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Geopolymer mortars, which cause less CO2 emissions than concrete and its raw material cement, are an innovative, environmentally friendly and sustainable building material. Geopolymers are formed by activating silica and alumina materials with alkaline activators. In this study, a geopolymer mortar containing obsidian (OB), also known as volcanic glass, which is free, and silica fume (SF), which is the waste material of the silicon and ferrosilicon industry, was investigated. The behavior of OB‐based geopolymer mortars under different curing times ranging from 2 to 120 h and different thermal treatment temperatures such as 90, 150, and 200°C were examined. The effectiveness of OB and SF on the physical features, compressive strength (CS), and micro‐structural of the geopolymers were characterized. Results demonstrated that the peak CSs were acquired in 96 h at 90 and 150°C heat treatment temperatures, while the highest CSs were acquired in 72 h for specimens subjected to 200°C heat treatment. Reduces in CSs were detected when the curing time exceeded the ideal limit. OB‐based geopolymer was found to be stable with SF and there was a linear relationship between SF substitution ratio and CS. The density of the mortar pieces decreased with increasing thermal curing hours. Devolving on the thermal temperature and curing time, the microstructures became more compact and microvoids and cracks decreased. It was observed that SF substitution reduced the total pore size of the geopolymers and allowed the pore structure size to be reduced. The results obtained from the study are expected to encourage the utilize of industrial wastes and new binders in the manufacture of geopolymers. [ABSTRACT FROM AUTHOR]

We examine provenance data collected from three types of geological resources recovered at Goat Spring Pueblo in central New Mexico. Our goal is to move beyond simply documenting patterns in compositional data; rather, we develop a narrative that explores how people's knowledge and preferences resulted in culturally and materially determined choices as revealed in those patterns. Our analyses provide evidence that residents of Goat Spring Pueblo did not rely primarily on local geological sources for the creation of their glaze paints or obsidian tools. They did, however, utilize a locally available blue-green mineral for creation of their ornaments. We argue that village artisans structured their use of raw materials at least in part according to multiple craft-specific and community-centered ethnomineralogies that likely constituted the sources of these materials as historically or cosmologically meaningful places through their persistent use. Consequently, the surviving material culture at Goat Spring Pueblo reflects day-to-day beliefs, practices, and social relationships that connected this village to a broader mosaic of interconnected Ancestral Pueblo taskscapes and knowledgescapes. [ABSTRACT FROM AUTHOR]

The Salado and Verde streams constitute the two main seasonally available freshwater courses that flow into the Atlantic coast of the Río Negro province (continental Patagonia, Argentina, 42° South). This would have favored their use in the past as corridors for human circulation between the coast and the interior. This paper presents the results of the technomorphological and geochemical analyses of the obsidian artifacts recovered in the area to constrain mobility. The results allow us to propose the existence of toolkit reconditioning or replacement activities, and the identification of different sources of provenance of the obsidians (Sacanana, Telsen, and Portada Covunco, distant up to 800 km from the study area), reinforcing the hypothesis of a coast–inland circulation, with the possible existence of circuits of exchange of this raw material. [ABSTRACT FROM AUTHOR]

One way to improve the mechanical properties of composite structures is by hybridizing natural and synthetic fibers. Besides that, combined with sandwich structure composites consists of two relatively strong, thin, and stiff faces separated by a core, for example, balsa, foam, and honeycomb, a relatively thick lightweight. This research develops sandwich composites for structures that have able to withstand high loads and modulus-to-weight ratios but can absorb impacts through impact tests by utilizing the raw material of jute natural fiber, which is abundant in Indonesia so that this research study can predict the effect of variations in the hybridization of hemp natural fiber and the combination of hemp natural fiber with e-glass using polypropylene core sandwich composites by using hand lay-up and vacuum bagging methods. The current impact test results show that the hemp natural-e-glass fibers hybrid sandwich composites get a higher impact strength with a value of 0,019 J/mm² than the hemp-PP honeycomb hybrid sandwich composite with a value of 0,013 J/mm². It shows that by combining e-glass fiber in the composite, it can increase its impact strength and can be a lightweight structural material as being a new alternative material of jute and e-glass natural fiber hybrid sandwich composites with polypropylene cores to substitute conventional materials such as metals which is potential for applications in the automotive, building, and unmanned aerial vehicle industries. [ABSTRACT FROM AUTHOR]

