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Publication date: December 2016Source:Journal of Archaeological Science, Volume 76 Author(s): Jean Milot, Franck Poitrasson, Sandrine Baron, Marie-Pierre CousturesProvenance studies of iron artefacts have become an important topic in archaeology to better understand the socio-economic organization of ancient societies. Elemental and isotopic tracing methods used so far for iron metal provenance studies showed some limitations, and the development of new additional tracers are needed. Since the last decade, the rise of cutting edge analytical techniques allows for the development of new isotopic tools for this purpose. The present study explores for the first time the use of iron isotopes analyses as a potential method for ancient iron metal tracing. Ore, slag and metal samples from two experimental reconstitutions of iron ore reduction by bloomery process were collected. Their Fe isotope compositions were measured by Multi Collector – Inductively Coupled Plasma – Mass Spectrometry (MC-ICP-MS) to assess the possible impact of smelting on the Fe isotope composition of the metal produced. Our results show that the iron isotope compositions of the slag and metal are for 8 out of 9 samples analyzed undistinguishable from that of the starting ores. This suggests that overall, no significant Fe isotope fractionation occurs along the chaîne opératoire of iron bars production, even if slight isotopic differences might be found in blooms before refinement. This fact, combined with the natural isotopic variability of iron ores, as reported in the literature, may allow the use of Fe isotopes as a relevant tracer for archaeological iron metals. This new tracing approach offers many perspectives for provenance studies. The combination of elemental and Fe isotope analyses should thus be useful to validate origin hypotheses of ancient iron artefacts.

Publication date: December 2016Source:Journal of Archaeological Science, Volume 76 Author(s): Lars Fehren-Schmitz, Joshua Kapp, Kim Laura Ziegler, Kelly M. Harkins, Gary P. Aronsen, Gerald ConlogueThe application of radiographic imaging methods like conventional X-Ray and computed tomography (CT) in bioarchaeological research is normally considered to be non-invasive. While this holds true on the macro- and microscopic level, little is known about potentially induced damage on the molecular level that could inhibit the successful recovery of ancient DNA (aDNA) from such specimens. Although there has been speculation concerning possible damage to DNA recovered from ancient remains following exposure to radiation, little research has been published. Past studies attempted to determine the specific effect of X-ray and computed tomography on the amplification of DNA from bone of recently butchered animals. Although the results suggested exposure to clinical level of radiation decreased the recovery of aDNA, the un-dehydrated state of the samples might have biased the results. In this study we utilized dry human archaeological bones from nine prehistoric and historic individuals and exposed them to different levels of radiation using conventional X-ray to more accurately examine the issue. Employing Next Generation Sequencing (NGS) of shotgun sequencing libraries, quantitative PCR (qPCR), and multiplex PCR of autosomal genetic markers we show that neither the exposure to conventional X-ray dosages (moderate irradiation) used in archaeological imaging studies nor 20-fold increased dosages (strong irradiation) have a significant effect on the quantity and quality of DNA that can be recovered from these ancient specimens. We conclude that the application of radiographic imaging methods in bioarchaeology does not impair the success of subsequent aDNA studies if simple precautions are followed.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Ellery Frahm, Gilliane F. Monnier, Nicolas A. Jelinski, Edward P. Fleming, Brian L. Barber, Justice B. LambonThe Bremer Site lies along the shores of Spring Lake in southeastern Minnesota, and excavations in the 1950s uncovered evidence of Woodland and Mississippian occupation phases. In 2011, a new program of systematic survey and excavation began to better understand cultural patterning and diachronic changes at the Bremer Site. The investigations came to include microarcheaological methods, including sediment micromorphology and soil chemistry. No element has received more archaeological attention than P, which can reflect human and animal waste, organic refuse, burials, and ash. There has been interest in integrating soil chemistry into the workflow of fieldwork and in the potential of portable analytical instruments to yield data within the timeframe of an excavation season. The last few years have seen the rise and proliferation of portable XRF (pXRF) instruments in archaeological studies. The newest generation of pXRF instruments is able to quantify P at low concentrations, and our focus here is developing effective methods to do so in archaeological soils and sediments. Using sediments from the Bremer Site, we evaluate two preparation techniques in order to find which one best balances analytical quality and preparation time. To analyze as many specimens as possible during an excavation season, it is desirable to identify adequate preparation methods as well as the smallest number of analyses needed to attain reasonable confidence levels. Regarding repeatability, we show that, to attain P values with a standard error better than 10% or 20% of the mean, one or two analyses per specimen are sufficient in a majority of cases. Regarding reproducibility, we compare the pXRF data to two independent ICP-OES datasets. Ultimately, these tests aid in establishing methods that enable archaeologically significant pXRF analyses of soil P concentrations, even when working far from an analytical laboratory.