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861.
Previous studies of colourless Romano‐British vessel glasses have suggested that, regardless of vessel type, they show considerable compositional homogeneity. Intriguing differences in variability (as opposed to mean composition) have, however, also emerged. This paper reports on a compositional study of 243 vessels, that is larger and more carefully controlled than in previous studies of this kind. Unexpected compositional differences have been found both between and within the four vessel types studied. We discuss the implications of these results in the context of different models that have been proposed for glass‐making and glass‐working in the Roman world.  相似文献   
862.
Medieval archaeological findings made of pietra ollare (basic and ultrabasic metamorphic rocks belonging to the greenschist facies) and coming from central–eastern Italy have been characterized through a petrological study (modal mineralogy, whole‐rock geochemistry, XRD and SEM–EDS analyses). The pietra ollare artefacts considered in this work consist of fine‐grained, grey to pale‐grey, magnesite‐bearing talc‐schists (i.e., soapstones). In order to determine their production centres, Alpine soapstones quarried in ancient times were selected on the basis of their mineralogical and textural compatibility with the archaeological findings. The mineralogy and chemistry (major and trace elements) contributed to establishing the ancient quarries of the Valchiavenna (central Alps) as the probable provenance area. This archaeometric investigation proves that Alpine artefacts made of pietra ollare spread to the south of the Po Plain during the Middle Ages. It can be inferred that the Alpine soapstone trade towards the Marche and Abruzzo regions was addressed through the main waterways: Lake Como, the Adda and Po Rivers and finally the Adriatic Sea.  相似文献   
863.
In recent years, several groups of archaeological metal finds from the areas around the southeastern Alps, dated between Bronze Age and Roman times, have been scientifically analysed (by ICP, AAS and/or XRF) within the framework of different projects. The data now available give a fairly good general picture of the evolution and development of metallurgy in this area and seem to indicate that the region played an important role in the exchange of objects and raw materials over many centuries. The significance of some of the metal finds, which are particularly relevant for this research, is discussed.  相似文献   
864.
In order to interpret strontium and oxygen isotope values in Neolithic human skeletons analysed previously, we begin to map the biologically available strontium, carbon and oxygen isotopic signatures of prehistoric southern Germany by analysing tooth enamel of pigs from archaeological sites distributed around the region. The mapping shows a marked upland–lowland difference in biologically available 87 Sr/ 86 Sr values, ranging between 0.7086 and 0.7103 in the sedimentary lowlands, and from 0.710 to as high as 0.722 in the crystalline uplands of the Odenwald, the Black Forest and the Bavarian Forest. In addition, carbon isotopes in the carbonate fraction of pig enamel were generally about 1–2 more enriched in 13 C in the uplands. Despite the expected depletion of 18 O with altitude, oxygen isotopes in pig enamel showed little correlation with site altitude, although for pig samples not older than the Iron Age there was some geographical correlation withδ18O patterns in modern precipitation.  相似文献   
865.
A novel luminescence methodology for dating surfaces of granitoid rocks is presented, with encouraging results for archaeological stone structures. It is based on the zeroing of the latent signal of optically stimulated luminescence (OSL) in feldspar and quartz grains of the stone surface during exposure to daylight. When after bleaching the surface is shielded from light, the OSL signal builds up again, such that its intensity provides an age for the event of the last exposure to light. This event could be the construction or the destruction of stone structures or, for example, sedimentary deposition of granitic boulders, such as in fan deposits. The experimental approach utilizes a high spatial resolution detection technique (HR‐OSL) for OSL of minerals that are left in their original petrological context; that is, without any mineral separation. With this approach, steep gradients in microdosimetry at the surface and at grain boundaries become important and are discussed in detail. The new dating technique is successfully applied to a stone wall of the medieval castle of Lindenfels in southwestern Germany and the pre‐Columbian Nasca lines (geoglyphs) around Palpa in southern Peru.  相似文献   
866.
A simple method for calculating the prevalence of disease in a past human population is described with particular reference to osteoarthritis. It can be applied to diseases other than osteoarthritis, and should prove particularly useful when studying the epidemiology of other diseases which affect numerous sites within the body and where the overall prevalence cannot be obtained simply by adding the prevalences of the individual sites, because more than one may be affected in the same skeleton. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
867.
The aim of this paper is to explore the question: why is the archaeology of English historic landscapes apparently so provincial? Inevitably the response must be that matters are more complex. In this paper, I examine the work of W. G. Hoskins, the “father of English landscape history,” and draw attention to: the complex way in which landscape is embedded in nationalism; the relations between locale, province, and nation; and the way wider tensions, in particular of colonialism are embedded within Hoskins's own discourse. In conclusion, I examine ways in which this problematic continues to structure enquiry into the English landscape today and to inhibit a genuinely international and comparative approach to historic landscapes.  相似文献   
868.
869.
870.
The Nasca culture of the south coast of Peru developed during the first millennium ad and is known internationally for its elaborately decorated polychrome pots. Despite decades of iconographic analysis, little is known about the more technological aspects of Nasca pigment production and application. We present results from a pilot study on iron isotopes as a potential line of inquiry into the differences between red and black pigments in Nasca pigments. As well, we conduct a small firing experiment to examine potential changes in isotope composition. Our analyses show three significant results. First, firing does not change the isotopic ratios of Fe in pigments. Second, red and black pigments show differences in their iron isotope composition, which relate to differences in the minerals used to make the different colors. Third, naturally available hematite samples show greater isotopic variation than pigment samples, suggesting that people selected a limited range of iron oxides to produce pigments.  相似文献   
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