Copyright of Študijné Zvesti AU SAV is the property of Institute of Archaeology SAS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios Atacameños is the property of Estudios Atacamenos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Intersecciones en Antropología is the property of Universidad Nacional del Centro de la Provincia de Buenos Aires, Facultad de Ciencias Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The authors studied 36 obsidian-tipped spears in the Oceania collection of the Museum of Ethnography in Budapest. In addition to describing the objects from the Admiralty Islands collected before 1897, the paper provides a summary of the related ethnographic information, including the technological and technical details of spear point making and the characterisation of the obsidian raw material used. The blades used for making the obsidian points presented in this study showed no sign of standardisation (an indicator of advanced blade technology) in the spear point-making process. According to 19th-century ethnographic sources, the functional part of the points was the most important, and much time and effort were invested in ensuring that the blades were effective weapons. Later, as a sign of decline, primary production of obsidian blades ceased, and manufacturers started scavenging old artefacts and utilising waste and by-products. As a result, the blades decreased in size and became more irregular, and an increasingly large number included parts of the cortex, the crust of obsidian. After 1911, the relative importance of decoration increased, and the type became more standardised. The irregular shape of the spear points presented in the study and the thin, weak shafts with an awkward curvature raise questions about whether the spears were actual weapons. At the same time, the artistic decoration of the mounting sockets and ethnographic parallels suggest that the pieces in the collection were likely status objects instead. [ABSTRACT FROM AUTHOR]

Stone‐tipped weaponry was important for the survival of past peoples, and many functional and non‐functional factors likely influenced their design. Two functional factors that past peoples likely considered in the design of their stone tips are durability (whether or not a stone tip breaks) and robusticity (how much damage is incurred upon breakage). Many factors have been shown experimentally to influence stone tip influence durability and robusticity, including stone raw material. Here, we further explore the relationship between stone raw material and stone tip durability and robusticity via controlled experiments comparing chert and obsidian. We first demonstrate with semi‐static fracture strength analyses that obsidian stone tips require less force to break than do chert stone tips. We then show with dynamic ballistics impact testing that obsidian stone tips are less durable and robust than chert stone tips. Our results are entirely consistent with previous experimental comparisons of chert versus obsidian stone tips, and support the hypothesis that past peoples, when presented with multiple raw materials, likely weighed their costs and benefits in the process of selection. [ABSTRACT FROM AUTHOR]

This paper takes a practice-based approach to the study of cultural identity, focusing on how raw material and technical choices involved in the production of quotidian tools served to both reproduce, and reflect a social group's very way of being. We then consider the (dis)continuity of obsidian blade-making traditions from Middle–Late Bronze Age Malia (north-central Crete), i.e., before and after a period of island-wide destructions, and appearance of foreign elements believed to reflect the arrival of a population from the Greek mainland (Mycenaeans). Methodologically this involves an integrated, 'thick description' obsidian characterisation study to detail long-term cultural traditions, including the use of Neutron Activation Analysis (NAA) to source the raw materials of 36 artifacts. The results show a significant degree of continuity in the community's lithic traditions, suggesting that many of the innovative features at Malia can be interpreted in terms of local factions appropriating new and foreign means of social distinction, rather than wholescale changes in community composition. [ABSTRACT FROM AUTHOR]

Both obsidian and perlite belong to acid volcanic rock and have a similar structure and chemical composition, but the insulation material prepared from expanded obsidian cannot reach the performance level of that prepared from expanded perlite. To date, obsidian cannot be used in large quantities, although its resource is abundant. In order to comprehensively utilise this resource, in the present work the authors developed a new type of lightweight thermal insulation material by using obsidian as a main raw material which is energy-efficient and environmentally friendly. The effects of raw materials such as obsidian, sodium silicate, hydrogen peroxide and cetyltrimethylammonium bromide on physical properties including thermal conductivity, porosity, density and compressive strength were studied in detail. The optimised thermal insulation material exhibits low thermal conductivity (0.051–0.86 W m−1 K−1), low density (0.1–0.24 g/cm3) and adjustable compressive strength (0.09–1.52 MPa). Compared to other inorganic insulation materials, this new thermal insulation material is very light and has a better thermal insulation performance. Therefore, this work proposes a new energy-efficient way to prepare a promising noncombustible thermal insulation material, and also provides a way to use obsidian resources in large quantities. [ABSTRACT FROM AUTHOR]

Perlite is an amorphous volcanic glass and an industrial mineral. Because of its relatively low price and density, perlite has a lot of commercial application. Generally, it is used in the horticultural and construction sector. Perlite is a candidate raw material for ceramic products due to its high amorphous phase. Perlite usage in ceramic sanitaryware is investigated with this work. For this purpose, albite was gradually decreased and perlite was added at rates of 3, 5, and 10% to the standard sanitaryware composition instead of albite. All tests and analyses were done under industrial conditions. The compositions were examined based on the rheological and technological properties, chemical analysis, phase analysis, and thermal analysis (thermal expansion coefficient and high-temperature deformation). According to the results, perlite addition increases fired shrinkage, fired strength, and dry shrinkage. Fired strength rose significantly up to 715 kg cm−2. Water absorption values were under 0.02% for all test samples. Besides, the thermal expansion coefficient of the bodies increased up to 10% with perlite addition and then decreased. Thermal expansion coefficient values were determined between 60.1 and 64.9 × 10−7 K−1. High-temperature deformation values decreased up to 10% with perlite addition. The composition which contains 3% perlite showed minimum deformation (− 4.25%) at 1250 °C. As a result, it was determined that the use of perlite would be possible in ceramic sanitaryware compositions. [ABSTRACT FROM AUTHOR]

