Abstract: Simple flake cutting tools were utilized across broad chronological and geographical ranges during prehistory. Fundamental to their functional utility is the presence of a relatively acute working edge. The acuteness of this ‘edge angle’ is widely hypothesized to be a primary determinant of cutting efficiency and, subsequently, of potential consequence to prehistoric peoples. However, the influence of the cutting edge angle in flake tools on the ability (efficiency) of tool users to cut through objects has not been empirically investigated under explicitly stated experimental conditions. Moreover, no consideration has been given to whether this relationship is dependent upon the size of the tool. Here, the influence that edge angle exerts on human stone tool users is examined experimentally in terms of efficiency during a cutting task, while also considering the relationship between edge angle, loading (i.e., the force applied) and overall flake size. The results demonstrate that there is a highly significant relationship between more acute working edges and increased cutting efficiency in the smallest flake tools tested. Above a certain flake-size threshold, however, the working edge angle has no influence on cutting efficiency because larger flakes appear to facilitate the application of greater working loads by tool users. These results have important implications for potential flake selection criteria by prehistoric peoples, especially in relation to utility, function and the changing effects of edge angle through a sequence of retouch.

Abstract: A database of the ancient marbles of Goktepe near Aphrodisias is reported, and includes 160 white, black and bichrome samples from 13 quarries and two waste deposits. The quarries are grouped into four districts. Districts 1 and 2, to the north, produced exclusively black or dark grey marbles (nero antico). Districts 3 and 4 produced white statuary marble. Nero antico and a black and white stone were also quarried in district 4, where the black marble surfaces again. The samples were characterized using petrography, isotopic analysis, EPR spectroscopy and trace analysis. The Goktepe white exhibits an unparalleled combination of fine grain, low EPR intensity and high strontium concentration that often allows easy identification. The isotopic values are less distinctive and similar to those for Carrara. In most cases, however, they are tightly grouped and also quite indicative. The black marbles exhibit a much weaker metamorphic overprint. With respect to the white marbles, they show analytical similarities but also notable differences. Therefore, establishing their provenance can be more difficult and may require the support of petrographic analysis. The results suggest that the Goktepe marbles were among the most prized and widespread statuary marbles used in Roman times, particularly from the early second century ad onwards.

Abstract: This paper introduces a new set of certified reference materials designed to aid scientists and conservators working in cultural heritage fields with quantitative X-ray fluorescence analysis of historical and prehistoric copper alloys. This set has been designated as the Copper CHARM Set (Cultural Heritage Alloy Reference Material Set). The Copper CHARM Set is designed to be used by a wide range of museum-, art- and archaeology-oriented scientists and conservators to help improve the accuracy and range of their calibrations for quantitative ED–XRF spectrometry of copper alloys, and also increase the number of elements that can routinely be quantified. In addition, the common use of a single core set of the reference materials is designed to significantly improve inter-laboratory reproducibility, allowing greater data sharing between researchers and thus furthering possibilities for collaborative study.

Abstract: We present a new methodology for interpreting lead isotope data from archaeological copper alloy objects. It is not based on the conventional isotope ratio biplots, which were originally devised to allow the calculation of the geological age of the lead mineralization, but is derived from isotope mixing models, more often used for presenting strontium isotope data. We illustrate the method by reworking published data on Sardinian Nuragic oxhide ingots and copper alloy artefacts. While we confirm the consensus assumption that the oxhide ingot fragments found on Sardinia are isotopically consistent with Cypriot copper ores (although we see no isotopic reason to favour only Apliki, as originally suggested), we also show that there is evidence for mixing between local and ingot copper in some objects, which was previously not detected. More broadly, we suspect that the apparent mismatch between some source allocations for copper drawn from isotope geochemistry and the rest of the archaeological data in some cases might be due to mixed isotopic signals being incorrectly assigned to a specific source, and suggest that the method presented here will reduce the chances of this happening.

Abstract: A range of archaeological and palaeoclimatic studies use isotopic analyses of ungulate hypsodont tooth enamel. Such studies commonly assume a constant growth rate, though this has not been fully tested. Here, we use stable isotope analyses of sequential enamel samples to study horse tooth growth. We fit the data using models corresponding to constant and exponentially decreasing rates of growth, and compare the results to metrical data showing the geometry and timing of apposition. The results indicate enamel apposition and maturation advances at an exponentially decreasing rate. An understanding of this variable growth rate is crucial for interpreting isotopic data from equid teeth.

