Worked Materials Research Articles

Measuring use-wear striations on quartz. First results from an ongoing study

Inspired by earlier observations of use-wear on quartz, a pilot study has been undertaken, in which characteristics of microscopic striations have been linked to the properties of contact materials. Through a series of experiments, un-hafted and un-modified quartz flakes were used to cut different raw materials. Striations produced in the experiments were then studied via microscope using a high powered method. By comparing striations between the different experimental flakes, effects of the worked material could be observed. The results were then further tested by studying the collected joint length and width data through a statistical analysis. This analysis indicates how such data may distinguish different worked materials, and in particular are related to the relative hardness of the material. Though the role of environmental variation is not yet fully realized, the study has made evident that length and width of the use-wear striations should be considered important as they together have the potential to distinguish between different contact materials.

The effect of worked material hardness on stone tool wear.

The identification of ancient worked materials is one of the fundamental goals of lithic use wear analysis and one of the most important parts of understanding how stone tools were used in the past. Given the documented overlaps in wear patterns generated by different materials, it is imperative to understand how individual materials’ mechanical properties might influence wear formation. Because isolating physical parameters and measuring their change is necessary for such an endeavor, controlled (rather than replicative) experiments combined with objective measurements of surface topography are necessary to better grasp how surface modifications formed on stone tools. Therefore, we used a tribometer to wear natural flint surfaces against five materials (bone, antler, beech wood, spruce wood, and ivory) under the same force, and speed, over one, three, and five hours. The study aimed to test if there is a correlation between surface modifications and the hardness of the worked material. We measured each raw material’s hardness using a nano-indentation test, and we compared the surface texture of the flint bits using a 3D optical profilometer. The interfacial detritus powder was analyzed with a scanning electron microscope to look for abraded flint particles. We demonstrate that, contrary to expectation, softer materials, such as wood, create a smoother surface than hard ones, such as ivory.

Effects of cold work on the corrosion behavior of Alloy 800H exposed to aerated supercritical water

• Cold work reduces the corrosion resistance of Alloy 800H in supercritical water containing 200 ppb oxygen. • At initial corrosion stage, the corrosion behavior of as-received and cold-worked materials is similar. • The formation of a continuous chromia layer reduces the oxygen partial pressure at the oxide scale-matrix interface, which contributes to the later internal oxidation and selective oxidation of the elements. • With the increase of exposure time, the microstructure of the cold worked materials becomes more complicated and is further subdivided into Fe 3 O 4 /Ni x Fe 3- x O 4 /Ni x Fe y Cr 3- x - y O 4 /Cr 2 O 3 / NiO/Fe x Cr 2- x O 4 +pure Ni multi-layer structure. • Through observation of the oxidation process and the calculation of thermodynamic equilibria, the oxide scale differences were explained through the hypothesis that diffusion barriers were created by the prevailing oxides. Revealing the corrosion mechanism of materials in supercritical water (SCW) is a key issue for the development of a supercritical water reactor (SCWR). Considering cold work is inevitable in the construction of nuclear reactors and its effect on the corrosion behavior of materials in SCW is still unclear, the corrosion behavior of solution-annealed (as-received) and 30% cold-worked Alloy 800H were studied at 600 °C in aerated SCW for 1500 h. The microstructure of the oxide scale was studied by a variety of characterization techniques. The results indicate that cold work increases the corrosion rate of the materials, promotes selective oxidation and internal oxidation, and this was attributed to the high diffusion rate of different ions along “short-circuit paths”. The oxide scale composition and structure of the cold-worked material, which is subdivided to Fe 3 O 4 /Ni x Fe 3- x O 4 /Ni x Fe y Cr 3- x - y O 4 /Cr 2 O 3 /NiO/ Fe x Cr 2- x O 4 + pure Ni multi-layer structure, are much more complicated than the as-received material after 1500 h exposure. Combined with the thermo-dynamic equilibrium calculation, the oxidation processes of the as-received and cold-worked materials were analyzed to reveal the effect of cold work on the corrosion behavior of Alloy 800H.

Quantitative use-wear analysis of stone tools: Measuring how the intensity of use affects the identification of the worked material.