Kendale Hecala is located on the Ambar River in the Upper Tigris Basin, province of Diyarbakır in Southeast Anatolia. Various raw materials, including obsidian, radiolarite, chert, jasper, chalcedony, and quartzite, were used in the lithic industry. Obsidian artefacts constitute an average of 64% of the chipped stone assemblage. Technological analysis reveals that obsidian was brought to the settlement as nodules and chipped into various tools at the settlement. Understanding the operational sequence of the lithic industry, chaîne opératoire, including the distribution of raw material from source to site, is important to demonstrate the socio-cultural organization of the settlement in Southeastern Anatolia during the Ubaid period. In order to identify source varieties, the obsidian artefacts uncovered from Ubaid layers of Kendale Hecala were analyzed by macro-observations, and the characterization of archaeological samples was performed using a handheld XRF. Multivariate analysis of the data indicates the use of obsidian from different resources at the settlement, including Nemrut Dağ, Bingöl B, and Group 3d. [ABSTRACT FROM AUTHOR]

From the period of the Neanderthals to those of the Late Neolithic populations, the Bükk Mountains region played an important part in the lives of various prehistoric societies, and the varied geological history of this territory provided distinct circumstances for the production of stone implements. The major goal of our research is to outline the current state of information concerning the prehistoric use of the diverse silicified source materials of the Bükk mountains. The results of these studies are presented concerning four selected local rock types, cited in the archaeological literature as the silicified sandstone of Egerbakta, the radiolarite and hornstone (black chert), the silicified marlstone and the quartz-porphyry (metarhyolite). Except for the latter, little attention has previously been paid to studying them in detail. Our new petrographic analyses revealed two variants of the raw material from Egerbakta: a silicified sandstone and a diatomaceous detrital chert. The other samples turned out to be radiolarites. This result confirmed what was already suggested for the hornstones (black cherts), however, it has new consequences for the "silicified marlstone". Regarding the prehistoric use of the selected raw materials, archaeological data show interesting dynamics through time. The Mousterian groups of the region used a large spectrum of rocks for lithic tools with a preference for hornstone (black cherts) and radiolarite in the southern part, and the quartz-porphyry (metarhyolite) in the northeastern part. The Babonyian/Micoquian assemblages are characterized by a bifacial toolkit and an apparent preference for quartz-porphyry (metarhyolite). At the beginning of the Upper Palaeolithic, a new attitude appears in the region: the Aurignacian groups almost completely ignored local sources. During the Neolithization of the Carpathian Basin, the lithic assemblages of the Alföld Linear Pottery culture became more and more habituated to the locally available rock types, albeit their raw material economy was based on limnosilicites and obsidian. Another change took place during the Late Neolithic when supra-regional sources became dominant over local or regional sources. [ABSTRACT FROM AUTHOR]

Copyright of Mexicon is the property of Verlag Anton Saurwein and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recent archaeological research has highlighted the potential role of mobile pastoral groups in the diffusion of raw materials and technological innovations between the southern Caucasus and north‐western Iran from the Neolithic onwards. Two successive projects, PAST‐OBS and SCOPE, were designed to explore this hypothesis through the study of obsidian consumption patterns from the Neolithic to the Bronze Age using a flexible analytical strategy that considerably extends the scale of obsidian studies in these regions. By focusing on the exploitation of obsidian at multiple levels—local, regional and interregional—we hope to unravel the complexity of the obsidian networks under study. The aim of this paper is to present (1) a reassessment of the work so far carried out by previous obsidian studies, with a view to homogenizing and to clarifying the nomenclature in use; and (2) an introduction to the PAST‐OBS and SCOPE projects in order to initiate a discussion of our preliminary results. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mundo de Antes is the property of Revista Mundo de Antes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The region of Volcanic Cappadocia in Central Anatolia is home to the most important obsidian sources of Anatolia. As a knappable volcanic glass that could be transformed into sharp-edged tools, obsidian was intensively exploited as a raw material for tool technologies by the prehistoric communities. The rich obsidian sources in the region should have had influenced the location choices of the early sedentary communities. The circulation of the Central Anatolian obsidian throughout the Near East and Cyprus hints at a direct or indirect interregional network of communication from the early prehistory onwards. With the aim of documenting evidence on the interaction between communities and regions during prehistory, detecting the movement areas of communities, and locating new findspots, a survey was conducted on the northern slopes of the Niğde Massif that form the southeastern part of Volcanic Cappadocia. The Niğde Prehistoric Survey Project took place from 2016 to 2018. Following an introduction of the history of research in the region and a general overview of the geological and geographical characteristics of the Niğde Massif, this paper discusses the possible inter-regional interaction mechanisms based on the findspots detected during this survey project. [ABSTRACT FROM AUTHOR]

