Obsidian Provenance Research Articles

MORE THAN JUST JEMEZ PUEBLO OBSIDIAN: COMMENT ON LIEBMANN'S “… LANDSCAPES OF SIGNIFICATION IN THE AMERICAN SOUTHWEST”

Liebmann's (2017) essay on the relationship between Jemez Pueblo and the Valles Caldera of northern New Mexico seems to imply that the Jemez Pueblo had an exclusive relationship with the caldera, particularly Redondo Peak, and the major obsidian source Cerro del Medio (CDM). This is curious given that abundant obsidian provenance studies from the region exhibit equal to or nearly equal proportions of Cerro del Medio obsidian that are not considered ancestral to Jemez Pueblo. Liebmann's regional perspective based on landscape theory appears flawed by a lack of regionally specific data.

Obsidian procurement and distribution in the Northwestern Maya lowlands during the Maya Classic, a regional perspective

A collection of 1338 obsidian artifacts and debitage from 37 archaeological sites (Early Formative to Late Classic) in the Northwestern Maya lowland in Mexico were analyzed using EDXRF and an attribute analysis. The study includes obsidian collected from urban population nodes like Chinikihá, Moral-Reforma, and Yaxchilán, incorporating the different types and size of settlements that include single platforms in the rural areas. The study illustrates a global perspective of the local communities in their daily use of obsidian. The application of an elemental sourcing analysis yielded the provenance of obsidian from sources in Guatemala (El Chayal, Ixtepeque, Jilotepeque) and Mexico (Zaragoza, Pachuca, Penjamo), pointing to the complex interregional and long-distance network of exchange that extended beyond the study area.

Inter-laboratory validation of the WDXRF, EDXRF, ICP–MS, NAA and PGAA analytical techniques and geochemical characterisation of obsidian sources in northeast Hokkaido Island, Japan

Obsidian provenance studies, based on geochemical signatures, are important for determining the source regions of obsidian artefacts. Such research depends on the availability of reproducible geochemical data. An inter-laboratory study was conducted to validate analytical methods applied to samples from four obsidian sources in northeast Hokkaido Island (Shirataki, Rubeshibe, and Oketo regions). The methods applied were Wavelength-Dispersive X-ray Fluorescence (WDXRF), Energy-Dispersive X-ray Fluorescence (EDXRF), Inductively Coupled Plasma–Mass Spectrometry (ICP–MS), Neutron Activation Analysis (NAA) and Prompt-Gamma Activation Analysis (PGAA). Eight laboratories in Japan, the Russian Federation, Republic Korea, Hungary, Canada, and the USA took part in the trials. Results indicate discrepancies between laboratories, but compositional data for 53 elements were successfully compiled, and reference compositions for 16 elements in each sample defined. Based on these data, a new chemical discrimination scheme is proposed for obsidian sources in the Shirataki, Rubeshibe, and Oketo regions. This scheme is applicable to the discrimination of obsidian sources using semi-quantitative EDXRF analysis, with this being important in non-destructive provenance studies of artefacts. This study fosters the further establishment of reference materials for obsidian sources in the Hokkaido region, and the sharing of such materials.

Application of non-destructive XRF method to the study of the provenance for archaeological obsidians from Italian, Central European and South American sites

This paper presents the results of the attribution of approximately 1700 artifacts, from Italian, Central European and South American sites to the geological obsidian sources. The provenance was determined using the non-destructive X-ray Fluorescence (XRF) analytical method, based on the secondary X-ray intensity proposed by Crisci et al. (1994) and optimized by De Francesco et al. (2008).In the first phase of the research, to test the non-destructive XRF method, the analysis on entire obsidian fragments (similar to archaeological waste) was initially carried out on 60 samples representative of all the geological outcrops in the Mediterranean region. The secondary X-ray intensities obtained by non-destructive XRF on whole pieces were compared with the results using the XRF method on powders, carried out on the same samples (major elements, and selected trace elements, such as Nb, Y, Zr, Rb and Sr) as exhaustively described in De Francesco et al. (2008). These five trace elements were sufficient to characterize (by both methods) the different places of obsidian origin, because they are particularly indicative of the genetic processes that produced obsidian.The provenance of the obsidian artifacts was determined by comparing the X-rays intensity ratios of the selected elements with those obtained on the entire fragments of the obsidian sources in the Mediterranean.The purpose of this paper is to show the results obtained in almost two decades of the application of the non-destructive XRF method. About 1700 archaeological obsidian fragments, from numerous Italian, Corsican, central European (Romanian) and South American (Central-western Argentina and Central Chile) archaeological sites, have been analyzed by non-destructive XRF, and assigned to obsidian sources. The provenance of 97% of the obsidian artifacts was successfully determined.The results demonstrate that the non-destructive XRF method - thanks to its sensitivity, low cost, and high speed - is an extremely valuable tool for the attribution of the provenance of archaeological obsidian in the areas under consideration.

