INDUCTIVELY COUPLED PLASMA-MASS SPECTROMETRY FOR THE ANALYSIS OF ANCIENT METALS*

Inductively coupled plasma-mass spectrometry (ICP-MS) is a relatively new analytical technique, growing in popularity, that offers many advantages over previously available instrumentation for the measurement of both the elemental and isotopic composition of metallic antiquities. The application of this method of analysis to archaeological metalwork is discussed and the technique compared with other methods of analysis commonly used in archaeometallurgy. Particular attention is drawn to the potential pitfalls and difficulties associated with ICP-MS and the need for extremely careful sample preparation and instrument operation.     

Monitoring the burial environment of terrestrial wet archaeological sites in The Netherlands

Abstract

Monitoring the burial environment of archaeological sites is necessary to assess the success of their preservation in situ. Also, monitoring the state of preservation of actual archaeological remains together with that of their burial environment will further our understanding of the degradation processes acting on archaeological remains in situ. These remains consist not only of objects made from wood, metal, stone, etc., but also of pollen, soil features and even micromorphological features. Although, to date, the precise degradation mechanisms of archaeological remains in situ are not yet fully understood, general agreement exists on which parameters should be monitored in wet terrestrial environments. Also, it has been established that in situ measurements are preferable to laboratory analyses of soil (water) samples. In practice, it is difficult to find suitable monitoring equipment for in situ measurement as it must meet many requirements: an in situ measuring principle; stable for a period of at least several months; robust for use in the field; and equipped with a datalogger. A suitable principle exists for measuring the redox potential, however a simple, robust field instrument with datalogger is not yet available. Monitoring of the water table level, temperature and oxygen content is possible with recently developed, commercially available instruments. Monitoring of acidity is less complex as it does not vary as rapidly as, for example, the redox potential; however, the recommended method is still based on analysing soil samples, which is not acceptable in the long term at archaeological sites.     

The Ben Lawers Historic Landscape Project: Simultaneous Multi-element Analysis of Former Settlement and Arable Soils by X-ray Fluorescence Spectrometry

X-ray fluorescence spectrometry (XRFS) was used in the analysis of A horizon soil samples collected from a former farming settlement and its associated area of infield (i.e. arable) located in the Central Highlands of Scotland. To date, XRFS has not been extensively used in geoarchaeological research, but in our study the simultaneous multi-element capabilities of this instrumental technique allowed the total concentrations of 25 major, minor, and trace elements to be fully quantified with acceptable levels of accuracy and precision. Included within this group of chemical elements are a number (e.g. Ba, Ca, P, Pb, Sr and Zn) that have proved to be of value to archaeological interpretation in earlier investigations undertaken in Scotland. In our preliminary work documented here, significant differences were found between the A horizon soils of former settlement and infield areas for 18 chemical elements. Subjecting the XRFS data—and three other measured variables: soil organic carbon (SOC), pH and A horizon depth—to discriminant analysis indicates that soils of former settlement and arable farming can be effectively classified according to their pH, SOC content and Ca, Cu, Mg, Rb, and Zn concentrations. The inference is that areas of former infield and settlement elsewhere at this study location in the Central Highlands may be able to be identified according to their soil chemical composition and use of discriminant function, even though the surface remains of pre-eighteenth century settlement sites are not readily evident today because they were constructed of perishable materials.     

THE TRADING OF ANCIENT GLASS BEADS: NEW ANALYTICAL DATA FROM SOUTH ASIAN AND EAST AFRICAN SODA–ALUMINA GLASS BEADS*

The occurrence of similar glass beads at archaeological sites in Africa and Asia bears witness to the trade relationship between the two continents. This paper reports elemental analysis results from a recent in‐depth laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) study of a group of archaeological glass beads with a specific alumina‐rich composition from East Africa, India and Sri Lanka. Based on the concentrations of the trace elements, two different subgroups were identified. One subgroup occurs at early periods (fourth century bce to fifth century ace ) in South India and Sri Lanka. The second subgroup appears at later dates in Africa and was identified at different Kenyan sites dated from the ninth to the 19th century ace , and at the contemporaneous site of Chaul in western India.     

Ethnoarchaeological analysis of Arctic fish processing: chemical characterization of soils on Nelson Island,Alaska

Activity area analysis of archaeological soils using multi-element characterizations can illuminate how subsistence operations are organized and how subsistence behavior has changed over time, and is increasingly common at archaeological sites. However, in many regions it is impossible to examine the elemental signatures in known anthropogenic soil samples in order to compare them with unknown archaeological samples. This ethnoarchaeological study examines the chemical composition of the soils at known fish processing areas in the contemporary community of Tununak on Nelson Island, western Alaska. Using a quadrupole inductively coupled plasma mass spectrometer (Q-ICP-MS), the concentrations of the following elements in the soil extract were recorded in parts per million (ppm): aluminum (Al), barium (Ba), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), phosphorus (P), strontium (Sr), titanium (Ti), and zinc (Zn). Fish processing area features are elevated in various elements, including sodium, magnesium, phosphorus, potassium, and manganese, and Ba/Sr, Ba/Ca, and Sr/Ca are also useful in distinguishing between fish processing areas and offsite areas.     