As a means of contributing to discussions on regional diversity in the earliest Neolithic lifeways of the Fertile Crescent (10th millennium cal BC), this article presents an EDXRF-based sourcing study of 332 obsidian artifacts from the hunter-fisher-gatherer village of Hasankeyf Höyük in southeastern Anatolia. While the techno-typological choices detailed conform largely to a pre-defined Upper Tigris cultural tradition, the distinctions in raw material selection reflect the "mosaic of exploitation strategies" that have come to typify the socio-economic practices of Early Holocene communities in the larger region (southwest Asia). Five obsidian sources are represented in the analyzed sample, with Nemrut Dağ products being dominant, plus smaller amounts of Bingöl A, Bingöl B, Muş and 'Group 3d' obsidian. The preference for Nemrut Dağ obsidian distinguishes this village from others of the Upper Tigris. By using a GIS-based least cost-path analysis, we suggest that community-specific traditions of raw material choice were part-influenced by these hunter-fisher-gatherers' use of rivers as their primary means of reaching the obsidian sources. The importance of the Tigris and its tributaries for transportation and cultural interaction is supported by various proxy data that lead us to argue that riverine movement and communication was an important aspect of Early Holocene lifeways in southwest Asia that has hitherto been largely ignored by archaeologists. [ABSTRACT FROM AUTHOR]

Copyright of Archaeological Materials & Research / Materiale şi Cercetǎri Arheologice is the property of Institute of Archaeology "Vasile Parvan" and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study uses data collected during three seasons of survey and excavation to examine evidence for the importation of obsidian and the production of tools, particularly blades, in the periphery of obsidian exchange spheres in the Nejapa/Tavela region of Oaxaca, Mexico. Sourcing information from X-Ray Fluorescence reveals a wide-ranging and shifting utilization of both Mexican and Guatemalan sources. Differences in the assemblages from contemporaneous sites hint at the social and political complexity of the region, which was inhabited by Zapotec, Mixe, and Chontal language speakers in multiethnic communities. Visible manufacturing errors and evidence of recovery techniques suggest that local artisans were capable producers of prismatic blades, demonstrating invaluable skills in a region where obsidian was scarce. The paucity of raw material and artisan skill is attested by relatively low frequencies of obsidian, as well as by deliberate manufacturing techniques designed to maximize the output of blades from each core. [ABSTRACT FROM AUTHOR]

Eastern Anatolia region of Turkey, where the owner has the geological structure as an important source of obsidian. One of the important obsidian source areas of the region is Bingöl obsidian beds. Obsidian beds within the geographical boundaries of Bingöl province are mostly located in the volcanic areas between Bingöl city centre and Solhan and Karlıova districts. Bingöl origin obsidians have been one of the important raw material sources traded in prehistoric times. That source of raw materials spread over large areas, mostly to the southern regions, as a result of commercial relations. However, field studies on these obsidian beds are limited despite the awareness of the obsidian beds in the provincial geography. For this purpose, in order to obtain more detailed data on obsidian beds in Bingöl, We initiated new archaeological studies in 2019. As a result of these studies, new obsidian sources were detected within the borders of Sarı Başak, Kulan and Efendi River hamlets of Yenihan Village of Solhan District, as well as Alatepe Village of Bingöl city centre. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study we used a multidisciplinary approach, coupling morphological, geological, geochemical, and statistical analyses to investigate the provenance of rhyodacitic and dacitic glass knapped at the Pilauco site (40°34′11" S, 73°06′17" W; 13,570 ± 70–12,540 ± 90 14C year BP) in northwestern Chilean Patagonia. A morphotechnological analysis was performed on the entire lithic assemblage, which is composed of cores, retouched and unretouched unifacial flakes, and small pieces of debitage, some of them closely associated with Notiomastodon aff. N. platensis gomphothere bones. Sixty‐two archeological and geological samples were analyzed by inductively coupled plasma mass spectrometry revealing a wide range of basaltic to rhyodacitic compositions. The archeological knappable dacitic and rhyodacitic glasses were recovered from pebbles deposited mainly on a beach away from the site, as deduced by the presence of minute and dense crescentic percussion marks on the cortexes. Geochemical trace element analysis suggests that the Puyehue–Cordón Caulle Volcanic Complex is the most likely source for the volcanic glass artifacts at Pilauco. The new morphotechnological and provenance record and improved stratigraphic sequences highlight the Pilauco site as an important contribution for the diversity of the South American geoarchaeological context. [ABSTRACT FROM AUTHOR]

