Tracing population mobility in the Aegean using isotope geochemistry: a first map of local biologically available Sr/Sr signatures

Strontium isotope ratio (⁸⁷Sr/⁸⁶Sr) analysis of archaeological human skeletal remains is an efficient method of investigating past population movement and residential mobility by determining probable geographical origins for the individuals examined. For this to be achieved, however, a map of biologically available ⁸⁷Sr/⁸⁶Sr signatures across the region investigated is needed. This paper presents a first such map for the Aegean, based on ⁸⁷Sr/⁸⁶Sr values recovered mainly from archaeological animal dental enamel and modern snail shells from sites largely distributed in the southern part of this region. Although not exhaustive, this comprehensive dataset of local biologically available ⁸⁷Sr/⁸⁶Sr signatures shows a marked difference between Mainland sites of the Pindos and Parnassos zones and the islands of south-eastern Aegean crossed by the Sub-Pelagonian zone (0.70808–0.70869), and sites in the central Cyclades and the north-eastern Aegean islands falling into the Attic-Cycladic metamorphic belt and the Vardar zone, respectively (0.70926–0.71187). Biologically available ⁸⁷Sr/⁸⁶Sr values from sites on central Euboea in the Pelagonian zone, south-eastern Attica and the western Cyclades in the Attic-Cycladic metamorphic belt, and on Crete in the Gavrovo zone are also relatively high (0.70853–0.70931), but lower than those recorded for the central Cyclades and the north-eastern Aegean.     

The Movement and Exchange of Dogs in the Prehistoric Caribbean: An Isotopic Investigation

This study explores the feasibility of using strontium isotope (⁸⁷Sr/⁸⁶Sr) analyses of enamel from domestic dogs (Canis familiaris) to investigate networks of exchange in the prehistoric Circum‐Caribbean. Dog teeth were obtained from burial and domestic contexts from two prehistoric sites (Anse à la Gourde and Morel) on Grande‐Terre, Guadeloupe (Lesser Antilles). Strontium isotope results were compared with local biosphere ⁸⁷Sr/⁸⁶Sr data at the scale of the site, island and archipelago. The isotope results indicate both local and nonlocal origins with three dogs (30%) identified as nonlocal (one from Anse à la Gourde and two from Morel). The variance in ⁸⁷Sr/⁸⁶Sr ratios of the nonlocal dog teeth is consistent with diverse multiple origins external to the island of Grande‐Terre but consistent with origins from other islands of the Lesser Antilles. The diverse origins of the nonlocal dog samples indicate that the prehistoric circulation of dogs occurred at multiple scales from regional to long distance. Significantly, the ⁸⁷Sr/⁸⁶Sr ratios of some of the dog teeth are comparable with values of nonlocal humans at Anse à la Gourde determined in previous studies. It is possible that these comparable ⁸⁷Sr/⁸⁶Sr ratios result from similar natal origins, for example if individuals were migrating to Guadeloupe with dogs. The results of this study contribute to an ongoing regional investigation of the economic, social and political roles of animals and animal remains and the multiscalar networks of prehistoric mobility and exchange in the Circum‐Caribbean region. Copyright © 2013 John Wiley & Sons, Ltd.     

Sr/Sr variability in Puerto Rico: geological complexity and the study of paleomobility

The temptation to use biogeochemical techniques to resolve issues of paleomigration is evident and well intentioned. Knowledge of radiogenic strontium isotope baselines in a region of interest is a sine qua non of such archaeological studies of paleomobility. Here, we present the first detailed study of baseline ⁸⁷Sr/⁸⁶Sr values for the island of Puerto Rico. The high degree of ⁸⁷Sr/⁸⁶Sr variability present in this corpus of modern Puerto Rican bedrock and terrestrial malacological samples (0.70406–0.70909) is a testament to the complex geology of that island. This diversity of ⁸⁷Sr/⁸⁶Sr values makes parsing issues of origin a difficult and highly contingent task. Given these complexities, regional studies seeking to assess paleomigration by such isotopic means should proceed with a great deal of caution.     

