industrial sites, with the exception of a few localised anomalies related to arsenopyrite-rich waste rock. [ABSTRACT FROM AUTHOR]