Since at least 1742, the mineralogical collection of the Muséum National d'Histoire Naturelle (MNHN) in Paris has hosted, under the reference number 22.U, a biconvex lens-shaped obsidian artifact, also described as a mirror, measuring 250 mm in diameter and finely polished on both faces. It has usually been ascribed to the shipment sent by Hernán Cortez in 1522 to the Emperor Charles V, which was captured by a French privateer. We investigated the object using modern techniques. The elemental composition of the obsidian determined by the particle induced X-ray emission (PIXE) method showed that the raw material originates from the Mullumica deposit (Ecuador). Documentary investigations revealed that the lens (renumbered No. 176.101) was sent in 1737 from Quito, Ecuador (at that time part of the viceroyalty of Peru), to France by members of the Godin–La Condamine geodesic expedition (1735–1743). The mirror is thus among the rare Ecuadorian archeological or colonial artifacts to have reached the Old World during the eighteenth century. [ABSTRACT FROM AUTHOR]

Complex projectiles—propulsion via mechanical aid—are considered an important technological innovation, with possible relevance for the successful Out-of-Africa dispersal of our species. Conclusive evidence for the beginning of this technology, however, is lacking from the early Late Pleistocene (ca. 130 to 70 thousand years ago; ka). Given the extremely limited applicability of relatively robust methods for validating stone-tipped projectile use, such as through fracture propagation velocity, converging lines of circumstantial evidence remain the best way to examine early complex projectiles. We assess here suggestions for an early Late Pleistocene origin of complex projectiles in Africa. Results from both previous and present independent approaches suggest a trajectory in which complex projectiles were likely adopted during the early Late Pleistocene in eastern Africa. At Aduma (Middle Awash, Ethiopia), morphometric, hafting, and impact damage patterns in several lithic point assemblages suggest a shift from simple spear technologies (thrusting and/or hand-cast) to complex projectiles. Broadly dated to 80–100 ka, lithic points from later phases of the Aduma succession represent a particularly strong candidate for projectile armatures most comparable to ethnographically known spearthrower darts, lending support for previous suggestions and warranting further investigations. [ABSTRACT FROM AUTHOR]

The dominant emerging materials from more than 30 years ago are plastics, ceramics, and composite materials. Composite materials have steady growth in the volume and number of its applications as it enviably penetrates existing markets while creating new ones. Contemporary composite materials are well established in today's market of specialty and everyday products with its proven worth as weight-saving materials. There is a current challenge of cost-effectiveness and environmental friendliness, thus leading to the search for low-cost polymeric-reinforced composites using entirely biodegradable fibers. Bamboo fibers have provided some response in the production of materials that are recyclable, biodegradable, and sustainable. The natural fibers yield composites with high strength-to-weight ratios as a function of the best properties of each component. Researchers have found sustainable high-end quality industrial products that can be generated from raw materials like bamboo fibers. Due to its high strength-weight ratio, bamboo fibers are often used to replace natural glass fiber. Thus, the much attention has been given to its composites with different matrix materials. This article gives a review of recent developments of bamboo fiber-based reinforced composites, its processing methodology, and applications. [ABSTRACT FROM AUTHOR]

An exceptional discovery was made in 2013 in the northern French Alps, at the Grande Rivoire site in Sassenage (Isère department): an obsidian bladelet from Sardinia was found in a cultural horizon dated to about 5360-5210 CAL B.C. The abundant arrowheads found with it are characteristic of the Early Neolithic in the South of France (Cardial/Epicardial). Yet there was no pottery or domestic fauna, and only discrete markers of farming. The typological, technological and micro-wear analysis of this bladelet, as well as the determination of the origin of the raw material, open new avenues of reflection for the neolithization of the northern Alps, in particular concerning the role played by the Early Neolithic cultures of northern Italy. [ABSTRACT FROM AUTHOR]

Macroscopic characteristics, such as hardness, relatively easy workability, transparency, translucency, and shiny black colour of the Carpathian 1 (C1) type obsidian, which is one significant variety of the Carpathian obsidians made, it highly valuable in the Prehistoric times. It was transported several hundreds of kilometres away from the geological source, becoming wide-spread in the Eastern part of the Carpathian Basin as well. Seventy-two pieces of Prehistoric (Neolithic to Bronze Age) obsidian artefacts (tools, arrow heads, chips and fragments) found in different parts of Romania (Transylvania, Banat and Muntenia) have been investigated by non-destructive prompt-gamma activation analyses. The aim of the study was to determine the provenance of their raw materials. The geochemical composition of the artefacts showed high similarity with that of the obsidian samples collected at outcrops from the Slovakian side of the Tokaj Mountains. Based on characteristic major and trace element concentrations, most of the studied Romanian obsidian artefacts are characterized as C1 type obsidians. However, some archaeological pieces from Banat and Muntenia have been identified as Carpathian 2 (C2, Tolcsva-Erdőbénye and Mád) type. Based on the PGAA results, any other provenance, such as Lipari, Melos, Sardinia, Yali, Antiparos or Armenia can be excluded with high significance. Our results suggest that in parallel with the predominance of the C1 type obsidian raw material in the Transylvanian Basin, simultaneous use of C2 type obsidian raw material can be shown outside Transylvania (in Banat and Muntenia) and especially during the Neolithic. This can imply different connections and raw material supply routes from the Tokaj Mountains to Transylvania and to the southern regions during the Neolithic and the Copper Age. [ABSTRACT FROM AUTHOR]