The identification of the use of stone tools through use-wear analysis was one the major methodological advances in Prehistoric Archaeology during the second half of the 20th century. Studies of use-wear analysis have decisively contributed to a better understanding of the cognitive capacities and the socio-economic organization of Prehistoric societies. Among use-wear traces, microwear polish is the most relevant evidence, as it allows the identification of the worked materials (i.e. wood, antler, hide, bone, stone…). This identification is currently carried out through the qualitative and visual comparison of experimental and archaeological tools. During the last decade, confocal microscopy is allowing the quantitative identification of the worked material through the texture analysis of microwear polish. Previous tests have accounted for the variability of use-wear traces as caused by different types of worked material. However, how the intensity of use, which is widely recognized as an important factor conditioning microwear polish characteristics, affects our capacity to identify the worked materials is poorly understood. This research addresses the dynamic nature of microwear polish through confocal microscopy and texture analysis. This research shows that use-wear polishing is a dynamic process and surface texture evolves continuously during the working time. The evolution fits a logarithmic function, so most texture modification takes place during the first phases of work. The way in which polish texture evolves through time differs from one contact material to the other. We demonstrate that, despite the dynamic nature of use-wear polish, different worked materials can be discriminated. However, some overlapping between used and unused surfaces and between worked materials occurs in the first stages of use. Moreover, polishes of similar characteristics (i.e. bone and antler) can show similar texture at advanced stages of use. These problems in identification can be in good measure overcome by creating dynamic models of polish texture in which not only the worked material but also the time of use is considered.

The Middle Paleolithic ground stones tools of Nesher Ramla unit V (Southern Levant): A multi-scale use-wear approach for assessing the assemblage functional variability

In the archaeological record, Ground Stone Tools (hereafter GST) represent an important tool group that provides invaluable data for exploring technological development and changes in resource exploitation over time. Despite its importance, Lower and Middle Paleolithic (MP) GST technology remains poorly known and understudied. The MP record of the Levant constitutes a compelling case study for exploring the nature and character of GST technology. Especially the site of Nesher Ramla (Israel, end of Marine Isotope Stage 6/beginning of 5) has provided one of the world's largest GST assemblages from MP contexts.Aiming at evaluating the variability of tool types at the site from a technological and functional perspective, this study follows an analytical approach which integrates different scales of analysis. Our workflow seeks to generate and combine qualitative and quantitative data allowing: 1) the identification of damage areas, and 2) functional analysis, based on the location, distribution, and characterization of use-wear traces.This study shows a substantial level of diversification in resource exploitation (e.g., mineral, hard animal material and likely perishable components). Results show the presence of several tool types on which diagnostic use-wear can be associated with different activities. Importantly, our analysis indicates the presence of various hammerstone types showing distinct wear characteristics. The variability observed within the hammerstones likely reflects different functions, including in some cases the processing of distinct worked materials. Ultimately, this study contributes to our understanding of the significance of GST technology for the ecological dynamics of MP populations.

Ein Schweizer Taschenmesser des Jungpaläolithikums? Experimente zu nicht jagdwaffenbezogenen Verwendungen von Rückenmessern

Backed lithic artifacts are an important part of the Upper Paleolithic tool kit, and are often among the most abundant categories of lithic tools found at Magdalenian and Gravettian sites. Often these tools are exclusively referred to as projectiles, and indeed many – if not most – backed pieces may have been parts of composite projectile heads, mounted laterally onto organic points (e.g., Allain and Descouts 1957; Allain 1979; Abramova 1982; Bergman and Newcomer 1983; Leroi­ Gourhan 1983; Plisson 1985; Nuzhnyi 1993; Christensen and Valentin 2004; Sano 2009; Langlais 2010; Araujo­Igreja 2011; Tomasso et al. 2018). Experiments of varying comprehensiveness concerned with the use of (Magdalenian) backed pieces as projectile inserts have confirmed the effectivity of this setup (e.g., Moss and Newcomer 1982; Pétillon et al. 2011; Gauvrit Roux et al. 2020). However, backed pieces sometimes also served other purposes like cutting, sawing, shaving, scraping or perforating (Moss and Newcomer 1982; Moss 1983; Owen 1988; Piel­Desruisseaux 1998; Christensen and Valentin 2004; Taller et al. 2012). The modular technological system involving these lithic artifacts is highly versatile, mobile and dynamic as there are numerous possibilities of use and as the small lithic inserts are easy to transport and the composite tools themselves are easy to maintain and repair. Here, we present the results of an experiment where different tasks were carried out using backed pieces hafted in a wooden handle or operated handheld. The design of the handles loosely follows examples found at Canadian Dorset sites where bladelets comparable in size to Magdalenian backed pieces were hafted and used as knives (Owen 1988, 88ff.). We tried out the tools in various activities (cutting, perforating and carving/whittling) on a set of worked materials (wood, antler, marine shell, smoked meat, dried, semi­tanned hide, and tanned leather). After the completion of these tasks, the applicability, durability and usefulness of the setup were evaluated and the lithic inserts were checked microscopically for use­wear traces.

