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261.
Analyses of a 20–30 cm thick, completely combusted ash at the 25 × 70 m Tschudi burn at Chan Chan, northern Perú, contain 52–55 wt% SiO2, 180–210 ppm zirconium and are consistent with coal ash. Soil geochemistry across the burn showed elevated calcium and phosphorus content, possible evidence for reported human cremation. A calcined, 5 g, 4.5 cm skull fragment recovered from the burn was confirmed as human by protein radioimmunoassay (pRIA). X‐ray diffraction showed that the bone had been heated to 520°C. The burn took place c. ad 1312–1438 based on interpretation of a 14C date on carbonized plant tinder.  相似文献   
262.
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   
263.
ω‐(o‐Alkylphenyl)alkanoic acids are known to form in vitro from triunsaturated fatty acids following protracted heating. These compounds have recently been identified in absorbed lipid extracts obtained from archaeological pottery vessels, providing a potentially valuable new class of indicator for the processing of commodities, such as marine oils, which contain high abundances of polyunsaturated fatty acids. Experiments were conducted to assess whether ω‐(o‐alkylphenyl)alkanoic acids form when pure compounds and complex triacylglycerol mixtures are heated with a fired clay. The results demonstrate that ω‐(o‐alkylphenyl)alkanoic acids are only produced following heating of unsaturated fatty acids (tri‐, di‐ and monounsaturated species) or complex unsaturated fatty acyl lipids at around 270°C. Heating saturated fatty acyl lipids does not yield ω‐(o‐alkylphenyl)alkanoic acids. Thus, when searching for evidence for the processing of marine derived animal fats in archaeological pottery vessels, it is essential that: ω‐(o‐alkylphenyl)alkanoic acids of carbon length C18 and C20 should be present, ideally with C22 also detectable (if only in trace abundances), together with at least one of the three isoprenoid fatty acids (phytanic, pristanic or 4,8,12‐tetramethyltridecanoic acid).  相似文献   
264.
Three apparently well‐preserved shipwrecks dating back to Roman times were brought to light near Piazza Municipio in Naples (Italy), during the excavation for the construction of Line 1 of the subway. The shipwrecks were covered by marine sand and silt, below the water table. In order to establish the nature and the extent of wood degradation and, therefore, determine how best to preserve the shipwrecks, a diagnostic investigation was carried out. The study involved the identification of wood species, chemical characterization of the residue component and physical and micro‐morphological characterization.  相似文献   
265.
Fifth‐ to seventh‐century window glass fragments from the Petra Church in Jordan were analysed by EPMA and spectrophotometry to characterize their optical properties and chemical composition. The objective of this study was to determine the provenance of the raw glass and the secondary production procedures of the window‐panes. Judging from the material evidence, both the crown window‐panes and possibly the rectangular samples were produced through glass‐blowing techniques. The chemical data show that the assemblage forms a homogeneous group of soda–lime–silica glass of the Levantine I type. The green glass, however, has higher silica and lower soda contents than the aqua‐blue fragments. The composition of one sample suggested the recycling of Roman glass. Our results confirm the trade of glass between the Levantine coast and Petra during Late Antiquity. No colouring agents other than iron were detected. Spectrophotometry confirmed the presence of iron and showed that the window fragments absorbed light relatively equally across the visible part of the spectrum. The windows thus seem to have provided an almost colourless illumination for the sacred interior.  相似文献   
266.
Fifteen years of research in investigating the characteristics of the EPR spectra of different types of white marble from several quarries in the Eastern Mediterranean has produced an accumulation of a large number of data, and much experience. Statistical treatment of these EPR data (statistical distributions and parameter correlations), has led to the selection of 10 parameters that are useful for quarry discrimination. Apart from the EPR parameters, the maximum grain size, measured with a stereomicroscope, has been found very useful. Boxplots have been found to be very useful as a first easy visual tool for evaluating the discrimination capacity of each parameter. On the basis of these results, a new methodology for determining the provenance of an archaeological sample was developed in stages, using a different pair or combination of parameters each time. In the first stage, the Penteli, Naxos, Hymettus and Proconnessus quarries are completely separated from each other. However, overlapping occurs between the parameter fields of Paros and Proconnessus, Paros and Hymettus and between the two archaic quarries of Melanes and Apollon on Naxos. If the sample is located in a non‐overlapping area, its provenance is obvious and easily determined. If the sample lies in one of the above three overlapping areas, an additional stage is necessary, in which other parameters are used to eliminate or decrease the overlap. Despite the partial overlapping of Paros with other quarries, the famous Lychnites marble of Paros, which was quarried underground, is clearly distinguished.  相似文献   
267.
Archaeological interpretations of ancient economies have been strengthened by chemical analyses of ceramics, which provide the clearest evidence for economic activity, and comprise both the objects of exchange and its means. Pottery is often manufactured from local materials, but its compositional diversity typically prevents significant patterns of resource utilization from being identified. Centrally located and positioned on traditional shipping routes, Cyprus maintained ties with and supplied a variety of distinctive ceramic products to the major commercial centres in the eastern Mediterranean throughout Antiquity. We analysed two Cypriot .ne wares and a variety of utilitarian pottery, as well as samples of extant Cypriot clays to determine source provenance. These chemical analyses provide an objective indication of the origins of ancient (Bronze Age and Roman) ceramics manufactured on Cyprus. The distribution of the probable clay sources and the links between pottery style and the material environment also afford a perspective on the spatial organization of large‐scale pottery production on the island. Compositional analysis provides the means to assemble geographies of pottery production and to unravel the interregional system of exchange that operated in Antiquity, but the ability to accomplish these tasks is predicated on systematic analyses of ceramic products and raw materials that are found far beyond the bounds of individual archaeological sites.  相似文献   
268.
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.  相似文献   
269.
In order to obtain chimpanzee (Pan troglodytes) mastication damage on bones, cleaned, disarticulated ribs and long bones of bovids and cervids were coated with food substances found palatable by captive chimpanzees. The bones were then presented to four groups of mixed sex and mixed age chimpanzees from the Tulsa Zoo (Oklahoma) and the Southwest Foundation for Biomedical Research (San Antonio, Texas). In the process of feeding on the coated bones, the chimpanzees inflicted discernible mastication damage on 73·61% of the total recovered bone specimens. Analysis of these chimpanzee-induced bone modifications reveals that non-technological hominoids of the same approximate size and with comparable dentition and bite force to the gracile australopithecines and earliestHomoare very capable of inflicting the same range and degree of damage to bones as are feeding carnivores. This finding implies that zooarchaeologists must take a contextual (configurational) approach when analysing mastication damage on arch-aeological bones, rather than automatically attributing all such damage to carnivores.  相似文献   
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