New Statistical Approaches to Intra‐individual Isotopic Analysis and Modelling of Birth Seasonality in Studies of Herd Animals

This paper introduces improved methods for statistically assessing birth seasonality and intra‐annual variation in δ¹⁸O from faunal tooth enamel. The first method estimates input parameters for use with a previously developed parametric approach by C. Tornero et al. The second method uses a non‐parametric clustering procedure to group individuals with similar time‐series data and estimate birth seasonality. This method was successful in analysing data from a modern sample with known season of birth, as well as two heterogeneous archaeological data sets. Modelling indicates that the non‐parametric approach estimates birth seasonality more successfully than the parametric method when less of the tooth row is preserved. The new approach offers a high level of statistical rigour and flexibility in dealing with the time‐series data produced through intra‐individual sampling in isotopic analysis.     

NEUTRON RESONANCE CAPTURE ANALYSIS OF SOME GENUINE AND FAKE ETRUSCAN COPPER ALLOY STATUETTES*

The probability of nuclei capturing neutrons reveals sharp peaks, so‐called ‘resonances’, which occur at neutron energies that are specific for each element. These resonances are very suitable for analysing the elemental composition of objects. They are the basis of a new analytical method, ‘neutron resonance capture analysis’ (NRCA). This is a fully non‐destructive method, which is applicable to almost all stable isotopes, determines the bulk elemental composition, does not require any sample preparation and results in a negligible residual activity. Recently, NRCA has been applied in a study of a series of bronze statuettes, obtained from the National Museum of Antiquity in Leiden (NL).     

ceraDAT—PROTOTYPE OF A WEB‐BASED RELATIONAL DATABASE FOR ARCHAEOLOGICAL CERAMICS

The prototype of a relational database for archaeological ceramics is presented. At this stage, the ceraDAT database contains the elemental compositions of several thousand ceramic artefacts from the Eastern Mediterranean, analysed by neutron activation analysis (NAA) at different laboratories. The data have been calibrated on the basis of the analytical routine and can be accessed via a web application. Apart from the elemental compositions, the database contains reference patterns of specific sites, metadata concerning archaeological information, the geographical distribution, literature references and former statistical evaluations. Due to the database design, the structure can be extended in future towards petrographical and mineralogical information.     

Deciphering the inorganic chemical record of ancient human activity using ICP-MS: a reconnaissance study of late Classic soil floors at Cancuén,Guatemala

Inorganic chemical analysis of soil floors using inductively coupled plasma-mass spectrometry (ICP-MS) was undertaken to provide information on the nature and location of past human activity in the ancient Maya city of Cancuén, Guatemala. The use of ICP-MS to detect trace and ultra-trace elemental enrichment of two excavated soil floors from the late Classic period is the first study of its kind in Mesoamerican archaeology. Geochemical background of the site was established by the analysis of palaeosols and nearby undisturbed ‘off-site’ soil profiles. Robust statistical methods used in the study clearly distinguished the level of anthropogenic enrichment across the former floors. Many elements measured showed only minor departures (10–20%) from the site's background soil chemistry. The greatest levels of elemental enrichment were detected in the rare earth elements, mercury, and gold. The latter is of particular interest considering the consensus that gold was absent from the world of the Classic-period Maya. Comparisons of the spatial pattern of mercury enrichment with lithic and archaeological data show strong linkages to past industrial and ritual activities. Elevated rare earth element concentrations were recorded broadly across both soil floors and are considered to be related to concentrated human occupation in antiquity.     

REPRODUCIBILITY OF ELEMENTAL ANALYSES OF BASALTIC STONE ARTEFACTS BY QUADRUPLE ICP–MS USING DIFFERENT SAMPLE SIZES AND DIGESTION METHODS,WITH IMPLICATIONS FOR ARCHAEOLOGICAL RESEARCH