Polish is quantitatively different on quartzite flakes used on different worked materials

Metrology has been successfully used in the last decade to quantify use-wear on stone tools. Such techniques have been mostly applied to fine-grained rocks (chert), while studies on coarse-grained raw materials have been relatively infrequent. In this study, confocal microscopy was employed to investigate polished surfaces on a coarse-grained lithology, quartzite. Wear originating from contact with five different worked materials were classified in a data-driven approach using machine learning. Two different classifiers, a decision tree and a support-vector machine, were used to assign the different textures to a worked material based on a selected number of parameters (Mean density of furrows, Mean depth of furrows, Core material volume-Vmc). The method proved successful, presenting high scores for bone and hide (100%). The obtained classification rates are satisfactory for the other worked materials, with the only exception of cane, which shows overlaps with other materials. Although the results presented here are preliminary, they can be used to develop future studies on quartzite including enlarged sample sizes.

Experimental approaches to the development of use-wear traces on volcanic rocks: basalts

In this paper we present the experimental results obtained for the formation of use-wear traces on four types of basalt rocks from the Olduvai Gorge (Tanzania) and one from the Deba River (Spain). The objective of this study is to create a reference collection that will allow the posterior analysis and identification of archeological use-wear traces on lithic industries made on these different types of basalt, such as the Acheulean lithic industry from Thiongo Korongo site (TK) (Olduvai’s Bed II, ca. 1.353 ± 0.035 Ma.). This study includes five types of basalt, under the objective of understanding in more detail the formation of the use-wear traces. Additionally, we include their individual petrographic, chemical, and traceological interpretations, allowing for an assessment of the intrinsic characteristics in relation to the development of use-wear. The final step of this process includes microscopic analysis for the detailed characterization and description of these use-wear traces. The results obtained reveal the internal structure of basalts as a significant conditioning factor in the development of use-wear traces. Despite this, we have been able to establish several criteria that discriminate between actions and different worked materials. These results offer a fundamental experimental basis for the future interpretation of use-wear traces found in archeological basalts.

Butchering or wood? A LSCM analysis to distinguish use-wear on stone tools

Traceological method is based on the identification and analysis of the stone tools surface modifications as a result of the use, hafting or manufacturing procedures, among others. Traditionally, use-wear analyses have been conducted using Optical Light Microscopy (OLM) or even, Scanning Electron Microscopy (SEM), normally basing the interpretations on subjective descriptions. Although there are general protocols successfully followed and good results in this field, researchers have always been conscious about the need to advance towards a quantitative an objective method. In response to that concern, techniques as Laser Scanning Confocal Microscopy (LSCM) are being applied successfully to functional analyses, thus improving the metrological studies.The main goal of this research is the characterization and quantification of those alterations caused by butchering activities in comparison with unused areas in order to recognize modification patterns on the chert natural surface. Wood working has been also included in this study as a comparative sample. Also, a quantitative distinction between micropolishes produced by butchering activities and wood working has been carried out. The results show that discrimination between unused areas and wood micropolishes is possible. Meanwhile, butchering activities modify lightly the chert surface. On the other hand, quantitative parameters statistically differ between worked materials proving this method to be useful to identify them.

