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European archaeological collections record hundreds of thousands of stone artefacts from the Early Middle Ages described as whetstones. However, traces of non-ferrous metals, including precious metals preserved on a number of such artefacts. Many of the finds served in fact as touchstones – tools to test the quality of a particular metal. These artefacts are concentrated mainly in Vendel and Viking Age and Slavic coastal settlements and trade centres in the Baltic Sea basin, the coast and islands of Northwestern Europe, at Central and Eastern European fortresses and suburbia. Many finds also come from rural settings. In early medieval graves the touchstones join balance scales and weights as a sign of the buried individual’s access to precious metals. Especially the rural finds with traces of precious metal provide a strong reason for a revision of present views on the social stratification of the early medieval society in Europe. Chemical microanalysis allows identifying the composition of the alloys. Besides new perspectives on the fields of the social history and the circulation of precious metals, the method also provides new information for the field of archaeometallurgy.  相似文献   
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The Mfolozi and Hluhluwe Valleys of southeastern Africa are representative of a sub-tropical biome and have archaeological evidence for farming settlement spanning more than 1500 years. By collecting information on soils and plant communities within the same sample frame as archaeological data, the relative importance of environmental and anthropomorphic influences can be assessed. It is argued that, although climate and soils have determined the overall distribution of plant communities, human land use has had a considerable effect on the composition of both woodland and grassland. The nature of this interaction between man and environment provides inferential data on prehistoric economies and also aids the formulation of conservation policies in protected areas.  相似文献   
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ABSTRACT

In this paper, we review the contributions of Alan Wilson to geography and regional science over a period of more than 50 years. Beginning from theoretical insights, mathematical models and spatial analytics methods for cities, the research becomes somewhat more applied in the 1980s. The notable impact of this work in a business and commercial setting is in marked contrast to a relative lack of traction in a public policy environment. Reasons for this are explored. In more recent times, the advent of big data has started to generate transformational approaches to geographical problems. We argue that years of accumulated experience from the study of more abstract problems within less well-instrumented systems was a precursor to this. Finally, we argue that through working with a ‘family’ of modellers, the skills available to meet these challenges is significantly more extensive than could have been the case in the absence of such a programme. It is a legacy which is at once inspiring, durable and hugely significant.  相似文献   
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