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91.
The interpretation that a rock has been subjected to cultural utilization is a basic element of hunter-gatherer research. The fracture mechanics of the flaked stone tool production process are well understood and the material residues are routinely identified during fieldwork. Conversely, non-percussion processes such as hot-rock technology, which can result in rock fracture, are less well understood. An experimental study has been developed to examine the fractured gravels observed at a prehistoric site on the Southern Plains (USA). The experiment has sought to determine whether cultural or natural agencies were responsible for the production of the angularly fractured rocks. The positive results of the experiment indicate that not only were humans most likely responsible for the breakages, but also that the fractured rocks often exhibit distinctive morphologies that may be identified during fieldwork. This simple experimental methodology is applicable to other hunter-gatherer sites where the depositional environment is not conducive to the structural preservation of features such as hearths.  相似文献   
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Until the 19th century, most pigments were based on naturally occurring colored minerals and dyes, with three significant exceptions: Egyptian Blue, Chinese Blue/Purple and Maya Blue. The former two are alkaline-earth copper silicates, and because of this similarity it has been proposed that the Chinese pigments were derived from Egyptian Blue. Herein, we analyzed clumps of pigment from the Qin warriors and discovered that in spite of the structural similarity to Egyptian Blue, the micro-structural morphology of Chinese Purple is very different. Therefore, we believe that the synthesis technology for the Chinese pigments was a by-product of high-refractive index glasses (artificial jades) produced by Taoist monks. Further, the disappearance of these pigments from Chinese art and monuments concurrently with the decline of Taoism not only substantiates the link between the two, but also gives a striking example of how cultural changes in the society affected the scientific developments in ancient China.  相似文献   
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The archaeological evidence of more than a dozen ancient shipwrecks indicates that the tradition of placing a coin inside the mast-step of a ship's hold probably originated with the Romans. The mast-step coin phenomenon, which persisted through the Middle Ages and continues in various forms today, has often been characterized according to the modern concept of 'luck'. The custom was, however, not one of an exclusively maritime nature; rather, it was ultimately derived from a long-standing religious tradition that can be traced back to the consecration of the earliest Greek temples.
© 2007 The Author  相似文献   
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Teeth are often the preferred source material for isotopic and genetic assay involving ancient biomolecules. The assumption is that dental tissue preserves better due to its anatomically protected location, the enamel cap, and lower porosity compared to bone. However, this assumption has not been widely tested. Some similarities in diagenetic processes are to be expected due to similarities in structure and chemical composition of dentine and bone. This has led to the suggestion that bone can be used as an indicator of dental preservation, as a pre‐screening technique in the selection of suitable samples for biomolecular studies. Thus, direct testing of the correlation between bone and tooth preservation and diagenesis is needed. This paper reports the results of the histological characterization of diagenetic alterations within 25 human femur–tooth pairs, from a Medieval to modern (AD 1850) cemetery in Eindhoven, the Netherlands. The results showed that teeth do indeed preserve better overall, but not always, and that this was dependent on the main diagenetic factor(s) at the burial location. Furthermore, good correlations are found between the microstructural preservation of bone and teeth; similar processes of decay were observed within bone and teeth of the same individual. Overall, the study demonstrated that histological analysis of bone is useful for the identification of degradation processes that affect biomolecular preservation in skeletal material. In this way, sample selection and analytical strategies can be optimized. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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The alveolar bone condition of 34 pre-seventeenth century Solomon Island Polynesians aged 20–35 years was investigated from dental remains. The distance between the cementoenamel junction and the alveolar crest (CEJ-AC distance) was measured for six index teeth. The mean CEJ-AC measurements for each tooth, which ranged from 3.9 to 7.9 mm, greatly exceeded the distance of 2 mm frequently cited as representative of teeth supported by healthy bone. Many pathological bony defects were seen, suggestive of episodes of acute periodontitis with remissions to a quiescent phase.  相似文献   
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