Reassessment of WD-XRF method for obsidian provenance shareable databases

The X-ray fluorescence technique using peak intensity ratios of trace elements is one of the faster, less expensive and less invasive methods for obsidian sourcing. Moreover, XRF peak intensity ratios are particularly useful when the artifact is slightly altered, particularly affecting the alkali cations, or when its surfaces are covered with a fine film of carbonate deposits formed while the sample was buried.The limitation of this technique results from the dimensions of the obsidian samples: very small obsidian samples, nowadays about 1 cm in size, are difficult to measure given the very few X-rays emitted by their surface.An aluminium holder closed with a very thin Mylar© polyester film was prepared and the specimen, positioned at the centre of the surface of the Mylar film, was placed in the XRF spectrometer. The use of recent technology XRF apparatus equipped with a 4 kW Rh anode X-ray tube coupled with an accurate measurement of refined X-ray characteristic lines, that exclude the X-ray background contribution, of five trace elements (Rb, Sr, Y, Zr, Nb), made it possible to determine the source geological outcrop of archaeological obsidian samples as little as 7 mm and as light as 40 mg.A database of peak intensity ratios, background and interference free, of five trace elements was produced for obsidian samples from Monte Arci, Palmarola, Lipari, Pantelleria, Gyali and Melos.This database may be used by other laboratories provided the X-ray intensity of the trace elements Rb, Sr, Y, Zr, Nb are measured as net intensities, that is purified from the contribution of the background and from interelemental interferences.A comparison between data obtained with two spectrometers, of different generation and differently calibrated, confirmed the possibility of obtaining a database that can be shared with other laboratories.The proposed XRF method was tested on Neolithic obsidians from four Apulian sites (Ripa Tetta at Lucera, Palestra ex G.I.L. at Foggia, Pulo di Molfetta and Grotta di Santa Barbara at Polignano a Mare), whose source outcrops had been also determined by SEM-EDS.

Investigating the provenance of obsidian from Neolithic and Chalcolithic sites in Bulgaria

Portable energy-dispersive X-ray fluorescence (pXRF) has become a widely used tool for the chemical characterisation (source identification) of obsidian found in archaeological contexts. While laboratory techniques such as neutron activation analysis (NAA) and inductively coupled plasma mass spectrometry (ICP-MS) can analyse more elements and have lower detection limits, pXRF can provide quantitative data of sufficient resolution to be able to match obsidian artefacts with their volcanic sources. At the same time, pXRF offers several advantages for obsidian research: (i) it can be deployed ‘in the field’ (i.e. on site or in a museum) without the need to bring samples back to a laboratory for analysis; (ii) information on elemental composition can be obtained relatively quickly; and (iii) measurements require no special preparation of samples and cause no visible damage to materials.

A Reassessment of Archaeological Obsidian from Southern Alta California and Northern Baja California

This article offers a reassessment of the sources of archaeological obsidian found in southern California and northern Baja California based on new information regarding the geological availability of obsidian in Baja California, Mexico. In particular, we demonstrate that a previously unknown obsidian chemical group, referred to here as Tinajas obsidian, was for decades misidentified as San Felipe obsidian in regional archaeological analyses. In light of new data derived from geological surveys, geochemical analyses, and regional archaeological research, previous obsidian provenance reports from both sides of the border are reviewed. Our findings indicate that the archaeological distribution of the Tinajas obsidian group extends throughout northern Baja California and into southern California. In contrast, San Felipe obsidian appears to have had a more restricted geographical distribution than previously thought.

