A PROVENANCE STUDY OF FRENCH LIMESTONE BASED ON VARIABLE SELECTION FROM COMPOSITIONAL PROFILES

The present study shows how multivariate analysis and variable selection techniques can be used in archaeological provenances studies to improve classification performances. Neutron activation analysis (NAA), in combination with stepwise linear discrimination analysis (SLDA) (capable of simultaneously performing variable selection and classification), was applied to differentiate among limestone samples from different quarries across the north of France based on their compositional fingerprint. A hierarchical classification approach was followed, aimed at progressively assigning limestone samples to more specific sources of origin, from the broadest classification units (French regions) to the narrowest ones (individual quarries). The application of the stepwise variable selection procedure to extract the most discriminating compositional variables prior to each classification development allowed us to obtain a perfect separation between the limestone categories considered at every classification stage (all samples were correctly classified and predicted in all cases). The high‐quality results obtained were even more remarkable considering the relatively small number of significant variables selected in each case using the SLDA method. An illustrative example was provided in order to demonstrate that the classification strategy proposed can actually allocate an unknown sculpture to a particular quarry of origin.     

Charcoal analysis of industrial fuelwood from medieval and early modern iron-working sites in Bilsdale and Rievaulx,North Yorkshire,UK: evidence for species selection and woodland management

Abstract

This paper presents the results of species diversity and dendrological analyses of archaeological charcoal excavated from medieval and early modern iron production sites in Bilsdale, and at Rievaulx in the neighbouring valley of Ryedale, North Yorkshire, UK. Standard methods of quantification are used to assess species diversity, sampling sufficiency and taxa presence. The assessment of dendrological features provides additional evidence for growth trends and cutting cycles analogous with cyclical woodland management, as well as environmental and growing conditions. Analysis of archaeological charcoal from four medieval bloomery furnace sites in Bilsdale, and from the site of the hammersmithy and blast furnace at the early modern iron works at Rievaulx, provide comparable data-sets which indicate a change in cutting practise and dominant species selection for industrial fuelwood occurred between the 12th- and mid-16th centuries AD. Results show that dominant species presence changed from an admixture of predominantly birch (Betula sp.) and hazel (Corylus avellana) sourced from small calibre branchwood and stemwood used in the medieval bloomery furnaces, to a dominant oak (Quercus sp.) presence from standard sources used at the Rievaulx iron works by the mid-16th century. Whilst it is uncertain whether this change in dominant species composition and the source of industrial fuelwood is related to changes in local availability, or the result of the technological transition to blast furnace processing which occurred at this time, estate records reveal a woodland management campaign was instigated to supply and maintain fuelwood supplies to the iron works at Rievaulx which coincides with the introduction of Tudor arboricultural legislation in the 1540s.     

A Novel Application of Molecular Techniques to Pacific Archaeofish Remains*

Until recently, the identification of fish bone from Pacific archaeological sites generally relied upon morphological analysis of a relatively restricted number of skeletal elements. Limited morphological variation within fish families, amongst other things, has often restricted Pacific archaeofish determinations to the level of family or, in some cases, genus. We suggest that these relatively imprecise determinations may mask important aspects of prehistoric human fishing practices and subsistence patterns. This paper describes a molecular technique that allows for more precise taxonomic determinations, initially applied to the large and diverse family of Serranidae. The technique involves extraction, amplification, sequencing and analysis of mitochondrial DNA variation in the 16s ribosomal RNA gene. Following development of protocols and primers for modern reference materials, the technique was applied to an archaeological faunal assemblage from Aitutaki, southern Cook Islands.     

A NOVEL APPROACH TO STUDIES OF PREHISTORIC EXPLOITATION OF STONE TOOL MATERIALS USING MATERIAL COMPOSITION,SURFACE MORPHOLOGY,MICROSTRUCTURE AND MECHANICAL PROPERTIES*

For a comprehensive understanding of material exploitation in prehistory, we applied advanced analytical methods to Japanese prehistoric stone tool materials. Compositions, surface morphologies, microstructures and mechanical properties of the primary lithic materials were analysed. As a result of the tests on actual Palaeolithic artefacts, preferential material selection was observed based on composition, structure and other physical properties of the materials. Homogeneous materials composed of a single type of mineral—α‐quartz—were intentionally selected for Palaeolithic tools regardless of the type of rock. These materials unexceptionally present higher hardness and strength. Moreover, materials composed of extremely fine crystal grains of ~0.1 µm in size with highest hardness and strength were selectively used for sharp‐edged blades. These results lead us to the conclusion that quantitative and objective analyses will give us precise information on prehistoric materials, which will enable us to make an analytical approach to the comprehension of prehistoric exploitation of stone materials. This could eventually complement the traditional interpretation of material exploitation based on conventional petrological classifications.