IN‐SITU ELEMENTAL AND Sr ISOTOPE INVESTIGATION OF HUMAN TOOTH ENAMEL BY LASER ABLATION‐(MC)‐ICP‐MS: SUCCESSES AND PITFALLS*

Trace element and Sr isotope data were obtained by laser ablation‐ and solution mode‐(MC)‐ICP‐MS analysis for tooth enamel from remains excavated at the New Kingdom period Egyptian colonial and Nubian cemetery site of Tombos (Sudan). Elemental abundances determined by both methods of ICP‐MS analysis yielded comparable values; however, ⁸⁷Sr/⁸⁶Sr values obtained by laser ablation were higher compared to their solution mode counterparts. This discrepancy is related to the production of a molecular interference—Ca + P + O (overlaps ⁸⁷Sr); hence the higher ⁸⁷Sr/⁸⁶Sr values recorded during ablation analyses. Laser ablation studies of enamel may provide relatively precise ⁸⁷Sr/⁸⁶Sr values rather quickly but cannot be used for accurately deciphering historical population migrations.     

87Sr/86Sr: a New Discriminant for Provenancing Neolithic Porcellanite Artifacts from Ireland

Antrim porcellanite (thermally metamorphosed Tertiary laterite) was the most common raw material used in the production of stone implements during the Neolithic in Ireland and was worked at two localities in North Antrim: Tievebulliagh, near Cushendall and Brockley on Rathlin Island.Attempts have been made to provenance material from these two known sources, the most successful to date being the use of geochemical data (Sr and Yppm). Here we present a new geochemical discriminant—Sr isotopic data—which reveal that Tievebulliagh and Brockley porcellanites are distinctive. Present-day⁸⁷Sr/⁸⁶Sr ratios form two discrete groupings ranging from 0·705894±25–0·706443±24 at Tievebulliagh and 0·704088±27–0·704587±25 at Brockley. A coherent relationship between⁸⁷Sr/⁸⁶Sr and Sr (ppm) reiterates the use of Sr content as a discriminant and illustrates the geochemical variability of Sr between these two sources.Although this is a destructive technique,⁸⁷Sr/⁸⁶Sr represents the best discriminant to date for Antrim porcellanites and will enable definitive provenancing of porcellanite artifacts from Ireland with important archaeological implications.     

Study on the strontium isotope standard in pig teeth excavated from Zaoshugounao site,Shaanxi Province of China

In archaeology, strontium isotope analysis is developing into an efficient scientific technique for tracing the movement of prehistoric humans and animals. Determining the local bioavailable ⁸⁷Sr/⁸⁶Sr ratio range is the key to distinguishing whether the human or animal is indigenous to the local area. It has been shown that the ⁸⁷Sr/⁸⁶Sr ratio in the enamel of pigs can be an excellent sample to determine the range of local strontium isotope ratio at the site. However, pigs may not be all local at the site, and there is no special study on whether pigs’ different ages and tooth types impact the local strontium isotope characteristics. In this paper, the tooth enamel of 19 pigs from the Zaoshugounao site for strontium isotope ratio (⁸⁷Sr/⁸⁶Sr) by multicollector–inductively coupled plasma mass spectrometry. There were no significant differences in ⁸⁷Sr/⁸⁶Sr ratios of local pigs at different months and different molar types, which did not affect the determination of the local strontium isotope standard. Based on the local strontium isotope ratio range (0.711056–0.711476), we found that five pigs were non-local. The Jing and Wei river basins (in Guanzhong basin) and northern Shaanxi are likely sources of non-pigs.     