Long-distance provenance for obsidian artifacts of Mesoamerica Preclassic and Early Classic periods found in the Los Naranjos Archaeological Park (Honduras)

Los Naranjos is one of the most important pre-Columbian human settlements of Honduras related to the south-easternmost border of the Mayan civilization. Although the archaeological site mostly spans from 850 BC to 1250 AD, the present obsidian study was only focused on the Preclassic and Early Classic periods (Jaral, 800–400 BC and Eden, 400 BC–550 AD) where undamaged blades and/or retouched obsidian flakes are rare. In this way, the INAA analyses of 17 obsidian samples, compared with major-trace elements data of Honduran and Guatemalan obsidian sources, are mostly representative of waste flakes. Lithic artifacts of Los Naranjos such as sandstones, basalts, and quartzites come from local geological outcrops; whereas, obsidian provenance has to be searched from sources which are located within a radius up to 300 km far away. San Luis, La Esperanza, and Guinope obsidian sources are located in Honduras while the three most exploited Highland Guatemalan obsidian outcrops, which have been dominating long-distance trade in the Maya area mostly for the Classic-Postclassic periods, are San Martin de Jilotepeque, El Chayal, and Ixtepeque. An Ixtepeque provenance, for all the investigated obsidian samples of Preclassic and Early Classic periods found in the Los Naranjos Archaeological Park, was established, thus emphasizing a long-distance source (180 km). This also confirms that Ixtepeque represents the most important provenance of the obsidian artifacts found in archaeological sites of Western and Central-Western Honduras. The possible role played by some of the most important rivers of Guatemala and Honduras as waterway networks of transport was finally pointed out. New INAA chemical data from the Honduran obsidian source of La Esperanza (“Los Hoyos”, 4 samples) are also reported in this paper.

Human responses to climate change on obsidian source exploitation during the Upper Paleolithic in the Central Highlands, central Japan

Upper Paleolithic hunter-gatherers intensively exploited obsidian sources 1200–2000 m a.s.l. in the Central Highlands, central Japan. Previous studies have suggested that the last glacial maximum (LGM) decreased human obsidian procurement in the source area because of its high altitude. However, the relationship between the impacts of the LGM and human responses in the source area based on convincing evidence from the paleoclimate, obsidian provenance data, and archaeology remains poorly understood. This study examines the correlations among pollen record datasets during the past 30,000 years from the Central Highlands 1400 m a.s.l.; more than 85,000 pieces of obsidian provenance data for the Chubu-Kanto region; and chronological sequences of Upper Paleolithic industries in the Central Highlands. Through synthetic analysis, we reconstruct historical changes in the human–environment interaction in the Central Highlands during the Upper Paleolithic. Our combined data shows the early LGM constraining the procurement activity at the sources; an increase in active human responses to the LGM cold phase; and changes in the land use of the source area in the terminal LGM triggered by the appearance of new lithic technology and the reorganization of mobility ranges. We find that human adaptations to the LGM conditions related to the natural resource exploitation around a latitude of 36°N were complex.

Obsidian as a commodity to investigate human migrations in the Upper Paleolithic, Neolithic, and Paleometal of Northeast Asia

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.

Evaluating the applicability of portable-XRF for the characterization of Hokkaido Obsidian sources: a comparison with INAA, ICP-MS and EPMA

As a result of the limited application of portable X-ray fluorescence (pXRF) in archaeological research in Japan it is necessary to compare this technique to proven, laboratory-based, analytical techniques. In this study instrumental neutron activation analysis, inductively-coupled plasma mass spectrometry, and electron probe microanalysis are used to validate pXRF and determine the overall suitability of this technique for archaeological obsidian provenance studies in Hokkaido, northern Japan. Furthermore, the results of this study are compared to previously published data to assess reproducibility and compatibility. This study demonstrates the reliability of pXRF for the rapid characterization of Hokkaido obsidian while contributing to the ongoing evaluation of the applicability of “off-the-shelf” pXRF to obsidian provenance research in archaeology.