Highlights • Ritual economy was used to understand bloodletting in Maya caves. • The ancient Maya used obsidian blades for bloodletting rituals. • Caves are locations for the performance of ancient Maya ritual. • Technological and use-wear analyses of obsidian blades from Actun Uayazba Kab, Belize. • Some obsidian blades from Actun Uayazba Kab were used for bloodletting. • Bloodletting was a means to generate political, economic, and ideological power and maintain status by ancient Maya elites. Abstract Ancient Maya material culture can be investigated from the perspective of ritual economy as a means to interpret the dynamic interrelationships between economic processes and the use of objects in ritual activities. Such interrelationships include access to raw materials, control of production and consumption, and the legitimate use of objects in various activities, including rites and performances, as constituted through a culture's worldview. This paper presents an exploration of the relationship between obsidian blades and bloodletting in Maya ritual contexts from the perspective of ritual economy, highlighting the use of blades in Actun Uayazba Kab (Handprint Cave) in Western Belize. The roles of producers, consumers, practitioners, and observers are examined in terms of gender, status, and power by tracing the functional and ideological characteristics of obsidian blades, as both objects used to let blood and as symbols of bloodletting, based on evidence derived from microscopic use-wear analysis and iconography. Ethnographic and ethnohistoric information is employed to assist in contextualizing ancient Maya ritual activity in caves and to provide a cultural lens to reconstruct how bloodletting was connected to resource production and consumption, the creation and maintenance of identity, and the allocation of power among Maya participants through ritual. [ABSTRACT FROM AUTHOR]

Lithic artifacts were still in use in Bronze Age Europe, in spite of the emergence of a new technology, namely metallurgy, during this period. In fact, stone technology continued to be used everywhere until at least the end of the Early Bronze Age, and even until the end of the Late Bronze Age in specific areas. This is especially true for Greece where lithic raw material and/or tool networks were still operating during the whole Bronze Age. During the Middle Bronze Age in mainland Greece, obsidian and high-quality chert were still widely used, especially in settlements. This raises the question of the necessity of the use of obsidian instead of a stronger or more versatile material (chert or metal). Why was volcanic glass, which required considerable investment in terms of know-how and long-distance transportation, still used in spite of the technological context (where metallurgy was already developed)? The purpose of this paper is to contribute to this debate through the use-wear analysis of obsidian tools. Artifacts from settlement levels of the Middle Helladic site of Kirrha (Phocis, Greece) have been examined. In this domestic-use context, bronze and chert were also found. The main results of this study show an exclusive form and use of obsidian: bladelets were used for cutting soft and siliceous plant matter, with the exception of Graminae harvesting activity. These results point to the specialization of the lithic industry in terms of raw materials, where sharp obsidian artefacts were employed for cutting of soft and flexible materials, depending on the relative brittleness of the rock, at least at Kirrha. Thus, among the numerous propositions concerning continued obsidian circulation during the entire Bronze Age, a functional use (at least) could be proven, if this observation is also made elsewhere in Greece. [ABSTRACT FROM AUTHOR]

The article includes the presentation and preliminary characterisation of the obsidian inventory obtained during the five research seasons (2014-2018) at the site in Podlesie, Staszów district, Świętokrzyskie voievodship. Currently, it is one of the largest collections of artefacts of this raw material related to the Linear Pottery culture (104 examples), and at the same time the first obtained from the Połaniec Basin mesoregion. In the light of the current state of research, it is also one of the few inventories of this culture (outside the Rzeszów settlement cluster), in which the share of obsidian exceeded 4%. Its homogeneous nature and large size, as well as the obtained radiocarbon dates, to a very significant extent supplement the current knowledge about the initial phase of the Neolithic obsidian influx into the Upper Vistula basin area, at the end of the 6th millennium BC. [ABSTRACT FROM AUTHOR]

Timor-Leste is known for long-term continuity in lithic manufacturing techniques that span at least the last 44,000 years. Here we confirm this pattern of long-term continuity in stone tool manufacture at the site of Matja Kuru 2, located on Timor-Leste close to the freshwater Lake Ira Lalaro. The lithic assemblage is characterised by high reduction intensity and frequent use of bipolar, 'core-on-flake', discoidal and multiplatform core reduction to produce small flakes while high levels of retouch, heat damage and breakage. While continuity is an important feature of the assemblage, we also document important changes in technology, raw material selection and recycling/extension strategies over time. We posit that the long periods of absence at MK2 may coincide with drier phases when Ira Lalaro likely dried and that more extensive use of the cave occurs during wet phases with attendant lake high conditions. The lithic assemblage indicates increased mobility and individual provisioning in the transitions between these phases of site use and abandonment. The Matja Kuru 2 lithic assemblage also reveals the earliest known evidence yet found for obsidian and possible inter-island transport in Wallacea. • Matja Kuru 2 displays long-term continuity in stone artefact manufacture. • Long periods of human absence are documented at the site that coincide with drier climate phases. • Phases of intense site use correspond well with those documented at other sites across the Nusa Tenggara region of Island Southeast Asia. • Evidence exists for increased mobility and changes in provisioning strategies at the transitions between the three phases of site use. • Matja Kuru 2 reveals the earliest known evidence for obsidian and possible inter-island transport in Wallacea. [ABSTRACT FROM AUTHOR]