Spatial variation of biologically available strontium isotopes (Sr/Sr) in an archipelagic setting: a case study from the Caribbean

This paper presents the results of strontium (Sr) isotope analysis of modern and archaeological animal remains and modern plant samples from the Caribbean region. The goal is to assess if patterns of human mobility can be determined from the archaeological record in an archipelagic setting. The range of variability and spatial distribution of biologically available strontium isotope signatures is reported and data evaluated to determine if sufficient heterogeneity exists to permit the identification of mobility despite the presence of potentially large contributions of marine strontium in island and coastal ecosystems. The (is)landscape is divided into several sub-regions based on the age and lithology of underlying geology and the variability of ⁸⁷Sr/⁸⁶Sr ratios is reported as; mean ⁸⁷Sr/⁸⁶Sr ± 2 standard deviations, number of samples: 1) Volcanic and Intrusive rocks (0.7077 ± 0.0019; n = 162); 2) Cretaceous–Miocene Limestone (0.7085 ± 0.0009; n = 50); 3) Pliocene–Quaternary Limestone (0.7091 ± 0.0004; n = 54); 4) Sedimentary Deposits (0.7094 ± 0.0015; n = 16); 5) Metamorphic Deposits (0.7104 ± 0.0014; n = 6). There are substantial differences between expected ⁸⁷Sr/⁸⁶Sr values based on associated geology and measured ⁸⁷Sr/⁸⁶Sr in flora and fauna samples. These differences emphasize the importance of focusing on bioavailable strontium, as opposed to geological proxies, for estimations of Sr isotope ranges, especially in archipelagic environments. While some overlap exists between the ⁸⁷Sr/⁸⁶Sr ranges of certain sub-regions, other sub-regions possessed limited variation and could be distinguished based on strontium isotope data. This spatial patterning of biologically available strontium indicates that strontium isotope analyses can be successfully applied to the archaeological study of human mobility within the Caribbean region.     

HUMAN MOBILITY AT THE EARLY NEOLITHIC SETTLEMENT OF VAIHINGEN,GERMANY: EVIDENCE FROM STRONTIUM ISOTOPE ANALYSIS*

As evidence concerning human mobility during the transition to agriculture in central Europe, we present the results of strontium isotope analysis of human skeletons from the Neolithic village of Vaihingen, Germany. We find significantly more ‘non‐local’⁸⁷Sr/⁸⁶Sr values from humans buried in a Neolithic ditch surrounding Vaihingen than from those buried within the settlement. These results fit with previous studies showing a correlation between burial circumstances and strontium isotope signatures from LBK cemeteries of southwestern Germany ( Price et al. 2001 ; Bentley et al. 2002 ). A pilot study of Neolithic animal teeth from Vaihingen suggests that either ‘local’⁸⁷Sr/⁸⁶Sr signatures were more variable than the analysed human bones suggest, or that these domestic animals themselves were mobile, perhaps ranged by mobile pastoralists.     

Revisiting the potential of carbonized grain to preserve biogenic 87Sr/86Sr signatures within the burial environment

Strontium (Sr) isotope analysis of archaeological crops is a potential method of provenancing and identifying the movement of crops in the past, but there remains uncertainty about whether original ⁸⁷Sr/⁸⁶Sr values can be obtained from carbonized buried grains. We have determined that hydrochloric acid (HCl) leaching removes some, but not all, exogenous Sr from carbonized cereal grains buried in soil for up to one year. We conclude that while further work could refine the leaching method, Sr isotope analysis of archaeological cereal grains can distinguish crops sourced from outside a particular (e.g., local) area if it can be shown that leaching moves grain ⁸⁷Sr/⁸⁶Sr values significantly away from the expected Sr signature.     