Abstract: Twenty-six samples from domestic assemblages of 9th–12th century Cordoba were subjected to electron microprobe analysis The results reveal two main compositional types The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high-impurity sand, and has some contemporary parallels from Syria and Egypt The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world

Abstract: This contribution focuses on the study of historical mortars from a Roman archaeological site known as Villa dei Quintili, a monumental villa located in the south-eastern part of Rome (Italy). The study was carried out on 38 mortar samples, collected from several edifices within the complex. A multi-analytical approach, including polarized optical microscopy, scanning electron microscopy coupled with energy-dispersive system and laser ablation inductively coupled plasma mass spectrometry, was used to analyse the pozzolanic material used for the preparation of mortars. Data obtained on both major and trace elements were compared with the compositions of Pozzolana Rossa, Pozzolana Nera and Pozzolanella samples from the Alban Hills volcanic district, collected from a historic quarry nearby, as well as with literature data. The results of such a multidisciplinary approach allowed us to recognize the use of all three pozzolan types for the aggregate fraction of examined mortars from the Villa dei Quintili.

Abstract: Colour plays an eminent role in beadwork. Colour modifications are reported on early shell beads from Middle Stone Age sites. However, identifying the colouring agent and demonstrating the intentional nature of the colouring process is not straightforward. Here, we provide analytical data on colour and structural modifications observed on Nassarius kraussianus (Nk) collected in modern thanatocoenoses and on shells of the same species experimentally heated in oxidizing and reductive atmospheres. Comparison with Nk shell beads from the 72 ka old Middle Stone Age levels of Blombos Cave, South Africa, and contextual analysis of other malacological remains from the same levels that were not used as ornaments identify the mechanisms responsible for the change of colour in modern Nk thanatocoenoses and heated shells, and show that although some Nk shell beads were heated, intentional heat treatment of shell beads is not demonstrated.

Abstract: Distinctive mulberry paintings found in northern Australia, particularly those of the Kimberley region, have been argued to represent some of the oldest surviving rock art on the continent. Significant research efforts continue to focus on resolving the age of these motifs, but comparatively little attention has been given to understanding their physical composition and potential source(s). In a pilot investigation, we conclude that (at least) two mineralogically distinct mulberry pigments occur in Gwion motifs and demonstrate that their major components can be indicatively chemically differentiated, non-invasively. Characterization of a ‘quarried’ mulberry ochre source demonstrates that these pigments occur locally as natural minerals.

Abstract: This paper reports the results of an archaeometric study of the crystalline marbles used in the Roman city of Banasa (Morocco). On-site surveys allowed a detailed inspection of the monuments of the ancient city and sampling of the different marble lithotypes used for architectural purposes and sculptures. The inventory was completed by the study of both the grey-and-white streaked or spotted marble items stored in the warehouse of the archaeological site and of those currently exhibited at the National Archaeological Museum of Rabat. Provenance determination of 28 samples was carried out by means of a multi-method approach combining mineralogical–petrographic data and C–O stable isotope analyses as the first step, and cathodoluminescence microscopy as a complementary technique to verify possible unusual alternative origins of some marbles. The analytical results obtained were compared with both the most reliable international databases and the few available studies dealing with the use of marble in other Roman towns in Morocco (e.g., Volubilis, Thamusida and Sala-Chellah). They point to a variety of classical marble sources such as Carrara, Mount Penteli, Paros, Marmara and probably Mount Filfila (Algeria), and prove a significant import of Iberian lithotypes.

Abstract: A group of the late 12th–13th century Byzantine pottery glazes, mostly related to Zeuxippus Ware Type pottery from the Kusadasi Kadikalesi/Anaia site in western Anatolia, was characterized non-destructively using Raman spectrometry. SEM–EDX was also used complementarily for the glaze characterization. The nature and composition of the glazes, firing conditions, aspects of colour formation and pigments used were discussed. The glazes were found to be lead-rich silicates, fired close to 700°C on the basis of the Si–O stretching peak maxima of the Raman spectra recorded at ∼920–980 cm–1, as also confirmed by SEM–EDX analysis. The polymerization index values calculated are between approximately 0.05 and 0.1. The use of biscuit-fired bodies prior to glaze application was suggested based on the results of SEM–EDX analysis. In particular, the detection of Naples yellow pigment variations on a locally produced pottery sample is quite significant, since the use of this type of pigment has hardly ever been reported between the Roman period and the Renaissance.

