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81.
L. Chiarantini M. Benvenuti P. Costagliola M.E. Fedi S. Guideri A. Romualdi 《Journal of archaeological science》2009
Populonia is commonly regarded as one of the most important iron working centres in Europe in the 1st millennium BC. However, multiple layers of copper slags have been recently discovered at the bottom of the slag deposit occurring along the shoreline of the underlying Baratti Gulf. Copper slag layers have been radiocarbon dated to the 9th–8th centuries BC, i.e. to an early metallurgical stage predating the later large-scale iron production. The overall features of copper slags indicate a single-step smelting process of copper-rich ores containing variable amounts of Zn and Pb. Chemical and textural features of copper slags indicate an optimised, high-efficiency metallurgical process. 相似文献
82.
In this paper, analyses of some unusual slag samples from the prehistoric site of Tepe Hissar in northeastern Iran are presented. These slags are the remains of a five-thousand-year-old pyrotechnological process that produced speiss, a quasi-metallic material usually formed as an accidental by-product of copper or lead smelting. We argue that the “speiss slags” from Tepe Hissar suggest the intentional production of iron–arsenic alloy (“speiss”) in prehistory. Why the Tepe Hissar metalworkers produced speiss is a question that requires further investigation, but our preliminary assessment suggests that it was to provide arsenic as an alloying component for arsenical copper, the preferred copper alloy during much of the Early Bronze Age in Iran, and widely used across the ancient world. This recognition significantly advances our understanding of the early stages of metallurgy in the Old World. 相似文献
83.
In traditional Bantu-speaking societies in southern Africa, drought is caused by breaches in rules of pollution. At times of severe drought (3–5 consecutive seasons), rainmakers ascend special hills to perform special rituals. The archaeological signature of this unique activity forms a cultural proxy for drought. New research shows that burnt daga structures also correlate with high δ15N values for small stock. Burnt structures thus form a new component to the proxy. According to the ethnography, farmers implicated in the cause burnt their grain bins, and sometimes houses, as a ritual of cleansing. The dating of these structures provides a revised climatic sequence for the plateau portion of the summer rainfall region. Among other new results, there was a drought at the end of the Mapungubwe period (ca. AD 1300). At about AD 1650, droughts associated with the arrival of maize caused people to stop growing it as food for a while. 相似文献
84.
A large systematic dye investigation of prehistoric Danish and Norwegian bog textiles was carried out using high performance liquid chromatography with photo diode array detection. After the selection of the most suitable protocol for dye extraction and HPLC analysis for this specific group of archaeological samples, the second part included the characterisation of the dyes detected in the whole series of the Early Iron Age textiles and the interpretation of the dyeing technology. Natural organic dyes were found from the three main categories of natural dyes, hence throwing new light on the use of biological dye sources in Early Iron Age Scandinavia. The results clearly indicate that most Scandinavian peat bog textiles originally were dyed and that already during the 1st millennium BC, the populations in Scandinavia were familiar with the dyeing technology. 相似文献
85.
Chloë N. Duckworth Julian Henderson Frank J.M. Rutten Kalliopi Nikita 《Journal of archaeological science》2012
Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is applied to the study of four samples of opaque glass of Late Bronze Age date. The technique is uniquely capable of identifying compositional heterogeneity at a sub-micron resolution within the crystalline opacifiers dispersed through homogeneous glass matrices. It is shown that this provides crucial information on the possible raw ingredients of the opacifying inclusions used, and has the potential for highlighting regional variations in the production technology involved in creating different colours of opaque glass. 相似文献
86.
We conducted experiments to compare the micromorphological signatures of modern burnt sedge and grass bedding to laminated layers of carbonized material and phytoliths in Middle Stone Age deposits at the shelter, Sibudu. The experiments were designed to clarify the formation processes associated with the laminated layers and to investigate whether these previously identified layers of bedding were deliberately burned or not. The results indicate that the laminated layers were most likely produced by human activity related to the construction, maintenance and burning of bedding. Furthermore, our experiments demonstrate that large volumes of vegetal material could have produced the relatively thin, archaeological deposits of burnt bedding. 相似文献
87.
88.
89.
Jayd Hanna Abigail S. Bouwman Keri A. Brown Mike Parker Pearson Terence A. Brown 《Journal of archaeological science》2012
Excavations at Cladh Hallan, a Bronze Age-Iron Age settlement on South Uist in the Outer Hebrides off the west coast of Scotland, revealed the skeletons of two adults, a sub-adult and a child buried beneath the foundations of three roundhouses. Osteological and isotopic evidence has shown that the male adult skeleton is a composite made up of parts of at least three different individuals. To test the hypothesis that the female skeleton was also a composite we examined ancient DNA from four of its components: the skull, mandible, right humerus and right femur. Seven polymerase chain reactions (PCRs) were attempted, these covering positions 15,996–16,420, 16–132 and 232–368 of the mitochondrial DNA hypervariable I and II regions. Three PCRs were successful for each sample and a total of 55 sequences were obtained from the cloned products. After exclusion of possible contaminating sequences, the remaining 34 were compared. It was concluded that the mandible, humerus and femur come from different individuals. Insufficient data were obtained to draw conclusions regarding the origin of the skull. The presence of two composite skeletons at Cladh Hallan indicates that the merging of identities may have been a deliberate act, perhaps designed to amalgamate different ancestries into a single lineage. 相似文献
90.
A pre-Columbian (ca. AD 500–1500) fishery baseline is established for Anguilla, British West Indies from analyses of the remains of captured fishes from five archaeological sites. The zooarchaeological fishery baseline shows pre-Columbian communities captured diverse fishes, many of which are vulnerable to overexploitation. Composition of the captured fish community varies by site underscoring the potential importance of including samples from sites located adjacent to different marine habitats. Analyses of abundance–biomass relationships, community trophic structure, fish size and taxonomic composition indicate the Anguillian pre-Columbian fishery and coral reef ecosystem was healthy and sustainable. By providing a thorough baseline of Amerindian use of fishes on Anguilla, we provide a foundation that aids researchers asking questions about long-term change in Caribbean coral reef fisheries. 相似文献