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71.
Three lipid analysis methods were applied to extracts of archaeological potsherds from the ancient city of Sagalassos, south‐west Turkey. In the fatty acid methyl ester fraction, obtained by selective transesterification of acylglycerols, the ratio of methyl palmitate to methyl stearate was determined. Secondly, by means of gas chromatography– combustion–isotope ratio mass spectrometry (GC–C–IRMS), stable carbon isotope ratios were measured for the same methyl esters. Finally, triglyceride composition was determined via high‐performance liquid chromatography–mass spectrometry (HPLC–MS). All three methods can be used to trace the origin of animal fat. Agreement between them is reasonable, especially in recognizing ruminant adipose fat. One sample was found to be of dairy origin using both GC–C–IRMS and HPLC–MS. The advantages of the various methods are discussed. Variations in lipid composition were observed between samples from different periods and excavated in diverse areas within the city of Sagalassos.  相似文献   
72.
73.
87Sr/86Sr ratios have been determined for glasses from four production sites, dated to between the sixth and the 11th centuries, in the Eastern Mediterranean region. On the basis of elemental analyses, the glasses at each location are believed to have been melted from different raw materials. Two glass groups, from Bet Eli‘ezer and Bet She‘an, in Israel, are believed to have been based upon mixtures of Levantine coastal sands and natron, and have 87Sr/86Sr ratios close to 0.7090, plus high elemental strontium, confirming a high concentration of modern marine shell (87Sr/86Sr ~ 0.7092) in the raw materials. The isotopic compositions of these two groups of glasses differ slightly, however, probably reflecting a varying ratio of limestone to shell because the sands that were utilized were from different coastal locations. Natron‐based glasses from a workshop at Tel el Ashmunein, Middle Egypt, have 87Sr/86Sr values of 0.70794–0.70798, and low elemental strontium, consistent with the use of limestone or limestone‐rich sand in the batch. High‐magnesia glasses based on plant ash, from Banias, Israel, have 87Sr/86Sr values of 0.70772–0.70780, probably reflecting the isotopic composition of the soils that were parental to the plants that were ashed to make the glass. Strontium and its isotopes offer an approach to identifying both the raw materials and the origins of ancient glasses, and are a potentially powerful tool in their interpretation.  相似文献   
74.
Trace element and Sr isotope data were obtained by laser ablation‐ and solution mode‐(MC)‐ICP‐MS analysis for tooth enamel from remains excavated at the New Kingdom period Egyptian colonial and Nubian cemetery site of Tombos (Sudan). Elemental abundances determined by both methods of ICP‐MS analysis yielded comparable values; however, 87Sr/86Sr values obtained by laser ablation were higher compared to their solution mode counterparts. This discrepancy is related to the production of a molecular interference—Ca + P + O (overlaps 87Sr); hence the higher 87Sr/86Sr values recorded during ablation analyses. Laser ablation studies of enamel may provide relatively precise 87Sr/86Sr values rather quickly but cannot be used for accurately deciphering historical population migrations.  相似文献   
75.
The origin of the colorants in Egyptian glass of the second millennium BC has been the subject of much research and debate. Several colorants including lead antimonate yellow and calcium antimonate white appear in the archaeological record apparently concurrently with the introduction of glass, and it is possible that their origins are in some way linked. This paper examines the use of the antimonate colorants and uses analytical and experimental techniques to deduce possible technologies of production. Trace element data derived from a pilot study by LA‐ICPMS gives additional indications of a possible source in the Caucasus for the antimony of these glasses.  相似文献   
76.
Elemental analyses have been conducted on 61 coloured opaque glasses from the Malkata and Lisht New Kingdom glass factories. The presence of tin in several of the blue glasses suggests that a bronze casting byproduct or corrosion product was the source of the copper colorant for these glasses. A positive correlation between the lead and antimony concentrations of the yellow and green opaque glasses, plus a consistent excess of lead oxide in these glasses, suggests the use of antimony‐rich cupellation litharge as the source for the Pb2Sb2O7 , colorant in these glasses. The metallurgical byproducts used to colour the Malkata and Lisht glasses provide an explicit mechanism for Peltenburg's theory of interaction between second millennium BC glassmakers and contemporary metalworkers.  相似文献   
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