Identifying immigrants to Tikal,Guatemala: Defining local variability in strontium isotope ratios of human tooth enamel

Stable strontium isotopes have been used to identify the skeletons of migrants in several recent archaeological studies, in which local ⁸⁷Sr/⁸⁶Sr values have been inferred through statistical parameters of human ⁸⁷Sr/⁸⁶Sr data, or by reference to local fauna or other environmental samples. This paper compares these approaches using data from the ancient Maya city of Tikal, Guatemala. The skeletons of eight migrants from distant geological zones are readily apparent among the 83 Tikal skeletons sampled. Three additional non-local skeletons can be eliminated to obtain a normally distributed “local” Tikal sample. The mean of this sample is higher than the available data for local fauna and for lime that may have been used to treat maize at Tikal. It is possible that imported sea salt with a high ⁸⁷Sr/⁸⁶Sr ratio could account for this elevated mean for Tikal humans. Modeling demonstrates that dietary ⁸⁷Sr/⁸⁶Sr may be raised to the level found at Tikal by a daily intake of only 6 g of sea salt.     

Isotopic evidence for Middle Horizon to 16th century camelid herding in the Osmore Valley,Peru

Archaeological and zooarchaeological data indicate that camelid pastoralism was a subsistence and economic mainstay of Middle Horizon and more recent cultures in the Osmore region of southern Peru. However, it is not known whether camelids were primarily herded in highland puna pastures or near lower elevation sites in the middle valley or along the coast. This research examines the elevation of archaeological camelid herding in the Osmore Valley using stable isotope analysis. Stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope ratios were measured on 28 archaeological camelid bone samples from the Middle Horizon sites of Cerro Baúl and Cerro Mejía, the Late Intermediate site of Yaral and the late pre‐Hispanic to Colonial period site of Torata Alta. Twenty‐three archaeological camelids have δ¹³C and δ¹⁵N values similar to five modern camelids maintained in highland puna pastures. In contrast, three camelids from the high status Wari site of Cerro Baúl, and two from Yaral have unexpectedly high δ¹³C and/or δ¹⁵N values outside the expected range for camelids pastured in highland puna habitats. The results may be explained by differences in foddering practices, altitudinal herding range or climatic conditions. Strontium isotope ratios (⁸⁷Sr/⁸⁶Sr) were also assessed to infer pasture elevation using the camelid remains from Cerro Baúl (n = 11). One individual in this sub‐sample exhibits a non‐local ⁸⁷Sr/⁸⁶Sr value indicative of an origin in the highland puna region east or south of Lake Titicaca. It was not possible to further distinguish between camelids herded in lower to middle elevation habitats outside the Lake Titicaca basin using ⁸⁷Sr/⁸⁶Sr values. This study suggests that multiple isotope proxies may be used to identify animals primarily pastured in lowland coastal versus highland puna (> 4000 masl (meters above sea level)) habitats, but are less useful at distinguishing between animals pastured in lower to middle elevation settings. Copyright © 2010 John Wiley & Sons, Ltd.     

87Sr/86Sr sourcing of ponderosa pine used in Anasazi great house construction at Chaco Canyon,New Mexico

Previous analysis of ⁸⁷Sr/⁸⁶Sr ratios shows that 10th through 12th century Chaco Canyon was provisioned with plant materials that came from more than 75 km away. This includes (1) corn (Zea mays) grown on the eastern flanks of the Chuska Mountains and floodplain of the San Juan River to the west and north, and (2) spruce (Picea sp.) and fir (Abies sp.) beams from the crest of the Chuska and San Mateo Mountains to the west and south. Here, we extend ⁸⁷Sr/⁸⁶Sr analysis to ponderosa pine (Pinus ponderosa) prevalent in the architectural timber at three of the Chacoan great houses (Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo). Like the architectural spruce and fir, much of the ponderosa matches the ⁸⁷Sr/⁸⁶Sr ratios of living trees in the Chuska Mountains. Many of the architectural ponderosa, however, have similar ratios to living trees in the La Plata and San Juan Mountains to the north and Lobo Mesa/Hosta Butte to the south. There are no systematic patterns in spruce/fir or ponderosa provenance by great house or time, suggesting the use of stockpiles from a few preferred sources. The multiple and distant sources for food and timber, now based on hundreds of isotopic values from modern and archeological samples, confirm conventional wisdom about the geographic scope of the larger Chacoan system. The complexity of this procurement warns against simple generalizations based on just one species, a single class of botanical artifact, or a few isotopic values.     