PEMANFAATAN ALAT SERPIH DI CERUK LAYAH KECAMATAN SAMPUNG, KABUPATEN PONOROGO, JAWA TIMUR (BERDASARKAN KAJIAN MIKROSKOPIS JEJAK PAKAI DENGAN PERBESARAN RENDAH)

Ceruk Layah is a site that located in Sampung Karst Region, Ponorogo, East Java. Based on the result of excavation conducted by Balai Arkeologi Yogyakarta in the ear of 2000-2002, the finds were dominated by stone artefacts and pottery fragments. Techno-economy study and stone artefacts classification had been done macroscopically. Further analysis is needed to ascertain whether stone tools in Ceruk Layah had been utilized by its occupants. There are three questions, concerning the variation of microware of the flake tools, the utilization of the flake tools, and the resistance of the worked materials on flake tools. This study applies macroscopic and microscopic analysis. Macroscopic analysis aims to determine the dimension, material, distribution, and location of microware of the flake tools. While microscopic analysis aims to identify the microware of flake tools by using low magnification (50 X), and to measure the depth and length of the fracture of the flake tools. The objective of the measurements of the fracture is to distinguish the fracture caused by flaking and utilization of the flake tools. The results of analysis shows that the sixteen pieces of flake tools in the Ceruk Layah carries three microwares which were dominated by fracture, while striation and polish were rarely found. In addition, each flake tool carries fracture that varies on the length and depth. The flake tools of Ceruk Layah might have been used for cutting, whittling, sawing, scraping, and boring. The resistance of the worked material consists of soft resistance, moderate resistance, and hard resistance.

Identifying Experimental Tool Use Through Confocal Microscopy

Characterizing use-wear traces quantitatively is a valid way to improve the capacity of use-wear analysis. This aim has been on specialists’ agenda since the beginning of the discipline. Micropolish quantification is especially important, as this type of trace allows the identification of worked materials. During the last decade, confocal microscopy has been used as a promising approach to address this question. Following previous efforts in plant microwear characterization (Ibanez et al. Journal of Archaeological Science, 48, 96–103, 2014; Journal of Archaeological Science, 73, 62–81, 2016), here we test the capacity of the method for correctly grouping experimental tools used for working eight types of materials: bone, antler, wood, fresh hide, dry hide, wild cereals, domestic cereals, and reeds. We demonstrate, for the first time, that quantitative texture analysis of use-wear micropolish based on confocal microscopy can consistently identify tools used for working different contact materials. In this way, we are able to move toward using texture analysis as part of the standard functional analysis of prehistoric instruments.

Расчетное прогнозирование влияния технологических условий обработки на эксплуатационные свойства деталей машин

The paper reports theoretical dependences defining a correlation of technological processing conditions (cutting modes, tool tip geometry, properties of worked and tool materials), quality parameters of a surface layer (surface roughness, degree and depth of cold work, residual stresses) and performance properties of machinery (fatigue resistance, wear-resistance, contact rigidity, press-fit connection strength) which can be used in a team-work of a designer and a technologist at simultaneous technological pre-production.

Wear analysis on EN8, EN9 and EN24

PurposeThis paper aims to present a comparative study of the wear properties of ferrous welded materials like EN8, EN9 and mild steel (MS).Design/methodology/approachThe material is cut into specific dimension after hardfacing and is studied for the wear properties of the material. The wear testing is done on a pin-on-disc apparatus. The microhardness of the material is studied using the Vickers microhardness measuring apparatus.FindingsThe wear properties of ferrous welded materials like EN8, EN9 and MS are studied. It is found the MS has the least wear when compared to EN8 and EN9. The microhardness of MS is higher than EN8 and EN9, thus making it more wear-resistant than EN8 and EN9. The coefficient of friction in the dry sliding condition is found to be constant throughout the experiment.Research limitations/implicationsMajor restriction is the amount of time required for use-wear analysis and replication experiments that are necessary to produce reliable results. These limitations mean that the analysis of total assemblages with the intention of producing specific results, especially of worked materials, is not feasible.Practical implicationsGenerally, the complexity and rigour of the analysis depend primarily on the engineering needs and secondarily on the wear situation. It has been the author’s experience that simple and basic wear analyses, conducted in the proper manner, are often adequate in many engineering situations. Integral and fundamental to the wear analysis approach is the treatment of wear and wear behaviour as a system property. As a consequence, wear analysis is not limited to the evaluation of the effects of materials on wear behaviour. Wear analysis often enables the identification of nonmaterial solutions or nonmaterial elements in a solution to wear problems. For example, changes in or recommendations for contact geometry, roughness, tolerance and so on are often the results of a wear analysis.Originality/valueThe value of the work lies in the utility of the results obtained to researchers and users of the EN8, EN9 and EN24 material for their components.