Identifying the Ethiopian origin of the obsidian found in Upper Egypt (Naqada period) and the most likely exchange routes*

The absence of obsidian sources in Egypt implies that obsidian excavated in fourth-millennium bc Upper Egyptian sites arrived in Egypt over long distances. This article develops an obsidian provenance study, based on chemical composition that permits to determine that obsidian found in Egypt came from neither Anatolia nor the Arabian Peninsula. Egyptian obsidian has a compositions similar to that from the Porc Epic cave in the Ethiopian Rift Valley. Considering the evolution of East African Paleolithic and Neolithic source-site distances, the most likely sources were less than 250 km away from the Porc Epic cave. The results of the study permit to suggest that terrestrial and/or Nilotic exchange routes were more likely than maritime routes involving the Red Sea and the coasts of Eritrea and the Arabian Peninsula. The ‘down-the-line’ exchange model would incorporate the Gash Delta and the Nubian A-Group.

Prompt Gamma Activation Analysis of the Nyírlugos obsidian core depot find

The Nyirlugos obsidian core depot find is one of the most important lithic assemblages in the collection of the Hungarian National Museum (HNM). The original set comprised 12 giant obsidian cores, of which 11 are currently on the permanent archaeological exhibition of the HNM. One of the cores is known to be in Debrecen. The first publication attributed the hoard, on the strength of giant (flint) blades known from the Early and Middle Copper Age Tiszapolgar and Bodrogkeresztur cultures, to the Copper Age. In the light of recent finds it is more likely to belong to the Middle Neolithic period. The source area was defined as Tokaj Mts., about 100 km to the NW from Nyirlugos. The size and beauty of the exceptional pieces exclude any invasive analysis. Using Prompt Gamma Activation Analysis (PGAA), we can measure major chemical components and some key trace elements of stone artefacts with adequate accuracy to successfully determine provenance of obsidian. Recent methodological development also facilitated the study of relatively large objects like the Nyirlugos cores. The cores were individually measured by PGAA. The results show that the cores originate from the Carpathian 1 sources, most probably the Vinicky variety (C1b). The study of the hoard as a batch is an important contribution to the assessment of prehistoric trade and allows us to reconsider the so-called Carpathian, especially Carpathian 1 (Slovakian) sources.

Obsidian provenance determination using the beam stability controlled BSC-XRF and the PIXE-alpha portable spectrometers of the LANDIS laboratory: the case of the Via Capuana settlement in Licodia Eubea (Sicily)

In the last decade about 800 obsidian artifacts coming from various archaeological sites of Sicily have been analyzed using the BSC-XRF (beam stability controlled-x-ray fluorescence) and PIXE-alpha (particle induced x-ray emission, using low-energy alpha particles) portable spectrometers developed at the Landis laboratory of the LNS?INFN and IBAM?CNR in Catania (Italy). The portable BSC-XRF system allows the non-destructive analysis of Rb, Sr, Y, Zr and Nb trace concentrations, which are considered to be characteristic of the obsidian samples and consequently are indicative of the provenance quarries. Quantitative data on the above trace-element concentrations were deduced using a method that makes use of a multi-parameter linear regression. The portable PIXE-alpha spectrometer allows the quantitative determination of the matrix major elements, from Na to Zn. In this paper the updated versions of the instrumental devices and methods are presented together with a review of all the obtained data from various Sicilian sites. Results on compositional data for trace elements and major elements allowed us to identify Lipari and Pantelleria islands as the only two sources of the analyzed samples. Recent data about the Via Capuana settlement in Licodia Eubea are also presented and discussed for the first time.

Safety issues in cultural heritage management and critical infrastructures management

Safety issues in cultural heritage management and critical infrastructures management

Determining the Provenance of Obsidian in Southern Patagonia Using Optical Properties

This paper aims to evaluate the optical properties of natural rhyolite obsidians that might be useful in the identification of different sources of archaeological samples. Even though colour, degree of alteration, crystaloclast composition and texture are important properties by which sources can be identified, all of these features do not always lead to an unambiguous distinction. In this regard, the refractive index (ND) becomes a helpful tool because it is not only sensitive to the chemical composition of natural glasses but also to their different thermal histories. Obsidians from six localities of Patagonia were analysed. Their refractive index measurements (ND) only range between 1.47 and 1.49, but the ND values of some of these sources are sufficiently constrained to allow discrimination between them.