Baseline data for Andean paleomobility research: a radiogenic strontium isotope study of modern Peruvian agricultural soils

While the use of radiogenic strontium isotope values to examine paleomobility is increasingly common in the Andes, and beyond, many questions about baseline variability remain. To better understand baseline radiogenic strontium isotope compositions in the Andes, we present new ⁸⁷Sr/⁸⁶Sr values from Peruvian soil samples. Modern soil samples were collected from agricultural fields from the following areas in central and southern Peru: Arequipa, Atico, Camaná, Chala, Cusco, Ica, Ilo, Lima, Mejía, Moquegua, Nazca, Ocoña, Palpa, Pisco, Puno, Tacna, and Yauca. Samples were partially dissolved to better approximate the bioavailable strontium. Radiogenic strontium isotope values from the partially dissolved soil samples range from ⁸⁷Sr/⁸⁶Sr?=?0.70202 to 0.71894 and, for all soil samples, have a mean of ⁸⁷Sr/⁸⁶Sr?=?0.70773?±?0.00166 (1σ, n?=?114). In general, the ⁸⁷Sr/⁸⁶Sr values measured for soil samples collected from modern agricultural fields reflect the expected ⁸⁷Sr/⁸⁶Sr values based on bedrock geology. Comparing our new soil data with published radiogenic strontium isotope data for bedrock, soil, water, and faunal samples provides constraints on the regions in the Andes that can, and cannot, be distinguished through radiogenic strontium isotope analysis.     

Reduced Population Variance in Strontium Isotope Ratios Informs Domesticated Turkey Use at Chaco Canyon,New Mexico,USA

Traditionally, strontium isotopes (⁸⁷Sr/⁸⁶Sr) have been used as a sourcing tool in numerous archaeological artifact classes. The research presented here demonstrates that ⁸⁷Sr/⁸⁶Sr_bioapatite ratios also can be used at a population level to investigate the presence of domesticated animals and methods of management. The proposed methodology combines ecology, isotope geochemistry, and behavioral ecology to assess the presence and nature of turkey (Meleagris gallopavo) domestication. This case study utilizes ⁸⁷Sr/⁸⁶Sr_bioapatite ratios from teeth and bones of archaeological turkey, deer (Odocoileus sp.), lagomorph (Lepus sp. and Sylvilagus sp.), and prairie dog (Cynomys sp.) from Chaco Canyon, NM, USA (ca. A.D. 800–1250). Wild deer and turkey from the southwestern USA have much larger home ranges and dispersal behaviors (measured in kilometers) when compared to lagomorphs and prairie dogs (measured in meters). Hunted deer and wild turkey from archaeological contexts at Chaco Canyon are expected to have a higher variance in their ⁸⁷Sr/⁸⁶Sr_bioapatite ratios, when compared to small range taxa (lagomorphs and prairie dogs). Contrary to this expectation, ⁸⁷Sr/⁸⁶Sr_bioapatite values of turkey bones from Chacoan assemblages have a much lower variance than deer and are similar to that of smaller mammals. The sampled turkey values show variability most similar to lagomorphs and prairie dogs, suggesting the turkeys from Chaco Canyon were consuming a uniform diet and/or were constrained within a limited home range, indicating at least proto-domestication. The population approach has wide applicability for evaluating the presence and nature of domestication when combined with paleoecology and behavioral ecology in a variety of animals and environments.     

Migration in the Nile Valley during the New Kingdom period: a preliminary strontium isotope study

The value of strontium isotope analysis in identifying immigrants at numerous archaeological sites and regional areas has been demonstrated by several researchers, usually by comparing ⁸⁷Sr/⁸⁶Sr values of human tooth enamel and/or bone with the local strontium isotope signature determined by faunal and environmental samples. This paper examines the feasibility of using ⁸⁷Sr/⁸⁶Sr ratios to investigate residential mobility in the Nile Valley region, specifically at the New Kingdom period (∼1050–1400 BC) archaeological site of Tombos (ancient Nubia). Archaeological and textual information regarding this period indicates that immigrant Egyptians and local native Nubians were likely interacting at this site during a period of Egyptian colonial occupation. The results of this study suggest that non-local individuals may be distinguished from locals using ⁸⁷Sr/⁸⁶Sr values and that colonial agents in the Tombos population were probably both local native Nubians and immigrants.     

