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Determination of the Fineness of Medieval Coins—Evaluation of Methods in a Case Study of a Medieval Pfennig 下载免费PDF全文
The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed. 相似文献
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The Analysis of Late Bronze Age Glass from Nuzi and the Question of the Origin of Glass‐Making 下载免费PDF全文
This paper re‐analyses a considerable corpus of glass from the Late Bronze Age site of Nuzi, found near Kirkuk in Iraq. SEM–WDS and Sr and Nd isotopic analysis were applied, in addition to cataloguing the glass. The work showed that the glass technology at Nuzi was subtly different from contemporary Egyptian sites, using different ways of opacifying and working glass. At least two, perhaps three, Near Eastern production sites are postulated. The range of glass colours and the skill of their application at Nuzi was perhaps not on a par with the Egyptian sites. This led to a reconsideration and review of the accepted wisdom that the Near East is the source of the innovation that is glass‐making. This opinion is based on limited textual and iconographic sources and is dominated by an erroneous early date for a very developed Nuzi glass industry along with a few finds of glass vessels in early contexts. Some of this evidence has now been at least questioned, suggesting that glass‐making in Egypt, at least as early as the middle of the 15th century bc , and probably earlier, is no later than that in the Near East. It is argued that it is far from clear that the Near East was the source of the innovation and that a more cautious approach would better fit the evidence. 相似文献
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First Insights into the Technique Used for Heat Treatment of Chert at the Solutrean Site of Laugerie‐Haute,France 下载免费PDF全文
The earliest evidence of flint and chert heat treatment was found in the ~21.5–17 ka old European Solutrean culture. The appearance of pyrotechnology as part of the production of stone tools has important implications for our understanding of Upper Palaeolithic technological evolution and the specific adaptations during the last glacial maximum in Europe. However, the techniques and procedures used to heat‐treat rocks during the Solutrean remain poorly understood. No direct archaeological evidence has so far been found and the most promising approach is to understand these techniques by determining the parameters with which flint and chert were heated at that time. In this study, we investigate the heating temperature of 44 heat‐treated laurel‐leaf points from Laugerie‐Haute, using a non‐destructive technique based on infrared spectroscopy. Our results document that most of the artefacts were heated to a narrow interval of temperatures between 250 °C and 300 °C. This indicates a standardized technique that allowed to created similar conditions during successive heating cycles. The implications of these results for our understanding of the technical complexity during the Solutrean must be discussed in the light of different heating techniques used at different places and periods. 相似文献
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Improvements in Archaeomagnetic Dating in Western Europe from the Late Bronze to the Late Iron Ages: An Alternative to the Problem of the Hallstattian Radiocarbon Plateau 下载免费PDF全文
We present a new curve of the directional secular variation of the geomagnetic field in Western Europe between 1500 bce and 200 ce . Its computation relies on a Bayesian framework. The fast secular variation during the Late Bronze and Early Iron Ages makes archaeomagnetic dating efficient with a respective precision of 150–200 and 60–100 years during these periods. The Bayesian method also provides posterior date distributions that refine the dating of reference data, especially during the period of the Hallstattian radiocarbon plateau. Archaeomagnetism becomes a valuable alternative to radiocarbon and will help to improve the archaeological chronologies. 相似文献
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The recently completed Avenue of Saints (AOS) highway project in the Mississippi Valley of northeastern Missouri resulted in the documentation of Woodland period sites ranging from approximately 200 cal BC to AD 1200. This article updates the existing Woodland chronology for this locality based on new information collected during the project. Data pertaining to Early, Middle, and Late Woodland sites are presented. The approximately 1,400-year occupation span provided researchers an opportunity to view diachronic trends in tool manufacture, subsistence economy, and landscape use. Based on regional comparisons of ceramic and lithic technologies and vessel decoration, the Woodland sequence in northeastern Missouri was influenced by population movements originating from east of the Mississippi River and from southern sources in the Salt River valley. 相似文献
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Recent studies have shown that pre-Columbian societies in the Amazon undertook significant landscape modifications, including earthworks. Our fieldwork has revealed that pre-Columbian settlements in the Santarém Region, Lower Amazon, were not limited to the vicinities of permanent water courses, as formerly often assumed. Instead, numerous archaeological sites, dating from ca. a.d. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém. These upland sites have been found to be associated with particular features in the landscape: cavities or depressions, known locally as “Poços de Água”. LiDAR data shows that a pattern of non-randomly distributed depressions extends far into the densely forested Tapajós National Forest (Flona-Tapajós), allowing us to suggest that the expansion of inland settlement extended considerably farther to the south than what has previously been established through conventional archaeological fieldwork. 相似文献