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Jordan Pickett, John S. Schreck, Renata Holod, Yuriy Rassamakin, Oleksandr Halenko, Warren WoodfinThe present work introduces the first architectural energetics analysis of a medieval tumulus from the Eurasian/Pontic steppe. In contrast to New World earthworks, tumuli on the steppe were constructed 1) with sod taken from the environment immediately surrounding the construction site, 2) with the use of draft animals and metal tools, and 3) in identifiable phases as part of funerary rituals over a period of weeks or months. These variables introduce problems which are confronted through 1) the application of novel historically attested rates for construction and 2) the creation of new, replicable mathematical methods for modeling materials transport.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Olivia RiveroThis paper presents the results of the statistical analysis of 280 pieces of Cantabrian and Pyrenean Middle Magdalenian portable art. Particular technical traces left on the medium by the act of engraving were identified through microscopic analysis and used to build a quantitative estimation of the overall technical aptitude of the engraver. Some traces considered as accidents or errors in the tracing were counted negatively, whereas others reflecting control of the tool and mastership in the use of various techniques were counted positively. A multivariate analysis based on this quantitative index, along with criteria including the type of medium was carried out using Correspondence Factor Analysis and completed with relevant statistical tests. The analysis clearly distinguishes three groups of pieces: those with a negative index, those that present a low positive index resulting from a balance between positive and negative traces, and those with a highly positive index.These different categories of pieces may be tentatively assigned to different levels of experience in tool control and engraving techniques. The mean value of the technical index seems to be correlated with the type of medium and differs significantly in the various sites studied in the corpus. These data allow us to pose some hypotheses concerning the transmission of knowledge in Magdalenian societies, such as differential access to raw materials according to the engraver’s experience, and different functionality of sites based on their production of decorated objects.

Publication date: Available online 14 October 2016Source:Journal of Archaeological Science Author(s): Hannah J. O’Regan, Angela L. Lamb, David M. WilkinsonFungi are a common part of modern human diets, but are rarely discussed in an archaeological context. Power et al. (2015) published data on bolete spores in human tooth calculus, suggesting that Upper Palaeolithic peoples ate mushrooms. Here we briefly consider the likelihood of mushroom consumption in the past, and examine whether or not stable isotopes may provide a way of seeing this in archaeological populations. We also consider the complexities of fungal stable isotopes using our own data and that from the literature. We conclude that fungi are highly variable isotopically, and are an additional dietary factor that should be considered when trying to interpret ‘terrestrial’ carbon isotope signatures combined with relatively high nitrogen isotope values in humans and other animals. Substantial mushroom ingestion could, in some cases, result in isotope values that may be interpreted as considerable meat consumption.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Alicia Grealy, Kristina Douglass, James Haile, Chriselle Bruwer, Charlotte Gough, Michael BunceTaxonomic identification of archaeological fish bones provides important insights into the subsistence practices of ancient coastal peoples. However, it can be difficult to execute robust morphological identification of fish bones from species-rich fossil assemblages, especially from post-cranial material with few distinguishing features. Fragmentation, weathering and burning further impede taxonomic identification, resulting in large numbers of unidentifiable bones from archaeological sites. This limitation can be somewhat mitigated by taking an ancient DNA (aDNA) bulk-bone metabarcoding (BBM) approach to faunal identification, where DNA from non-diagnostic bone fragments is extracted and sequenced in parallel. However, a large proportion of fishing communities (both past and present) live in tropical regions that have sub-optimal conditions for long-term aDNA preservation. To date, the BBM method has never been applied to fish bones before, or