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In this study, we have evaluated the applicability of Nd isotopic analysis for the provenancing of Roman glass and we present a database of Nd isotopic compositions of possible sand raw materials from the western Mediterranean, as a means of comparison for the growing number of isotopic studies on ancient glass. The 143Nd/144Nd isotope ratio of sands is a good indicator for their geological (and sometimes geographical) provenance. The use of the isotopic signature of Nd as a proxy for the source of silica in glass is, however, not always straightforward because of the possible overlap of signatures from different suppliers. [ABSTRACT FROM AUTHOR]

The provenancing of Roman natron glass is one of the most challenging problems in the field of archaeometry. Although the use of Sr and Nd isotope ratios and trace element signatures as an indication of provenance has proven promising, there are still many unknowns. In this study, the influence of the different raw materials on the final Sr isotopic composition of Roman natron glass is examined. It is shown that the 87Sr/86Sr ratio in natron glass is significantly influenced by the silicate fraction of the sand used and does not always provide a clear indication of the lime source used. [ABSTRACT FROM AUTHOR]

In this study analysis of major elements and Sr--Nd isotopes is performed on 33 colourless glass fragments from two Ro- man shipwrecks discovered in the Northern Mediterranean Sea, the Iulia Felix (irst half of the third century AD) and the Ouest-Embiez (end of the second--beginning of the third century AD). Two compositional groups are deined based upon the major elements analysis, suggesting the use of diferent raw materials, and possibly the production of the glass samples in two separate factories. Sr--Nd isotopes, promising indicators for provenancing geological resources used as raw materials 87 86 in glass manufacturing, conirm the compositional groups. The Sr/ Sr signature is very close to the modern sea water signature (0·7092) for all samples, likely due to the use of shell as glass raw material. The Nd signature further subdivides the compositional groups, suggesting the use of three diferent sand raw materials for the production of glass. [ABSTRACT FROM AUTHOR]

The extraction of iron(III) has been studied from chloride solutions with di(2-ethylhexyl)phosphoric acid (D2EHPA), bis(2,4,4-trimethylpentyl)phosphinic acid (CYANEX 272) and its sulfur-substituted analogs, called CYANEX 302, and CYANEX 301, and 5-dodecylsalicylaldoxime (Aloxime 800). Job's method was applied for the characterization of the iron(III) complexes dissolved in hexane. In the case of D2EHPA and CYANEX 272, a 1:1 ligand-to-metal ratio was observed, thus inferring the coordination of additional compounds. No chloride transport occurred during extraction, therefore suggesting the formation of [Fe(OH)2L] complexes. With CYANEX 302, a ratio of 2:1 was obtained, whereas for CYANEX 301, the results of Job's method indicated the presence of four extractant molecules around the metal ion. Less hydrolysis or the possible oxidation of the sulfur-substituted organophosphinic acids and the corresponding reduction of Fe(III) towards Fe(II) may explain this behavior. In the case of Aloxime 800, the formation of the [FeL3] species is suggested. A comparative study was carried out to identify the ligand-to-metal ratio of the iron(III) complexes in anhydrous circumstances. These studies showed that 1:1 ligand-metal complexes are easily formed in the case of the organophosphoric- and organophosphinic-acid extractants. A higher ligand-metal ratio may be possible, but is not always a necessary condition for iron(III) extraction. Even the coexistence of [FeCl2L], [FeClL2] and to a smaller extent [FeL3] is quite presumable in anhydrous media. Finally, FT-IR spectra as well as UV-VIS spectra of the hexane phases make it possible to gain a better insight into the complexation characteristics of iron(III). [ABSTRACT FROM AUTHOR]

To test the potential of different analytical tools to determine the geographical origin of Ethiopian coffee, 103 green arabica coffee samples from four coffee regions in Ethiopia were subjected to multi-elements and δ 13 C, δ 15 N and δ 18 O determinations. Multi-elements were determined by using inductively coupled plasma (ICP)- and X-ray fluorescence spectrometry (XRF)-based techniques, and δ 13 C, δ 15 N and δ 18 O were determined by using elemental analyzer-isotope ratio mass spectrometry. Using linear discriminant analysis, XRF-based multi-elements with and without δ 13 C appeared to be most effective in discriminating the geographical origin of coffee, giving higher classification accuracy (89 and 86%, respectively) than ICP-based multi-elements with and without stable isotopes (80%, each). These results demonstrate the potential of XRF-based multi-element profiling as a relatively fast and low-cost tool to trace the geographical origin of Ethiopian coffee. All together this study offers the proof of concept for a promising method that, upon standardization, could be used for coffee provenance authentication and fraud detection., (Copyright © 2019. Published by Elsevier Ltd.)