Arslantepe is a höyük (= tell) located within the fertile Malatya Plain, near the right bank of the Euphrates River. The site is excavated since more than 55 years by the Italian Sapienza University archaeologists and reveals periods from at least the sixth millennium BCE until the final destruction of the Neo-Hittite town. This long sequence records the changing relations and connections with various civilizations and regions of the Near East. Using the chemical characterization of a large group of artefacts (388 analysed), we propose, in this paper, a new sourcing of the obsidian used by the inhabitants of Arslantepe from the beginning of the Late Chalcolithic to the end of the Early Bronze Age. The method is based on the portable XRF analyse of the artefacts and their attribution to a geological source using our database collected within the ongoing “GeObs” project (resp. D. Mouralis) in the Eastern Anatolia as well as previous published data in Central Anatolia and Caucasus. Moreover, the chemical characterization is coupled with the techno-functional determination of the artefacts. The present study conducted by an interdisciplinary research group allows to precise the procurement of obsidian in Arslantepe and to better understand the external relations of the site over time. This research also questions and discusses the preferential choice of the obsidian sources through time, in relation with various factors such as distance, quality and abundance of the raw material as well as socio-cultural influences. [ABSTRACT FROM AUTHOR]

This paper aims to study and compare the obsidian economies of Renaghju and I Stantari, two neighbouring Neolithic sites located on the Cauria plateau (south-western Corsica). The occupation phase 3 of Renaghju and phase 1 of I Stantari, both attributed to the Middle Neolithic (fifth millennium BC), have provided respectively 112 and 99 obsidian artefacts. With the aim of completing our rather lacunary knowledge of the obsidian consumption behaviours in place in Corsica during this period, the entire assemblages have been geochemically characterised virtually non-destructively using LA-ICP-MS at SOLARIS (Southern Cross University [SCU]). Our analyses revealed that, while the obsidian raw materials were exclusively sourced from the Monte Arci complex in Sardinia (SA, SB2, and SC sub-types only), rather different consumption patterns are observed for the two sites despite their comparable nature (megalithic sites) and geographical proximity (400 m apart). These differences in obsidian consumption on adjacent sites could be explained by their divergent functions (ceremonial site [Renaghju] vs . ceremonial locus and large settlement [I Stantari]), or eventually point towards the need for a readjustment of the chronological attribution of the I Stantari phase 1 occupation level. [ABSTRACT FROM AUTHOR]

The article focuses on the chronological status of the distribution of 'chocolate' silicite originating from the area of south-east Poland in the prehistory of the Czech lands. The flow of 'chocolate' silicite across the Carpathian Mountains culminated in the period of the Stroke-Ornamented Ware culture (5100/5000-4500/4400 cal BC) in the area studied. Based on the analysis of the contexts of finds and the classification of the artefacts, the raw material is interpreted as an indicator of the presence of individuals or groups with an exclusive social status. Both the pattern of distribution and the status are common to other 'exotic' raw materials, especially for Carpathian obsidian, in the studied area in that same period. By comparing the spatial and chronological image expansion of both materials can lead to similar conclusions in their assessment. [ABSTRACT FROM AUTHOR]

Obsidian provenance studies, conducted in Northeast Asia over the last 40 years, give us solid evidence about human migrations and contacts in prehistory. Active exchange of raw material began at ca. 33,000–25,000 BP in both the mainland and insular parts of this region, and continued afterward. The scale of interaction between Stone Age people was quite large, with distances sometimes greater than 800–1000 km in later prehistory. Seafaring was most probably practiced since this time, as supported by the movement of obsidian across wide (20–40 km) open sea. [ABSTRACT FROM AUTHOR]

The current state-of-the-art of provenance studies for archaeological obsidian on Kamchatka Peninsula is presented. Prehistoric people widely used obsidian as a raw material for making tools, and acquired it from several primary sources. The exact position of seven sources allowed us to understand the general features of obsidian geochemistry and tectonic position of obsidian-bearing volcanic formations. This also made it possible to suggest the localization of seven still unknown sources for archaeological obsidian on Kamchatka. Verification of our preliminary conclusions can be made by fieldwork in selected areas. [ABSTRACT FROM AUTHOR]