Abstract: The sensitivity of organic-rich archaeological layers at Bryggen in Bergen, Norway, to changes in soil temperatures, water contents and oxygen concentrations is investigated. This is done by linking measurements of oxic decay at varying temperatures and water contents with on-site monitoring data using a one-pool decomposition model. The results show that the model can be used to elucidate the current in situ decay and to evaluate where and when the decay takes place. Future investigations need to include long-term incubation experiments and decay studies at zero or very low oxygen contents in order to improve the robustness of predictions.

Abstract: Long-distance networks for the transport of exotic goods and the beginnings of specialized craft production first appear in Mesoamerica during the Formative Period. The results of portable X-ray fluorescence (pXRF) analysis of 456 obsidian artefacts imported to the Pacific coast site of La Zanja (Guerrero, Mexico) indicate that long-distance exchange of finished obsidian blades along the coast began during the Early Formative (c.1400–1000 cal bc) and remained constant into the Middle Formative Period (c.800–550 cal bc). Comparisons with sourcing studies from elsewhere in Mesoamerica indicate the development of a major Pacific coast trade network during the Formative Period that linked coastal Guerrero to the central Mexican highlands and the Valley of Oaxaca. Weaker connections existed with Gulf coast obsidian trade networks that traversed the Isthmus of Tehuantepec. As the first obsidian sourcing study from coastal Guerrero, these data contribute to a greater understanding of the development of exchange networks in Mesoamerica during the Formative Period.

Abstract: In this study, we compared the effectiveness of instrumental neutron activation analysis (INAA) of bulk ochre to laser ablation-inductively coupled plasma mass spectrometry of homogenized ochre chips (HOC LA–ICPMS) at distinguishing among three ochre sources in northern Malawi. Both techniques upheld the Provenance Postulate; however, HOC LA–ICPMS required less sample material than INAA and facilitated fast, inexpensive replicate observations that allowed for more robust statistical analysis. Our results indicated that HOC LA–ICPMS is a maturing technique that will be a valuable option for analysing artefacts that require minimally destructive sampling but are too large to fit into the laser cell for direct ablation. With regard to the statistical procedures used, stepwise canonical discriminant analysis was demonstrated to be a highly effective method for distinguishing among ochre sources, even in the presence of significant intra-source and intra-sample heterogeneity. Continued development of the HOC sample preparation technique will expand the range of archaeological ochre artefacts that can be included in provenance studies and prevent bias towards artefacts of convenient-to-analyse dimensions.

Abstract: In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west facade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan’s Sacred Precinct comes from the Tula region.

Abstract: From the Neolithic up to the present, people have used various methods to improve the surface of ceramic objects. In this study, we look specifically at smoothing and pattern burnishing of ceramics produced today by traditional methods. Optical microscopy and SEM show specific surface changes. Smoothing results in an irregular surface, which causes diffused reflection of light. Burnishing produces an even and compact surface, which causes specular reflection and lustre. The results can be used to infer methods of surface treatment employed by ancient peoples as well as to help identify the presence of ceramics production centres at archaeological sites.

Abstract: Through a combination of analysis and synthesis of Laohudong Guan ware shards from Hangzhou City in southern China, some new hypotheses concerning Guan ware manufacture can be proposed. These suggest that the complex microstructures seen in Guan ware glazes, and which contribute significantly to their jade-like qualities, may owe much to layers of fine bubbles trapped during the glazing process. It is also proposed that the multi-layer glazing methods used at the Guan ware kilns at Hangzhou may have helped initially to disguise the relatively coarse and ferruginous clays used for Guan ware manufacture. Once established, the layered glazing technique was used for its own sake—eventually yielding wares that could comprise more glaze than clay. Raw materials and firing temperatures were also explored for this study, and these suggest the use of porcelain-stone/wood ash mixtures for glaze-making, with 20–30% calcareous wood ash being the usual amounts. The average heat-work for the glaze firing seems to have been equivalent to Orton Cone 7, giving a typical finishing temperature of ∼1215°C. A single biscuit firing and a single glaze firing seem likely for most Laohudong Guan wares. Studies of the losses that occur in the preparation of calcareous wood ashes suggest that very large quantities of botanic material must have been burned to provide ash for glaze-making at the Laohudong kiln. From the environmental perspective, a combination of thick glazes and heavy wood-ash usage would have placed great demands on local fuel supplies.

