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281.
The wall paintings of Al Qurna in Egypt were studied by means of XRD and ICP–AES in order to determine their mineralogical and chemical composition, and to evaluate the impact of soluble salts on their deterioration, including the identification of the building materials and pigments used. Soluble salts analysis showed that NaCl is the most common soluble salt in the bedrock, ground water and surface water samples. The building materials are affected by the ground water, while the wall paintings in the area are affected by the Upper Egypt climatic conditions, which were studied in order to detect their role in the deterioration cycle in the area.  相似文献   
282.
Visible spectra, composition from SEM/EDX and solid‐state electrochemical data are correlated for a set of 12 Maya Blue samples from different archaeological sites of Campeche and Yucatán (Mexico). In addition to indigo and dehydroindigo, indirubin and other possibly indigo‐type compounds can be detected in Maya Blue samples. Application of hierarchical cluster analysis techniques allows similarity relationships to be established between samples from different sites, confirming prior results which suggest that the preparation of Maya Blue pigment evolved with time during the Maya culture following a ramified scheme.  相似文献   
283.
An analytical study of First Nations painted objects from the Northwest Coast showed that green earth (celadonite) was used as a green pigment by Tlingit, Haida and Tsimshian artists. Green earth appears to have been used less frequently by Heiltsuk and Kwakwa ka ’wakw artists and was not found on Coast Salish or Nuu‐chah‐nulth objects. Microscopical samples of green paint from 82 Northwest Coast objects, as well as several pigment sources and mineral specimens, were analysed using Fourier transform infrared spectroscopy or X‐ray diffraction. Green earth was the most frequently identified green pigment, found in approximately 40% of the samples.  相似文献   
284.
Numerous marble artefacts were among the extraordinary findings excavated at the Roman burial area of Faschendorf (Carinthia, Austria). The provenance of marble objects, particularly in the Roman provinces, is mostly unclear. Predominantly Mediterranean marbles have been used, but there are also some marble occurrences in the eastern Alpine regions that were exploited in those times. Besides a mineralogical–petrographic analysis, grain‐size evaluation in particular, and the determination of carbon and oxygen isotopes allow an effective characterization of the Faschendorf materials. Their provenance from the Gummern Marble complex in Carinthia is very likely.  相似文献   
285.
Few archaeological sites can claim a more celebrated position than Megiddo, the Armageddon of biblical revelation. Guardian to a strategic pass on the ancient land bridge that traverses the region, it has long been known that Megiddo played a prominent role in the emergence of the Iron Age nation‐states of biblical fame. Given its pivotal location, Megiddo provides an ideal opportunity to examine the experience of a community that found itself at the centre of these developments. The archaeological and textual evidence indicates a community that enjoyed extensive contact with an array of culturally distinct sociopolitical groups emerging in its hinterland. To further explore the nature and extent of this interaction, an assemblage of 86 ceramic sherds was analysed by instrumental neutron activation analysis (INAA). This paper presents the results of this analysis, together with an evaluation of potential geochemical and archaeological interconnections. Based on this comparative analysis, implications are drawn regarding Megiddo's role in the changing cultural and political landscape of this formative period in the history of the region.  相似文献   
286.
Seventeenth‐century opaque red (redwood) glass trade beads of different shapes and sizes were made of mixed alkali (mainly soda)–lime glasses and were coloured with Cu, presumably as cuprous oxide or as finely dispersed elemental Cu. During the early 17th century, beads of all shapes were opacified with Sn; cored beads, with uncoloured cores and hence lower Cu levels, also tended to have slightly lower Sn contents than uncored beads. By the mid‐17th century, cored tubular beads were being opacified with a combination of Sn and Sb, a technological change similar to that observed in white glass trade beads, while uncored redwood beads appear not to have been opacified with either Sn or Sb. Bead chemistries are sufficiently different to allow them to be sorted into subgroups, which may then be tracked in various archaeological sites and regions.  相似文献   
287.
In western North America, models from foraging theory have been used to address subsistence change using archaeological faunas. Several studies have argued that return rates from foraging declined in a variety of late Holocene contexts and support this position by applying a method involving the computation of a relative abundance index (AI) of large bodied animals to the sum of large and small ones. We present the results of a series of computer simulations devised to identify the relationship between changes in such indices and changes in a forager's average return rate and discuss the implications of these simulations in light of our current work in the Little Boulder Basin Area of north-central Nevada. These include, (1) the importance of using knowledge of both post-encounter return rates and changes in AI s to make inferences about changes in overall return rates; (2) the fact that there are good reasons to expect AI values to be low; and (3) what factors might contribute to the high AI values observed at archaeological sites.  相似文献   
288.
The probability of nuclei capturing neutrons reveals sharp peaks, so‐called ‘resonances’, which occur at neutron energies that are specific for each element. These resonances are very suitable for analysing the elemental composition of objects. They are the basis of a new analytical method, ‘neutron resonance capture analysis’ (NRCA). This is a fully non‐destructive method, which is applicable to almost all stable isotopes, determines the bulk elemental composition, does not require any sample preparation and results in a negligible residual activity. Recently, NRCA has been applied in a study of a series of bronze statuettes, obtained from the National Museum of Antiquity in Leiden (NL).  相似文献   
289.
Sixty‐one ceramic samples collected in Cuenca, Ecuador, were analysed by neutron activation analysis in an attempt to establish their elemental compositions. The bulk of the samples were manufactured in the region of Cuenca, with others imported from Quito in the northern highlands of Ecuador, from Panama Vieja in Panama, and from Seville in Spain. Relative to the Cuenca ceramics, the Spanish samples were separable primarily by their high Ca contents; the Panamanian ceramics by their high Cs contents; and the Quito ceramics by their high Na contents. The ceramics made within the region surrounding Cuenca are much more difficult to separate, with Ba and other elements being potentially important.  相似文献   
290.
An extensive study of the composition and microstructure of celadon and whiteware sherds excavated at Sori, one of the most important sites that were active during the founding stage of the stoneware and porcelain industry in Korea, was carried out. The analysed sherds were organized according to four different levels of the excavation and four different styles of haemurigup foot rim. Principal component analysis of the chemical compositions of the sherds revealed slight differences in their body and glaze compositions between the levels of excavation. Porcelain stone with high silica and low aluminium contents was generally used as the body material and wood ash as the chief flux in the glaze. Over the period of operation, the aluminium content in the bodies of the ceramics decreased and the P2O5 content in the glazes increased. Glazed bodies were fired in a single step, in contrast to the two‐step method used in later ceramic production. Firing conditions were adjusted to produce vitrification of the glazes, which meant that vitrification of the ceramic bodies occurred to varying extents, mostly determined by the relative contents of flux in the body and the glaze.  相似文献   
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