Monitoring and interpreting the use-wear formation processes on quartzite flakes through sequential experiments

Abstract Sequential experiments were performed with quartzite flakes with the main purpose of monitoring use-wear formation processes. The two main objectives of this research were the construction of a wide reference collection to serve for future functional interpretations of the archaeological material and to achieve a better comprehension of the mechanical behaviour of quartzite when subjected to the stress applied in determined prehistoric tasks (e.g., sawing, scraping bone, wood, etc.). The two objectives are strictly related because the appearance of wear on the tool edges resulting from those tasks would be dependant on the mechanical behaviour of the rock in question. Concepts from tribology were used to provide an explanatory framework. As mechanical behaviour of solid materials always depends on their mechanical proprieties which are unique, each raw material should be treated individually in use-wear analysis. For this reason, there is an urgent need to create a reliable and objective system to identify and interpret wear due to use on quartzite. For data recording, we resorted to both optical and electron microscopes (OLM and SEM) to present a wide photographic documentation and to compare the adequacy and complementarity of those microscopic techniques for microwear studies. Furthermore, both the experimental residues of the worked materials and the rock particles detached from the active edges were analysed to understand their role as interfacial medium affecting use-wear formation. EDX (Energy- Dispersive X-ray spectroscopy) was used to document the presence of rock particles detached from the tools edges and then embedded in the residues of the worked materials. The results from analysing the experimental flakes allowed us to infer more closely the mechanical behaviour of quartzite. As a final point, the potential of OLM and SEM for analysing quartzite surfaces was evaluated and it emerged that the combination of the two techniques in an integrated approach is a feasible choice, though the application of SEM is always desirable in order to get more trustworthy results.

Reconstructing Harvesting Technologies through the Analysis of Sickle Blades: A Case-Study from Early-Middle Neolithic Sites in Northeastern Italy

The study of the crop-harvesting technology of the first groups of farmers can notably contribute to the debate on the expansion of agriculture in the Central Mediterranean. The traceological analysis of so-called “sickle blades” represents a valuable proxy for studying the emergence of harvesting technologies during Early Neolithic and their geographic variability. Use-wear traces allow to reconstruct the way in which the tool was used, the type of worked materials, the type of motion and the hafting of the flint blades. In this paper, we present the result of the analysis of a sample of sickle blades from two Early Neolithic settlements in northeastern Italy: Sammardenchia and Piancada. Those sites are particularly interesting because of their location in an area that is a natural crossroad between southern and central Europe and between the eastern and the western Mediterranean. Comparing our results with data obtained from other Neolithic sites of the Italian Peninsula, two different types of sickles have been recognized: sickles with diagonally hafted blades in southern and central Italy and sickles with parallel hafting in the Padan-Alpine region. In our opinion, such a dichotomy might be the result of different paths of diffusion of the agricultural technologies.

On Quina and demi-Quina scraper handling: Preliminary results from the late Lower Paleolithic site of Qesem Cave, Israel

Most of the studies related to the function of Paleolithic stone tools carried out so far focused mainly on the analysis of the worked materials and the activities performed. On the other hand, only few works included an analysis of the tool griping area/s, and the wear derived by object manipulation. Here we present the results of an experimental framework dedicated to the interpretation of the griping modes of two types of flint scrapers, Quina and demi-Quina scrapers, which represent a very meaningful component of the lithic assemblages unearthed at the late Lower Paleolithic site of Qesem Cave (Israel).Our study includes the analysis of both a selected sample of archeological scrapers and of experimental replicas. We were able to underline the efficiency of different types of prehension modes while isolating diagnostic wears related to each of the adopted solutions. The experiments allowed defining wears related to several handling solutions, creating a traces collection to be compared to the ones identified on the archeological sample. The results obtained so far suggest a preference towards a free hand manipulation of the scrapers, even though wear related to wrapping and also to a probable insertion of the objects in a haft have been identified as well. This work allows providing preliminary insights related to the handling solutions adopted by the human groups at Qesem Cave, underlining the overall high level of technological knowledge characterizing the Middle Pleistocene inhabitants of the site.