Abstract: Fil: de la Fuente, Guillermo Adrian Universidad Nacional de Catamarca Escuela de Arqueologia; Argentina Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

Abstract: The Morgantina archaeological area, inhabited from the Early Bronze Age, had its widest expansion from the fifth to the first century bc. The volcanic millstones found at Morgantina fall into three different groups on the basis of the milling technique: (i) saddle querns (known from the Middle–Late Bronze Age and Iron Age); (ii) rectangular hopper-rubbers (Olynthian) millstones, the invention of which dates to the fifth century bc; and finally (iii) Morgantina-type rotary millstones (starting to be used from the fourth to the third century bc). In order to determine the provenance of the raw materials (lavas) used for all these millstone types, we collected 38 very small rock samples for thin-section modal mineralogy, petrography and major trace element composition. The results have contributed to classifying different lithotypes and distinguishing between provenance from Etna and the Hyblean Mountains, the two volcanic areas respectively north-east and south-east of Morgantina. Saddle querns are made of tholeiitic basaltic andesites from the Hyblean Mountains and transitional basalts, mugearites and hawaiites from Etna. The variety of sources of portable saddle querns, mostly used in households, indicate that there was no general preference for specific quarrying sites. By contrast, the rectangular hopper-rubber and the Morgantina-type millstones, which document the period of Morgantina's greatest prosperity, are almost completely made of hawaiites from Etna. The use of a specific lithotype (i.e., Etna hawaiite) for the more efficient rectangular hopper-rubber and rotary millstones could be linked to the fact that these mills may have been operated in business establishments. It is worth noting that the Gornalunga river was, in antiquity, a waterway joining Morgantina to the final stretch of the Simeto river and then the Ionian coast. The best candidate areas for the millstone hawaiite quarrying sites from Etna are the far south-western sectors of the volcano, along the Simeto Valley (i.e., the ‘Piano Provenzana’ Formation) or the inner suburb of present-day Catania (i.e., the ‘Pietracannone’ Formation). The very efficient Morgantina-type rotary millstones spread during the reign of Hieron II of Syracuse (275–215 bc) in eastern Sicily and met the need for grinding large quantities of cereals during a relatively peaceful time and a period of agricultural development.

Abstract: The characterization of sedimentary particles and minerals present in the charcoal and woody archaeological remains contributes to determining the different sedimentary, archaeological and taphonomic processes that affected them. In order to prove this assumption, woody remains at the Orejas de Burro 1 archaeological site (Argentina) were studied, and a pilot programme was undertaken to study the chemical composition of the wood and the causes of its variation. Wood samples from the same plant species found at the site, Nothofagus pumilio and Berberis sp., were collected from different forest, coastal marine and lake areas in Patagonia, charred, analysed and compared to archaeological samples. Modern reference charcoal samples show mainly the elements, C, O and probably Ca and K, involved in the organic plant tissues, whereas the presence of additional chemical elements (Al, Si, Fe, Na, Mg, K, Cl and Ca) and/or minerals in modern and archaeological charcoal and wood samples suggests that they have been in contact with seawater, pointing to the use of driftwood and the occurrence of different taphonomic processes. The results obtained allow us to propose that in the past driftwood was collected as firewood along the coast of the Strait of Magellan, and to highlight the potential of the geochemical and mineralogical studies in archaeobotanical materials.

Abstract: We studied the composition, colour chromaticity and form of application of red pigments in human bone samples from seven Classic period Lowland Maya sites. The samples were analysed by X-ray diffraction, scanning electron microscopy (SEM) and X-ray energy-dispersive spectroscopy (EDS). Colour was measured using conventional colour identification standards (Munsell) and reflectance spectroscopy. Cinnabar and hematite were identified as the pigments used. We conclude that the reflectance method has advantages over conventional visual results, as it provides precise, objective and quantifiable optical data to distinguish the chromaticity, colour saturation and brightness of the pigments.

Abstract: At the hill of Agios Symeon, on the island of Kea, Aegean Sea, Greece, ancient metallurgical slags with a high Pb–Zn–Cu content have been found. Thermodynamic simulations have been carried out, using the FactSage™ thermodynamic database computing system, with a view to understanding the ancient metallurgical processes that produced the observed slag compositions and morphologies. The simulations demonstrate that the slag samples resulted from Cu-making processes. It would thus appear that mixed ores were used, containing Cu2S–FeS–PbS with significant amounts of sphalerite (ZnS) as impurity. The roasted ores were reduced at relatively high oxygen potentials at ∼1125°C to form Cu containing low levels of Pb, Fe and Zn.