AN ASSESSMENT OF THE CURRENT APPLICATIONS AND FUTURE DIRECTIONS OF OBSIDIAN SOURCING STUDIES IN ARCHAEOLOGICAL RESEARCH*

This paper thematically characterizes a large body of recent obsidian sourcing discourse as a means of highlighting the current place of obsidian provenance studies in larger archaeological discourse. It is shown that the field of obsidian sourcing is flourishing, with a clear upward trend in the number of published studies in the past decade. This paper further argues that sourcing is a means to an end, a way to determine where artefacts originate, and thus a means of addressing broader archaeological problems. Through this contextual framework, obsidian sourcing studies—and indeed all provenance studies—are seen as relevant because they transcend the increasingly specialized world of archaeological discourse.

Obsidian provenance for prehistoric complexes in the Amur River basin (Russian Far East)

The sources of high quality volcanic glass (obsidian) for archaeological complexes in the Amur River basin of the Russian Far East have been established, based on geochemical analyses by neutron activation and X-ray fluorescence of both ‘geological’ (primary sources) and ‘archaeological’ (artifacts from the Neolithic and Early Iron Age cultural complexes) specimens. A major obsidian source identified as the Obluchie Plateau, located in the middle course of the Amur River, was found to be responsible for supplying the entire middle and lower parts of the Amur River basin during prehistory. The source has been carefully studied and sampled for the first time. Minor use of three other sources was established for the lower part of the Amur River basin. Obsidian from the Basaltic Plateau source, located in the neighboring Primorye (Maritime) Province, was found at two sites of the Initial Neolithic (dated to ca. 11,000–12,500 BP). At two other sites from the same time period, obsidian from a still unknown source called “Samarga” was established. At the Suchu Island site of the Early Neolithic (dated to ca. 7200–8600 BP), obsidian from the ‘remote’ source of Shirataki (Shirataki-A sub-source) on Hokkaido Island (Japan) was identified. The range of obsidian transport in the Amur River basin was from 50 to 750 km within the basin, and from 550 to 850 km in relation to the ‘remote’ sources at the Basaltic Plateau and Shirataki-A located outside the Amur River valley. The long-distance transport/exchange of obsidian in the Amur River basin in prehistory has now been securely established.

New data and provenance of obsidian blocks from Middle Neolithic contexts on Corsica (western Mediterranean)

The provenance of twelve un-worked blocks and one part-knapped block recovered from the surface of five Middle Neolithic sites in the vicinity of Porto Vecchio, southeastern Corsica (western Mediterranean), was determined by ion beam analysis (PIXE). This is the first such discovery on Corsica of actual raw blocks of this exotic material. Twelve of these samples come from sources associated with the Monte Arci volcanic complex of Central-West Sardinia, with six each of the SA and SC chemical types. The only possible origin for the remaining block is Lipari, a raw material previously only attested by three artifacts from a Neolithic site of NW Corsica. This piece is aberrant for its unusual facies and its poor quality, making it quite unsuitable for knapping, and by extent distinct from the high quality glassy obsidian from Lipari that was used regularly by Neolithic peoples. This raises the question of the archaeological significance of this surface find.

The use of SEM-EDS, PIXE and EDXRF for obsidian provenance studies in the Near East: a case study from Neolithic Çatalhöyük (central Anatolia)

In this paper we evaluate the relative analytical capabilities of SEM-EDS, PIXE and EDXRF for characterizing archaeologically significant Anatolian obsidians on the basis of their elemental compositions. The study involves 54 geological samples from various sources, together with an archaeological case study involving 100 artifacts from Neolithic Çatalhöyük (central Anatolia). With each technique the artifacts formed two compositional groups that correlated with the East Göllü Dağ and Nenezi Dağ sources. The non-destructive capabilities of these methods are emphasized (albeit with certain analytical limitations in the case of SEM-EDS), suggesting important new techniques for Near Eastern obsidian provenance studies.