Surface analysis of stone and bone tools

Microwear (use-wear) analysis is a powerful method for identifying tool use that archaeologists and anthropologists employ to determine the activities undertaken by both humans and their hominin ancestors. Knowledge of tool use allows for more accurate and detailed reconstructions of past behavior, particularly in relation to subsistence practices, economic activities, conflict and ritual. It can also be used to document changes in these activities over time, in different locations, and by different members of society, in terms of gender and status, for example. Both stone and bone tools have been analyzed using a variety of techniques that focus on the observation, documentation and interpretation of wear traces. Traditionally, microwear analysis relied on the qualitative assessment of wear features using microscopes and often included comparisons between replicated tools used experimentally and the recovered artifacts, as well as functional analogies dependent upon modern implements and those used by indigenous peoples from various places around the world. Determination of tool use has also relied on the recovery and analysis of both organic and inorganic residues of past worked materials that survived in and on artifact surfaces. To determine tool use and better understand the mechanics of wear formation, particularly on stone and bone, archaeologists and anthropologists have increasingly turned to surface metrology and tribology to assist them in their research. This paper provides a history of the development of traditional microwear analysis in archaeology and anthropology and also explores the introduction and adoption of more modern methods and technologies for documenting and identifying wear on stone and bone tools, specifically those developed for the engineering sciences to study surface structures on micro- and nanoscales. The current state of microwear analysis is discussed as are the future directions in the study of microwear on stone and bone tools.

Structural study of two quartzite varieties from the Utrillas facies formation (Olmos de Atapuerca, Burgos, Spain): From a petrographic characterisation to a functional analysis design

Abstract This overall research initiative was undertaken to evaluate the role of lithic raw material variability in use-wear formation processes, focusing specifically on two lithological varieties of quartzite present in the Lower and Middle Pleistocene lithic assemblages of the Gran Dolina, Galeria and Sima del Elefante sites (Sierra de Atapuerca, Burgos). Two Arenas de Utrillas facies varieties (from a sand quarry located in Olmos de Atapuerca) were studied using petrographic and SEM analyses. They were both identified as metaquartzites, revealing differences in their granular structure and metamorphic grade. Sequential experiments employing the same quartzite varieties were then conducted involving different activities and several worked materials, which made it possible to determine use-wear formation on these two quartzite varieties. The results helped to clarify the role of intra-raw material variability in the process of use-wear formation on quartzite and contributed to ongoing studies of the lithic materials from these archaeological sites.

Influence of Semi-Solid Casting and Equal Channel Pressing on Microstructure of a Hypoeutectic Al-Si Alloy

The aim of this work was to develop understanding of microstructural evolution of the alloy casted in semi-solid condition using a cooling slope and conventional casting followed by ECAP in a 120o die. Feed materials were prepared by cooling slope casting and conventional casting for ECAP process. The microstructures and Vickers hardness of the worked materials extruded by two routes (A and BC) were evaluated. The primary α-Al phase tends to be elongated after processing by route A. However, its morphology was similar in nature to the microstructure of the as-cast sample after processing by route BC. The Si particles become fragmented during ECAP processing and are more nearly globular in shape and uniform in size than in the as-cast sample. The microstructure of the semi-solid cast ECAPed samples was more homogenous than that of the conventional cast ECAPed sample followed by ECAP for both routes. The hardness of semi-solid cast ECAP samples was also higher than that of conventional cast ECAPed samples for both routes.

What were the recycled potsherds used for? Use-wear analysis of Early Neolithic ceramic tools from Bulgaria (6100–5600 cal. BC)

Many potsherds recycled as tools have been discovered in the Early Neolithic ceramic assemblages of south-western Bulgaria (6100–5600 cal. BC). Their large quantity has raised the issue of the role of this industry in the economy of the first farming societies in the Balkans. The scarcity of use-wear analyses on the ceramic tools has required the development of an observation protocol adjusted to archaeological recycled potsherds coupled with the construction of a wide experimental reference. The study method has allowed the determination of the macro- and microscopic characteristics of use-wear that are diagnostic of worked materials, kinematics and use-time of ceramic tools. It has highlighted their technical functions which prove to be extremely diversified in the Early Neolithic of south-western Bulgaria: spindle whorls, tokens, hide scrapers or potter's ribs and smoothers. The broad use-range of ceramic tools, as well as their large quantity, shows the recycled potsherds were not occasional substitutes of bone and lithic objects. On the contrary, they were fully integrated in the Neolithic toolkits for carrying out certain technical productions.