Source provenance of obsidian artifacts from the Early Stone Age (ESA) site of Melka Konture,Ethiopia

The source provenance of 10 Early Stone Age artifacts from the localities in Melka Konture has been determined by EDXRF. Results show that the early to mid-Pleistocene makers of the artifacts derived the raw material from a source located in their proximity, supporting the previously proposed short distance transport of raw material for the time period.     

CHEMICAL–MINERALOGICAL ANALYSES AND MICROSTRUCTURAL STUDIES OF PREHISTORIC POTTERY FROM RAHMATABAD,SOUTH‐WEST IRAN*

A series of prehistoric pottery samples excavated from Rahmatabad, south‐west Iran, were investigated using XRF and XRD analyses to determine their chemical and mineralogical compositions. The sample microstructures were also studied by SEM/EDX. The relative similarity of compositions, the fine, dense and homogeneous microstructures and the presence of high‐temperature phases such as diopside and mullite showed the use of high firing temperatures, in the range 950–1050°C. This, along with the homogeneity in shape, decoration and size ranges of the ware, all indicate the adoption of specialized pottery‐making techniques by the potters of Rahmatabad in the fifth to fourth millennia bc .     

Initial source evaluation of archaeological obsidian from the Kuril Islands of the Russian Far East using portable XRF

Obsidian artifacts recently have been recovered from 18 archaeological sites on eight islands across the Kuril Island archipelago in the North Pacific Ocean, suggesting a wide-ranging distribution of obsidian throughout the island chain over the last 2,500 years. Although there are no geologic sources of obsidian in the Kurils that are known to have been used prehistorically, sources exist in Hokkaido, Japan, and Kamchatka, Russia, the southern and northern geographic regions respectively from which obsidian may have entered the Kuril Islands. This paper reports on the initial sourcing attempt of Kuril Islands obsidian through the analysis of 131 obsidian artifacts. Data from this research were generated through the application of portable XRF technology, and are used to address research questions concerning prehistoric mobility, exchange, and social networking in the Kuril Islands.     

NON‐DESTRUCTIVE ANALYTIC METHOD USING XRF FOR DETERMINATION OF PROVENANCE OF ARCHAEOLOGICAL OBSIDIANS FROM THE MEDITERRANEAN AREA: A COMPARISON WITH TRADITIONAL XRF METHODS*

A non‐destructive analytical method using wavelength‐dispersive X‐ray fluorescence (WDXRF) that allows the establishment of the provenance of archaeological obsidians was developed and a comparison with the classical XRF method on powders is discussed. Representative obsidian samples of all the geological outcrops of archaeological interest of the Mediterranean area (Lipari, Pantelleria, Sardinia, Palmarola and the Greek islands of Melos and Gyali), were analysed with the normal procedures used in rock analysis by XRF (crushing, powdering and pelletizing). The non‐destructive XRF analysis was instead conducted on splinters taken from the original geological pieces, with the shape deliberately worked to be similar to the refuse usually found at archaeological sites. Since the analysis was conducted on the raw geological fragment, intensity ratios of the suitably selected chemical elements were used, instead of their absolute concentrations, to avoid surface effects due to the irregular shape. The comparison between concentration ratios (obtained by traditional XRF methods) and the intensity ratios of the selected trace elements (obtained from the non‐destructive methodology) show that the different domains of the chemical composition, corresponding to the geological obsidians of the source areas, are perfectly equivalent. In the same way, together with the geological splinters, complete archaeological obsidians, from Neolithic sites, may be analysed and their provenance may be determined. The proposed non‐destructive method uses the XRF method. Due to its sensitivity, low cost and high speed, it is surely an extremely valid instrument for the attribution of the provenance of the archaeological obsidian from Neolithic sites.     

Local recipes or distant commodities? Lead isotope and chemical compositional analysis of glaze paints from the Salinas pueblos,New Mexico

For nearly four hundred years, Pueblo potters in the Rio Grande Valley of New Mexico produced technologically innovative glaze-decorated bowls and exchanged them widely among different villages. While potential sources of lead ores used to make glaze paints are found throughout the Rio Grande Valley region, researchers have only recently begun to identify which ore sources potters exploited and to understand the social and economic factors underlying patterns of ore resource use. In this paper we use stable lead isotope and electron microprobe analysis of glaze paints on Rio Grande Glaze Ware made at two Salinas pueblos to identify ore sources and glaze recipes used by their potters. Despite some isotopic overlap of ore sources, the lead isotope data point to regular exploitation of ores from the Socorro area of the southern Rio Grande. Salinas potters apparently used other sources as well, and likely mixed ores from different sources. We also identify four local glaze recipes that appear to incorporate multiple ore sources, suggesting that Salinas potters obtained raw ores rather than finished glaze paints.     