Strategies employed by Middle Palaeolithic hominins to acquire lithic raw materials often play key roles in assessing their movements through the landscape, relationships with neighboring groups, and cognitive abilities. It has been argued that a dependence on local resources is a widespread characteristic of the Middle Palaeolithic, but how such behaviors were manifested on the landscape remains unclear. Does an abundance of local toolstone reflect frequent encounters with different outcrops while foraging, or was a particular outcrop favored and preferentially quarried? This study examines such behaviors at a finer geospatial scale than is usually possible, allowing us to investigate hominin movements through the landscape surrounding Lusakert Cave 1 in Armenia. Using our newly developed approach to obsidian magnetic characterization, we test a series of hypotheses regarding the locations where hominins procured toolstone from a volcanic complex adjacent to the site. Our goal is to establish whether the cave's occupants procured local obsidian from preferred outcrops or quarries, secondary deposits of obsidian nodules along a river, or a variety of exposures as encountered while moving through the river valley or across the wider volcanic landscape during the course of foraging activities. As we demonstrate here, it is not the case that one particular outcrop or deposit attracted the cave occupants during the studied time intervals. Nor did they acquire obsidian at random across the landscape. Instead, our analyses support the hypothesis that these hominins collected obsidian from outcrops and exposures throughout the adjacent river valley, reflecting the spatial scale of their day-to-day foraging activities. The coincidence of such behaviors within the resource-rich river valley suggests efficient exploitation of a diverse biome during a time interval immediately preceding the Middle to Upper Palaeolithic “transition,” the nature and timing of which has yet to be determined for the region. [ABSTRACT FROM AUTHOR]

The Oldowan Industrial Complex has long been thought to have been static, with limited internal variability, embracing techno-complexes essentially focused on small-to-medium flake production. The flakes were rarely modified by retouch to produce small tools, which do not show any standardized pattern. Usually, the manufacture of small standardized tools has been interpreted as a more complex behavior emerging with the Acheulean technology. Here we report on the ~1.7 Ma Oldowan assemblages from Garba IVE-F at Melka Kunture in the Ethiopian highland. This industry is structured by technical criteria shared by the other East African Oldowan assemblages. However, there is also evidence of a specific technical process never recorded before, i.e. the systematic production of standardized small pointed tools strictly linked to the obsidian exploitation. Standardization and raw material selection in the manufacture of small tools disappear at Melka Kunture during the Lower Pleistocene Acheulean. This proves that 1) the emergence of a certain degree of standardization in tool-kits does not reflect in itself a major step in cultural evolution; and that 2) the Oldowan knappers, when driven by functional needs and supported by a highly suitable raw material, were occasionally able to develop specific technical solutions. The small tool production at ~1.7 Ma, at a time when the Acheulean was already emerging elsewhere in East Africa, adds to the growing amount of evidence of Oldowan techno-economic variability and flexibility, further challenging the view that early stone knapping was static over hundreds of thousands of years. [ABSTRACT FROM AUTHOR]

Obsidian raw material has been widely used in central and southern Patagonia from the beginning of the occupation of this region. In NW Santa Cruz province, Argentina, the geochemical analyses published to date suggest that Pampa del Asador was the main obsidian source. However, both the spatial and temporal limits of the distribution of obsidians from this and other sources in the region remain undefined. The principal goal of this article is to characterize obsidian artifacts from archaeological sites, located in a portion of NW Santa Cruz, from which there is no available geochemical information. ICP-MS analyses were obtained for 49 obsidian artifacts recovered from 24 excavated rockshelters and open-air surface scatters. The results indicate that all the samples of black obsidian came from the Pampa del Asador source, located ∼90–160 km to the south. Two samples of grey obsidian discovered on the top of Meseta del Lago Buenos Aires are chemically different from any other archeological obsidian yet analyzed in southern Patagonia. Their origin is still unknown, but they are most likely derived from a local Meseta del Lago Buenos Aires obsidian source. These results contribute to the knowledge about the use of obsidian in NW Santa Cruz, and provide constraints on the communication and material exchange between different environments and basins in this region. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to begin to understand human mobility through rock transport at different times in two areas with different environmental characteristics: the Southern Deseado Massif and the basaltic canyons north of the Santa Cruz River. We focus on obsidian, which has a clear geochemical signature and an uneven distribution. Additionally, we use macroscopic information on siliceous rocks, which at present have only been identified in northern areas, although they may also be recovered randomly and in low frequencies in southern ones. During the initial peopling of the Southern Deseado Massif (ca. 10,800 BP), inhabitants were transporting black obsidian as well as translucent chalcedony, probably as part of the individual gear. During the Late Holocene, the number of obsidian artifacts decreased in the Southern Deseado Massif, related to a better knowledge of the high-quality local lithic resources and/or to the existence of higher population densities. Obsidian artifacts are more abundant in the northern Santa Cruz River basin than in the southern Deseado Massif, suggesting the existence of a relationship with areas located to the northwest, close to the obsidian source, as other lines of evidence suggest. In addition, the presence in the basaltic canyons of artifacts made from high-quality siliceous rocks, more abundant and predictable in northern areas, could also be the result of human movements following a north-south direction. [ABSTRACT FROM AUTHOR]

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