Abstract: The petrography as well as the major and trace element compositions of the Selinunte grinding stones, made of grey vesicular lava, were analysed. By comparison with geochemical data from volcanic rocks in the Mediterranean, we were able to determine that only a minor number of the tools were extracted from the nearest volcanics of Mount Etna and the Hyblean Mountains, while the majority of the grinding stones were most probably imported from the Aeolian Islands, although an origin from the Aegean cannot be excluded entirely. The results are important in order to scrutinize trading connections, especially for the earlier times of settlement during the sixth century bc.

Abstract: The rehydroxylation (RHX) dating method applicable to virtually all baked clay fragments still requires testing and new developments. Here, we have obtained new weighing measurements from Syrian medieval ceramic fragments. In particular, they allow us to illustrate the scatter in RHX behaviour that may exist between different potsherds of the same age and found at the same archaeological site, thus having experienced the same effective lifetime temperature, and even between samples collected from the same artefact. Thanks to a so-called time-span analysis, we also report on some complexities in data sets previously obtained by Wilson et al. (2009, 2012, 2014).

Abstract: Ceramic ethnoarchaeology has been used to explore fully the chaine operatoire and to understand all of the stages and factors involved in pottery production, such as raw material selection or paste recipes used by the potters. This work presents the results of the application of compositional analysis undertaken in the village of Pabillonis (western Sardinia, Italy), the main cooking ware production centre of the island. Pottery and local clays have been characterized using a combination of analytical techniques. By integrating the ethnographic information and the archaeometric approach, it was possible to reconstruct the operational sequence, exploring the relationship between the processing of raw materials and the functionality of the final products, and the intra-production compositional variability.

Abstract: Underwater surveys along the Israeli Carmel coast have revealed six cargoes of iron semi-products associated with shipwrecks. They are described and dated according to the associated artefacts. Metallographic and chemical analyses on samples from the biggest cargo have determined the stages of the chaine operatoire, identified the properties of the iron and characterized the iron trade along the Israeli coast. The new discoveries contribute to our understanding of the circulation of iron in the South Levant, which was characterized by an almost complete absence of local iron production. During the Byzantine and Crusader periods, this absence was compensated by long-distance sea trade, depending on political circumstances and restrictions. Three main types of iron semi-products were identified: (a) partly consolidated blooms, (b) short pointed bars and (c) elongated pointed bars. The cargoes discovered represent a time period of nearly a millennium. Altogether, 148 iron semi-products were studied. Of these, 166 were from cargo a, which was dated by coins to around 1130–1200 ce. Those coins could have been imported from Europe for Crusader military and civil uses in the Levant. The iron from cargoes b, d and f, dated perhaps to the Byzantine period, could have been imported from Anatolia or Venice for military and civil purposes.

Abstract: This is the 35th list of AMS radiocarbon determinations measured at the Oxford Radiocarbon Accelerator Unit (ORAU). Amongst some of the sites included here are the latest series of determinations from the key sites of Abydos, El Miron, Ban Chiang, Grotte de Pigeons (Taforalt), Alepotrypa and Oberkassel, as well as others dating to the Palaeolithic, Mesolithic and later periods. Comments on the significance of the results are provided by the submitters of the material.

Abstract: In rehydroxylation (RHX) dating, the activation energy of the rehydroxylation reaction is required first in the estimate of a material's effective lifetime temperature (ELT), and second to correct the RHX rate constant obtained at a given measurement temperature to that at the ELT. Measurement of the activation energy is thus integral to the RHX methodology. In this paper, we report a temperature-step method for the measurement of activation energy and develop fully the underlying theoretical basis. In contrast to obtaining the activation energy from a series of separate experiments (each of which requires the sample to be dehydroxylated prior to measuring the RHX rate constant), the temperature-step method not only requires a single dehydroxylation at 500°C but also eliminates repeated acquisition of Stage I data, which are not required for dating purposes. Since the first temperature step is set to correspond to the temperature at which a dating determination is carried out, the measurement of rate constants at higher temperatures simply becomes an extension of dating. Consequently, the logistics of obtaining the activation energy of rehydroxylation are greatly simplified.

Abstract: Pattern-welding is a well-known technique that was widely employed in the manufacture of swords. While the decorative effect of genuine pattern-welding (employing phosphoric iron) is indisputable, to date its reinforcing effect is rather unclear. In order to understand this issue better, wrought iron, phosphoric iron, steel and various pattern-welded samples were prepared and mechanically tested, and the results obtained are discussed in detail. Both the mechanical testing and the long-term metallographic investigation of medieval swords suggest that pattern-welding does not have any significant positive effect on the mechanical properties of swords and we should consider it a primarily decorative technique.