Provenancing East Mediterranean cedar wood with the <Superscript>87</Superscript>Sr/<Superscript>86</Superscript>Sr strontium isotope ratio

⁸⁷Sr/⁸⁶Sr isotope ratios of cedar wood from forests in the East Mediterranean have been compiled in order to investigate the feasibility of provenancing archaeological cedar wood finds. Cedrus sp. forests furnished a great amount of wood in antiquity, for purposes ranging from ship to temple construction, and for fashioning cult statues and sarcophagi. The ⁸⁷Sr/⁸⁶Sr signatures of archaeological cedar samples may be compared with the preliminary dataset presented here to help determine the geographic origin of wooden artifacts. Sample sites include two forest areas in the Troodos Massif of Cyprus, five in the Lebanon, and two in Turkey’s Taurus Mountains. Sr ratios for wood varieties (i.e., early heartwood, late heartwood, sapwood, and twig wood) demonstrate relative uniformity between the xylem types frequently recovered from archaeological contexts. As such, this pilot study also assesses important issues of archaeological sampling and the geographical factors that influence Sr uptake in cedar trees of this region. While the regional signatures are distinct in most cases, small sample sizes and range overlap indicate the need for additional methods to make a case for a certain source forest. Alone, this method continues to be best used to disprove assumed wood provenances.     

Strontium isotopic characterization of the Palmottu hydrosystem (Finland): water–rock interaction and geochemistry of groundwaters

The Palmottu hydrosystem is located in a granitic host rock in southern Finland. Along well‐defined pathways in the fractured crystalline rock, strontium isotopes are used to trace the degree of water–rock interaction (WRI) and mixing processes in groundwaters. The ⁸⁷Sr/⁸⁶Sr ratios range between 0.716910 and 0.735606 in the surface waters and between 0.719991 and 0.750787 in the groundwaters, but are between 0.720 and 0.735 in most of the samples. Moreover, the results show a lack of correlation between the water chemistries determining the classification into different water‐types (Na–Cl, Na–SO₄, etc.) and the results of the strontium (Sr) contents and Sr isotopic ratios. From a WRI standpoint, this implies that the Sr behaviour is independent of the water chemistry; the occurrence of large ⁸⁷Sr/⁸⁶Sr variations is site specific and mainly dependent on the lithology. A model to determine the ⁸⁷Sr/⁸⁶Sr ratio of water after interaction with granite was developed. This model is based on the assumption that Sr was derived from three minerals: plagioclase, K‐feldspar and biotite. The results of the calculation indicate that around half of the water analysed within the Palmottu hydrosystem can be explained by the weathering of the granites. However, clearly lower ⁸⁷Sr/⁸⁶Sr are observed in waters when compared to the calculated ⁸⁷Sr/⁸⁶Sr and other sources of Sr, with low ⁸⁷Sr/⁸⁶Sr, rather than the calculated granite–water interaction, which may be suspected. When comparing the ⁸⁷Sr/⁸⁶Sr and ion ratios (Ca/Na, Mg/Na, Sr/Na, Cl/Na), the scattering of the data can be explained by the presence of four end‐members: a brine component (low ⁸⁷Sr/⁸⁶Sr and Ca/Na ratios…), a deep granitic component (high ⁸⁷Sr/⁸⁶Sr ratios and low Ca/Na ratios…), a subsurface component (intermediate ⁸⁷Sr/⁸⁶Sr ratios associated with high Ca/Na ratios…) and a surface end‐member:snow and river drainage (low ⁸⁷Sr/⁸⁶Sr and low Ca/Na ratios…). These extreme end‐members define a series of WRI‐mixing line within a rather complex hydrosystem.     