to fossils excavated from an exposed context within a tropical climate. Here, we demonstrate that morphologically indistinct bulk fish bone from the tropics can be identified by sequencing aDNA extracted from 100 to 300 ya archaeological midden material in southwest Madagascar. Despite the biases of the approach, we rapidly obtained family, genus, and species-level assemblage information, and used this to describe a subset of the ichthyofauna exploited by an 18th century fishing community. We identified 23 families of fish, including benthic, pelagic, and coral-dwelling fishes, suggesting a reliance on a variety of marine and brackish habitats. When possible, BBM should be used alongside osteological approaches to address the limitations of both; however, this study highlights how genetic methods can nevertheless be a valuable tool for helping resolve faunal assemblages when morphological identification is hindered by taphonomic processes, lack of adequate comparative collections, and time constraints, and can provide a temporal perspective on fish biodiversity in the context of accelerated exploitation of the marine environment.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Robyn Veal, Lorna O’Donnell, Laura McParland‘Reflectance’ is a method that estimates the absolute burn temperature of charcoal from the ‘shininess’ of resin mounted samples. The method’s usefulness for archaeological charcoal is yet to be comprehensively studied. This article details first results from reflectance testing of archaeological charcoals excavated from Irish Bronze Age cremations, which included calcined bone. As calcination of bone commences at 650 °C, it was expected that the charcoals would reflect at least this temperature. This was not the case for taxonomically identified charcoals >2 mm, nor for micro-charcoals of c. 250 μm, although measured temperatures rose slightly with decreasing fraction size of charcoal remains. Depositional practice, combustion completeness and taphonomic influences may have all played a part in this result, and these will need careful consideration in different archaeological circumstances. However, the greatest challenge for reflectance of archaeological materials lies in obtaining full agreement on the production and use of reflectance calibration curves. Current calibration curves differ substantially, by 100–150 °C ( ±50–75 °C) and in one instance up to as much as 180 °C ( ±90 °C). Without better agreement on calibration, the method’s ultimate usefulness in archaeological research will be limited. At the level of refinement currently possible, it will still be useful for determining very high or very low temperature processes, and possibly the difference between charcoal fuel and raw wood fuel fires. The latter has distinct implications for estimating ancient forest wood consumption, since more wood is consumed in processes employing charcoal fuel. Proving the utility of reflectance for archaeological purposes may also require modification of normal practice for archaeological field collection of charcoal, to include collection and laboratory processing of un-sieved soil samples.

Publication date: November 2016Source:Journal of Archaeological Science, Volume 75 Author(s): Matt Phelps, Ian C. Freestone, Yael Gorin-Rosen, Bernard GratuzePalestine and Egypt supplied the Mediterranean and Europe with virtually all of its glass for most of the first millennium CE. While the Muslim conquest in the 7th century saw major political and economic adjustment, immediate changes to material culture appear to have been minimal. This paper examines the impact of the Byzantine-Islamic transition on the natron glass industry of Palestine from the 7th to 12th century. A series of 133 well-contextualised glass vessels from selected excavations in modern day Israel have been analysed for major, minor and trace elements using LA-ICP-MS. These glasses are assigned to previously established primary production groups, allowing the elucidation of the chronology of key changes in glass production in the region. Results indicate a relatively abrupt compositional change in the late 7th – early 8th centuries, covering the reforming reigns of al-Malik and al-Walid, which marks the end of “Byzantine” glass production and the establishment of the furnaces at Bet Eli’ezer. At about this time there was an influx of glass of an Egyptian composition. Production of Bet Eli’ezer type glass appears to have been limited to a short time span, less than 50 years, after which natron glass production in Palestine ceased. Plant ash glass is first encountered in the late 8th-early 9th century, probably as a result of reduced local natron glass production creating the conditions in which plant ash glass technology was adopted. Egypt continued to produce natron glass for up to a century after its demise in Palestine. It is reasoned that the change and then collapse in natron glass production in Palestine may well have been as a consequence of a reduction in the quantities of available natron. This affected Palestine first, and Egypt up to 100 years later, which suggests that the factors causing the reduction in natron supply originated at the source and were long term and gradual, not short term events.