Compositional study of bronze vessels from the Derveni tombs of central Macedonia of the fourth century bce using energy‐dispersive micro‐X‐ray fluorescence (EDμXRF) spectrometry

The chemical composition of 61 copper alloy vessels was studied non‐invasively by energy‐dispersive micro‐X‐ray fluorescence (EDμXRF) spectrometry. The vessels were found in five tombs (A, B, D, Z and H) at Derveni in central Macedonia, Greece, which belong to the cemetery of the ancient city of Lete. The tombs are dated to the last quarter of the fourth century bce . The opulence of the numerous grave offerings denotes the high social status of the deceased within Macedonian society. The material under study was divided into two main groups according to their appearance and use. The first group included 44 vessels with a golden appearance for use in banquets; the second group consisted of 17 dark vessels for domestic use. The aim of this research was to study the vessels' technology according to their chemical composition. Both golden and dark vessels consisted of a binary Cu‐Sn alloy and a slight amount of impurities (Fe, Ni, Zn, Pb, As, Co, Sb, Ag, Ti). It is probable that during construction the ancient metalsmiths were taking into account criteria such as the desired appearance, cost of metals, future use and physical properties such as resistance to corrosion. Banquet vessels had a consistent chemical composition in all their different parts compared with those for domestic use. The only chemical element used systemically for alloying purposes, except Sn, was Pb in order to improve the castability of the bases and handles of the vessels. The study provides additional information about the metalworking of bronzes in central Macedonia in the fourth century bce, as well as about the access Macedonian metalworkers had at the time to the raw materials for such use.     

The technology of Copper Age funerary pottery from Central Italy: An integrated study of compositional analyses and manufacturing traces

The paper focuses on ceramic vessels unearthed from Copper Age necropolises located in the area of the modern city of Rome and commonly attributed to the Rinaldone culture. The peculiar vessels' shapes, mainly associated with the consumption of beverages, their accuracy of manufacture and the very low impact of these ceramic morphologies in the coeval household assemblages lead to the study of such an apparently selected production through a multidisciplinary research. Petrographic analysis, X-ray fluorescence (XRF) and X-ray diffraction (XRD) integrated with the analysis of manufacturing traces and X-ray investigation suggest the transmission of technological choices, which remained unchanged over almost two millennia.     

Responses of South African Agate and Chalcedony When Heated Experimentally,and the Broader Implications for Heated Archaeological Minerals

Here we present a database of responses by South African agate and chalcedony to heat treatment. This will assist analyses of heated stone tools not only in South African archaeological sites, but wherever heated agate and chalcedony pieces were knapped. The minerals are abundant worldwide. To replicate potential heating methods during the Stone Age we placed some minerals in a wood fire, some under coals, and others were buried in sediments beneath fires. Thermal responses include lustrous flaked surfaces, pot lid fractures, semi-circular internal fractures, rough internal surfaces, and crazing. Aerobic heating is implied by pot lid fractures. To explain the thermal responses we analyzed the minerals using X-ray fluorescence, Raman spectroscopy, and carbon and sulfur analyses. Our chalcedony contains more water and impurities than agate, making it more vulnerable to thermal damage. Our method of combining field experiments with chemical analyses has global applications even though we expect that mineral components of agate and chalcedony will vary slightly in different parts of the world.     

The Evolution of Pottery Production During The Late Neolithic Period at Sialk On The Kashan Plain,Central Plateau of Iran

The prehistoric sherds recovered from the North Mound of Tepe Sialk were investigated using XRF, XRD and SEM/EDX analyses. These studies showed the occurrence of a gradual evolution in pottery‐making from the Sialk I to Sialk II periods, eventually leading to the production of bulk red pottery at the final phase of Sialk II. The relative similarity of compositions, homogeneous microstructures and the presence of high‐temperature phases demonstrated a high degree of specialization in the selection of raw materials and control of the firing temperature and atmosphere among the potters of Sialk in the sixth millennium bc , peaking at the final phase of Sialk II.     

Evidence of Soldering Technology on Pre‐Columbian Gold Pendants from Western and North‐Western Colombia

Microscopic examination and analysis (metallography, X‐radiography, SEM–EDS, pXRF and μ‐XRF) of a group of stylistically linked gold alloy pendants from western and north‐western Colombia confirms the use of a highly unusual manufacturing technique for the region. While the Darién pendants were made using lost‐wax casting by a diverse group of cultures from southern Colombia through Costa Rica, only one subset of pendants produced in the Gran‐Zenú region (the Caribbean lowlands of northern Colombia) and the Chocó region (the Pacific area of western Colombia) in the Early Period (ad 0–900) was found to be manufactured by hammering of gold sheet and fine wires followed by hard soldering of components to produce true filigree. Similarities in features between the stylistically related cast and hammered pendants suggest that the hammered pendants may have served as a prototype for the cast versions. Other possible instances of hard soldering in the region are also presented.