A strontium isotope analysis on the relationship between ritual tooth ablation and migration among the Jomon people in Japan

Distinct patterns can be discerned in the extensive ritual tooth ablation found among the human skeletal remains of the Late–Final Jomon period (ca. 3200–2800 cal BP) in Japan. Based on comparative observations of sex and grave patterns in the skeletal remains, two major patterns in ritual tooth ablation, termed type 4I and type 2C, have been assigned to locals and immigrants, respectively. In order to test this hypothesis, strontium (Sr) isotope (⁸⁷Sr/⁸⁶Sr) analyses were performed on human skeletal remains from the Yoshigo shell mound in Aichi Prefecture, central Japan. Plants in the surrounding area were also examined to illustrate the geographic ⁸⁷Sr/⁸⁶Sr distribution. The Sr isotopic variation in human tooth enamel (⁸⁷Sr/⁸⁶Sr = 0.70868–0.71028) was greater than that in human bones (⁸⁷Sr/⁸⁶Sr = 0.70871–0.70943). Individuals with higher Sr isotope ratios in their tooth enamel than seawater Sr values of 0.7092 can be identified as immigrants (36% of population). The presence of these isotopically identified immigrants between both type 2C and type 4I individuals does not support the previous hypothesis. The intra-population ⁸⁷Sr/⁸⁶Sr distribution of tooth enamel of type 2C individuals showed a significantly higher mean ratio than that of type 4I individuals, suggesting a higher proportion of immigrants among the former.     

PATTERNS OF IRON AGE HORSE SUPPLY: AN ANALYSIS OF STRONTIUM ISOTOPE RATIOS IN TEETH*

This paper presents a pilot study of strontium (Sr) isotope ratios from Iron Age horse tooth enamel samples. It compares ⁸⁷Sr/⁸⁶Sr ratios from horse teeth to estimates for local ranges of biologically available strontium, to investigate whether horses were being bred at the sites where their remains were discovered. A horse from Middle Iron Age Rooksdown, Hampshire, was not bred at the site but, rather, came from as far away as Wales, Scotland or continental Europe. Horse teeth from Middle Iron Age Bury Hill, Hampshire, returned ⁸⁷Sr/⁸⁶Sr values typical of local chalkland.     

Strontium Isotopes in the Investigation of Early Glass Production: Byzantine and Early Islamic Glass from the Near East*

⁸⁷Sr/⁸⁶Sr ratios have been determined for glasses from four production sites, dated to between the sixth and the 11th centuries, in the Eastern Mediterranean region. On the basis of elemental analyses, the glasses at each location are believed to have been melted from different raw materials. Two glass groups, from Bet Eli‘ezer and Bet She‘an, in Israel, are believed to have been based upon mixtures of Levantine coastal sands and natron, and have ⁸⁷Sr/⁸⁶Sr ratios close to 0.7090, plus high elemental strontium, confirming a high concentration of modern marine shell (⁸⁷Sr/⁸⁶Sr ~ 0.7092) in the raw materials. The isotopic compositions of these two groups of glasses differ slightly, however, probably reflecting a varying ratio of limestone to shell because the sands that were utilized were from different coastal locations. Natron‐based glasses from a workshop at Tel el Ashmunein, Middle Egypt, have ⁸⁷Sr/⁸⁶Sr values of 0.70794–0.70798, and low elemental strontium, consistent with the use of limestone or limestone‐rich sand in the batch. High‐magnesia glasses based on plant ash, from Banias, Israel, have ⁸⁷Sr/⁸⁶Sr values of 0.70772–0.70780, probably reflecting the isotopic composition of the soils that were parental to the plants that were ashed to make the glass. Strontium and its isotopes offer an approach to identifying both the raw materials and the origins of ancient glasses, and are a potentially powerful tool in their interpretation.