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Publication date: October 2017Source:Journal of Archaeological Science, Volume 86 Author(s): Fadi Hajj, Anne Poszwa, Julien Bouchez, François GuéroldDifferent approaches are used to study wood provenance, but most of them are based on tracers in wood that are generally controlled by climatic factors. The strontium isotopic ratio 87Sr/86Sr in trees and soils is related to the signature of the local bedrock. Despite being used in diverse archaeological studies, Sr isotopes have rarely been used to trace the provenance of archaeological wood and especially wood from shipwrecks. In addition, recent analytical advances have allowed the detection of mass-dependent fractionation of Sr isotopes during biogeochemical processes, as reflected in the variation of δ88/86Sr values between different environmental materials. The δ88/86Sr values could be used in conjunction with the 87Sr/86Sr isotope ratio to improve constraints on the sources of Sr in the archaeological materials being studied. This paper discusses the potential and limitations of using both of these Sr isotope ratios to trace the provenance of wood from shipwrecks. We review the 87Sr/86Sr and δ88/86Sr variations in rocks, waters, soils, plants and other living organisms and discuss how to determine the local Sr isotopic signature of potential sites. We also compile a list of known wood post mortem modifications in seawater. Possible implications in terms of the modification of the original Sr isotope ratios of wood during storage in seawater are illustrated through preliminary observations. This paper points out some limitations and perspectives for using Sr isotopes in provenancing wood from shipwrecks, and suggests future research to test and apply this approach for tracing the origin of archaeological wood.

Publication date: October 2017Source:Journal of Archaeological Science, Volume 86 Author(s): Manuel Domínguez-Rodrigo, Palmira Saladié, Isabel Cáceres, Rosa Huguet, José Yravedra, Antonio Rodríguez-Hidalgo, Patricia Martín, Antonio Pineda, Juan Marín, Clara Gené, Julia Aramendi, Lucia Cobo-SánchezA series of experimental cut marks have been analyzed by eleven taphonomists with the goal of assessing if they could identify similarly 14 selected microscopic variables which would identify those marks as cut marks. The main objective was to test if variable identification could be made scientifically; that is, different researchers using the same method and criteria making the same assessment of each variable. This experiment shows that even in researchers trained in the same laboratories and following the same protocols divergences in the perception of each variable are significant. This indicates that mark perception and interpretation is a highly subjective process. If this basic analytical stage is subjective, subjectivity permeates to a greater degree the higher inferential stages leading from mark identification to reconstruction of butchering behaviors based on mark frequencies, mark anatomical distribution, actor-effector-trace processes, and statistical interpretations of the stochastic mark-imparting butchering processes. Here, we emphasize that the use of bone surface modifications for behavioral interpretations remains a non-scientific endeavor because of lack of independent replicability of criteria and processes, divergences in how variables are selected and used and epistemologically flawed analogs. This constitutes a major call to taphonomy to engage in more scientific (i.e., objective) approaches to the study of bone surface modifications for taphonomic inference elaboration.

Publication date: October 2017Source:Journal of Archaeological Science, Volume 86 Author(s): Michelle Rae BebberThe addition of pottery additives (temper) provides both production-based benefits gained during the initial vessel formation phase, and performance-based benefits associated with post-firing vessel daily use. This paper presents the results of a controlled archaeological experiment designed to assess the opportunity costs associated with the addition of temper to clay during prehistoric pottery production sequences. Specifically, this study builds upon earlier research using material science methods to more broadly assess whether vessel strength is sacrificed by the addition of temper into the clay body. Standardized experimental ceramic test specimens, based directly upon petrographic analysis of archaeological samples from a regional context (South Central Ohio, USA) and produced using glacially-deposited illite-based clay, were subjected to mechanical strength tests using an Instron Series IX universal testing machine. The results demonstrate that there are indeed opportunity costs associated with temper addition: lost potential strength and reduced vessel use-life. Overall, untempered samples were significantly stronger than samples tempered with the most commonly used regional tempers—grit, limestone, and burnt shell—in terms of peak load and modulus of rupture. In other words, the results presented here suggest that prehistoric potters were losing the opportunity to create significantly stronger vessels in favor of the benefits that come with the addition of temper. Understanding of the existence, kind, and degree of opportunity costs that come with the addition of temper to clay emphasizes just how important the benefits of tempering must have been for the technology to be invented, experimented with, and ultimately so widely adopted.

