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1.
The presence of DNA has been demonstrated in the cell nuclei of an ancient Egyptian mummy fragment. When extracted, this DNA proved to be degraded to a considerable extent and chemically modified. However, the preservation of nucleic acids in this specimen suggests that applying recombinant DNA techniques to the study of ancient mummified tissues might prove to be a fruitful future area of research.  相似文献   
2.
The chemical and mineralogical characterization of seven ceramic fragments produced within Tiwanaku state (c.500–1000 ce ) is reported. The instrumental techniques used included X‐ray elemental and mineralogical chemical analysis, Raman spectroscopy, and scanning and light microscopy. The results indicate there are several clay types, although they show similarities, such as the use of a plant‐based temper. The red colour of the decoration is hematite, and manganese oxides such as jacobsite are present in the black. The white colour is a mixture of gypsum and clay, and the orange is a mixture of hematite and clay. The use of colours, the quality of the clays and the temperatures reached during pottery firing point to expertise in ceramic production and to complex decision‐making processes. The multi‐elemental archaeometric approach documented here could become an important tool to shed a light on ancient ceramic technology and the internal variance of Tiwanaku pottery.  相似文献   
3.
The results obtained from the multi-analytic compositional characterization of ceramic pastes and paints of the Santa María style, from the El Bolsón valley (Belén Department, Catamarca Province, Argentina), are presented here. This pottery style had a wide regional distribution in Northwestern Argentina between ca. 1000 and1600 ce and is characterized by its complex iconography painted in black, cream and red. The analyses show that the containers correspond to the technical tradition of using grog temper and suggest that its manufacture involved a double firing process. This reveals a new practice for the time.  相似文献   
4.
Avian egg-shell occurs fairly commonly on archaeological sites, particularly in alkaline deposits. It is rarely studied in detail. Egg-shell structure is described briefly below and features which may be of value for identification purposes are discussed. Egg-shells from 14 archaeological sites are tentatively identified as goose, domestic fowl, duck and guinea fowl. It seems likely that confident identification should ultimately be possible using a combination of features. This should yield information complementary to osteological evidence for the history of the utilization of birds and their eggs.  相似文献   
5.
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   
6.
纸张的老化程度一直是纸质文物保护中的重要研究方面,以往多采用目测法和经验来推断纸张的老化程度。纸张物理强度、聚合度等能表征老化状态的理化性能测试由于需要大量的样品而无法用于文物检测。近年来随着显微共聚焦拉曼光谱、近红外傅里叶变换拉曼光谱、表面增强拉曼光谱等技术的发展,作为一种原位、无损、微区的分析方法,拉曼光谱被越来越多地应用到了纸质文物的相关分析研究中,为纸质文物的保护修复提供科学依据。结合国内外文献,对拉曼光谱在纸张老化、碳黑颜料以及其他颜料上的应用和研究现状进行了梳理归纳。随着拉曼光谱应用的不断深入,以及与其他分析技术、化学计量学等的结合,未来将在纸质文物研究中发挥更多的作用。  相似文献   
7.
The chemical compositions and microstructures of some 35 faience objects from Egypt spanning the period from the Middle Kingdom through to the 22nd dynasty are determined using analytical scanning electron microscopy. Replicate faience beads glazed in the laboratory using the efflorescence and cementation methods are similarly investigated. In efflorescence glazing, there appears to be preferential efflorescence of soda over potash, and in cementation glazing, preferential take up of potash over soda into the glaze. These data are then used to try to infer the raw materials and methods of glazing employed in the production of the ancient faience. The glaze/glass phases present in the faience differ significantly in composition from that of New Kingdom glass. This could be due either to the use of different plant ashes or to changes in the composition of the plant ashes during the production of faience and/or glass. Although it is only rarely possible to determine with certainty whether ancient faience was glazed by efflorescence, cementation or application, the observed microstructures provide an indication of the approach adopted to achieve desired performance characteristics such as strength.  相似文献   
8.
A new lithic tool type was discovered at the Pacific Nicaraguan archaeological site of Santa Isabel (AD 800–1350) and named raspadita (small scraper). Thousands of these small tools (1–2 cm in length) were found. They have a rounded proximal edge and a pointed distal end. In this study, the raspaditas are proved to be a coherent tool class with minimal variation in size, shape, material type and usewear. They were manufactured from white chert bladelet cores using soft hammer percussion and pressure flaking unifacial retouch. Usewear points to a composite tool form and a scraping function for the raspaditas. Scanning electron microscopy determined a ventral leading, dorsal following, unidirectional scraping motion for the raspadita proximal end. The material that was scraped has still to be definitely determined but phytoliths visible in the SEM images suggest that the composite tool was used for plant processing.  相似文献   
9.
Scanning electron microscopy/energy dispersive X-ray analysis has earlier shown that the white background layer (slip) on painted pottery sherds (Yangshao culture, Henan, China, 4200 BC) is composed of kaolinitic clay containing titanium in the assumed form of TiO2 at just 1 wt%. The same samples of white slip have now been studied by Raman microscopy, revealing bands characteristic of anatase, but none from the majority species, the matrix of kaolinitic clay. These results highlight the extraordinarily intense Raman scattering from even trace amounts of anatase and thus the need to recognise that, although the colours of archaeological artefacts are almost always determined by the nature of the matrix, the Raman spectrum may be determined by a highly scattering trace component such as anatase. The significance of anatase as a potential date-marker pigment on works of art and archaeological artefacts is discussed.  相似文献   
10.
Palaeohistology as a valuable diagnostic instrument is dependent on the production of high‐quality thin‐ground sections from dry bone. The objective of this study was to consider technical differences and assess the qualitative outcomes of five techniques for preparing thin‐ground sections from dry archaeological bone. Established techniques with long follow‐up times and excellently documented results were compared with simpler and cheaper time‐saving techniques. Evaluations were made of the quality of thin sections obtained by one classical machine‐based embedding technique, two revised versions of the same technique, one manual moulding technique based on Frost's rapid technique and one manual hybrid technique. Five osteological specimens of differing quality were prepared following the manuals for these five techniques and examined microscopically with respect to a list of standardised histological and diagenetic parameters. Alterations in the specimens attributable to preparation effects were recorded, and observations were scored with reference to three criteria: section quality, technical quality and staining. The results show that embedding techniques are to prefer. Superglue should not be used as a mounting or embedding medium. Manual grinding comes with several limitations, and machine cutting and grinding are preferred. Haematoxylin staining can be successfully applied to embedded specimens, giving more information on microscopic diagenetic processes. A stepwise manual for a revision of the classical embedding technique is presented. The time required for producing sections using classical embedding techniques is shortened from 6 weeks to 3.7 days by refining the preparation/polymerization processes involved with no loss of osteological data. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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