Publication date: September 2017Source:Journal of Archaeological Science, Volume 85

Publication date: Available online 15 August 2017Source:Journal of Archaeological Science Author(s): Miljana Radivojević, Thilo Rehren, Shahina Farid, Ernst Pernicka, Duygu CamurcuoğluThe scholarly quest for the origins of metallurgy has focused on a broad region from the Balkans to Central Asia, with different scholars advocating a single origin and multiple origins, respectively. One particular find has been controversially discussed as the potentially earliest known example of copper smelting in western Eurasia, a copper ‘slag’ piece from the Late Neolithic to Chalcolithic site of Catal-hoyuk in central Turkey. Here we present a new assessment of metal making at Çatalhöyük based on the re-analysis of minerals, mineral artefacts and high-temperature materials excavated in the 1960s by J. Mellaart and first analysed by Neuninger, Pittioni and Siegl in 1964. This paper focuses on copper-based minerals, the alleged piece of metallurgical slag, and copper metal beads, and their contextual relationship to each other. It is based on new microstructural, compositional and isotopic analyses, and a careful re-examination of the fieldwork documentation and analytical data related to the c. 8500 years old high-temperature debris at Çatalhöyük. We re-interpret the sample identified earlier as metallurgical slag as incidentally fired green pigment, which was originally deposited in a burial and later affected by a destructive fire that also charred the bones of the interred body. We also re-confirm the contemporary metal beads as made from native metal. Our results provide a new and conclusive explanation of the previously contentious find, and reposition Çatalhöyük in a new narrative of the multiple origins of metallurgy in the Old World.

Publication date: Available online 7 August 2017Source:Journal of Archaeological Science Author(s): Ernst PernickaIt is argued that it is unlikely that iridium can be used as tracer for the provenance of ancient silver for geochemical reasons. Instead it is suggested that the observed low but measurable iridium concentrations may be due to silver produced from argentiferous gold by cementation. It is furthermore argued that the calculation of geological model ages from lead isotope ratios does not provide any additional information compared with the use of conventional three-isotope diagrams.

Publication date: Available online 5 August 2017Source:Journal of Archaeological Science Author(s): Jonathan R. Wood, Michael F. Charlton, Mercedes Murillo-Barroso, Marcos Martinón-TorresWe present a detailed response to Professor Pernicka’s critique of our paper entitled “Iridium to provenance ancient silver”. We have concluded that Pernicka’s hypothesis, which suggests that elevated levels of iridium in ancient silver artefacts is a consequence of silver deriving from the cementation (parting) process, does not account for the available evidence and that his critiques of the analyses we presented seem misplaced. We offer a simpler solution and show that the structure of our transformed data is founded on logical reasoning which is borne out by the empirical results. Essentially, this response supports our view reported in the original paper that the variation in iridium in ancient silver is largely geological rather than a consequence of de-silvering gold.

Publication date: August 2017Source:Journal of Archaeological Science, Volume 84

Publication date: September 2017Source:Journal of Archaeological Science, Volume 85 Author(s): Stephen R. Merritt, Kellyn M. DavisZooarchaeological assemblages in a variety of geographic and temporal contexts are dominated by fragmentary long bone specimens, and precise identification of side, skeletal element, and bone portion underlie archaeological interpretations, including specimen counts for skeletal part profiles, minimum number of element (MNE), and individual (MNI) estimates. Actualistic hammerstone and anvil breakage of domestic goat limb bones was used to document how fragmentation impacts precise identification of skeletal specimens, analysis of assemblage composition, and reconstructions of butchery behavior. Specimens greater than 2-cm in size were assigned to categories that describe the precision with which side, element, upper, intermediate and lower limb segment, and long bone portion could be identified. Results suggest that specimen size is positively related to identifiability, and more identifiable specimens tend to include epiphyses and relatively complete shaft circumferences. Most elements produced a similar number of fragments, including highly identifiable ends that yield accurate skeletal part profiles, MNE, and MNI estimates. However, if density-mediated destruction removes these specimens, analysis of less-identifiable shaft fragments significantly underrepresents element and individual abundance. The number of identified limb specimens (NISP), MNE, and epiphysis-to-shaft ratios in fragmentary archaeological butchery assemblages suggest limb end underrepresentation deflates measures of assemblage abundance and reduces the behavioral resolution of butchery interpretations. However, zooarchaeological analyses can productively incorporate fragmentary, less-identifiable specimens when they define hypotheses that match the scale of archaeological data.

Publication date: September 2017Source:Journal of Archaeological Science, Volume 85 Author(s): Jessica C. Thompson, J. Tyler Faith, Naomi Cleghorn, Jamie HodgkinsTaphonomic analysis is an essential component of zooarchaeology, but is employed in different ways within different research traditions. Within the Africanist Palaeolithic literature, there is a strong emphasis on quantitative comparison of proportions of different bone surface modifications to one another and to proportions observed on modern experimental collections. This work has been driven by debates about the taphonomic histories of Oldowan sites that document the subsistence strategies of early Homo, but this specific approach can be usefully applied to a range of contexts across many different time periods and geographic locations. One obstacle to the cross-fertilization of this taphonomic tradition with other zooarchaeological work is the restrictive manner in which data are selected from an assemblage for analysis. To ensure comparability between fossil and modern assemblages, analysts typically exclude specimens with evidence for post-depositional modification not modeled in the experimental data. Although this adds interpretive robustness, it can diminish sample size significantly, sometimes to the point of affecting statistical analyses, and results in much time invested in collecting data that ultimately are not used. Here, we describe a new method for maximizing the number of specimens that can be incorporated into analysis, thus resolving the persistent problem of poor sample sizes to make more statistically robust comparisons to actualistic datasets.