Using high‐precision inductively coupled plasma mass spectrometry (ICP–MS), we measured >40 elements in basalts sampled by diamond micro‐drills to evaluate the effectiveness of different digestion methods and the reproducibility of elemental analysis for different sample sizes from 5 mg to 100 mg. The results indicate that those elements that are most suitable for geochemical characterization, such as rare earth elements (REE), high‐field strength elements (HFSE) and certain mobile elements (Rb, Sr, Th, U), show excellent reproducibility with an average relative standard deviation (RSD) of 3% between open‐beaker and pressured ‘bomb’ digestion methods. This observation rules out the presence of refractory phases such as zircon, which can only dissolve in pressured ‘bombs’, and suggests that the results from open‐beaker digestion are reliable. The ICP–MS data for powders of different weights ranging from 10 to 100 mg collected from two fine‐grained basalt artefacts display excellent reproducibility, with a RSD of <5% for the most important elements. The reproducibility is reduced when including the 5 mg weight fraction (RSD of ～2–9%), which is still sufficient for archaeological applications. Our results demonstrate the usefulness of 10 mg samples for elemental measurement, which is valuable for geochemical characterization and sourcing of fine‐grained basalt artefacts from museum collections that require minimal destructive sampling.     

COMPOSITION AND ORIGIN OF IAPYGIAN POTTERY FROM ROCA VECCHIA,ITALY

We have studied 35 samples of fragments of ceramic containers dated between the eleventh and the eighth centuries BC, found at the archaeological site of Roca Vecchia, some 20 km from Lecce along the Adriatic (Salentine) coastline. Analysis of the elemental composition of the finds has been performed by means of atomic emission spectroscopy in plasma and the results obtained have been treated with diverse multivariate statistical techniques. Except for some minor differences, the statistical analysis confirms the grouping structures indicated by typological and stylistic evaluations of the samples, in accordance with the validity of the above methods.     

The possible influence of post-harvest objectives on Cucurbita maxima subspecies maxima and subspecies andreana evolution under cultivation at the Argentinean Northwest: an archaeological example

This paper investigates the possible links between postharvest activities and methods of plant husbandry or management of Cucurbita maxima ssp. maxima and C. maxima ssp. andreana in the prehispanic Argentinean Northwest area. Microscopic methods were used to assess the micromorphological characteristics of modern specimens of South American Cucurbita and Lagenaria species to obtain diagnostic anatomical traits. These traits were then used as criteria for identifying archaeological Cucurbitaceae rind remains from domestic to funerary contexts of the Pampa Grande archaeological site (1720 ± 50 bp, cal. 259–433 ad). Following the taxonomic identification of the archaeological plant remains, they were futher assessed for signs of human selection or possible cultivation, including: rind thickness, qualitative characters (lobbing, wartiness and colour) and postharvest traits (artificial shape, charring, staining and decoration of sherds). The results indicate the presence of Lagenaria siceraria together with spontaneous, intermediate and domestic C. maxima morphotypes. Different subspecies maxima morphtypes were recognized: those intended as food, having thin pericarps to facilitate consumption and those intended also as food, but as containers too, as in Lagenaria, in which the rinds are thickened and lignified. The latter morphotype may possibly represent a strategy of postharvest intensification, but not through new processing techniques, but through the development of landraces with a longer fruit shelf life, resulting from changing husbandry criteria to selective pressures over cultivated stands.     

LEAD ISOTOPE RATIOS AS A MEANS OF SOURCING ANTHROPOGENIC LEAD IN ARCHAEOLOGICAL SOILS: A PILOT STUDY OF AN ABANDONED SHETLAND CROFT*

Results from soil chemical analysis have demonstrated enhanced concentrations of lead (Pb) associated with archaeological sites. However, interpretation of these Pb concentrations is difficult because of the multitude of possible Pb sources. This pilot study of an abandoned croft in Shetland suggests that Pb isotope ratios have the potential to identify sources of anthropogenic Pb. The results highlight two different Pb associations. The first includes hearth, house floor and house overburden soils, with end members of fuel materials and an unidentified material with a low (< 1.126) ²⁰⁶ Pb/ ²⁰⁷ Pb ratio. The second includes byre, kailyard (garden) and arable soils, with end members of hearth materials and local wind‐blown sand.     

An experimental ethnoarchaeological approach to understanding the development of use wear associated with the processing of river cane for split-cane technology

Southeastern Indians have been using cane (Arundinaria spp.) for basketry and matting for thousands of years. Unfortunately, it is only under extraordinary preservation conditions that such items survive archaeologically. Inferring the production of split-cane technology requires an understanding of prehistoric manufacturing and processing techniques. It is hypothesized that stone tools were once used to process cane for use in split-cane technologies. In the Southeast, it is not uncommon to find stone tools with traces of plant use; however attributing wear to specific plants has been problematic. Pilot experiments, grounded on ethnoarchaeological observations, were conducted with river cane (Arundinaria gigantea) in collaboration with expert basket weavers in the Cherokee Nation. The experimental ethnoarchaeological program was designed to test the efficiency of stone tools in cane processing and document use wear through microscopic observations. The results found that non-retouched flakes were efficient for processing river cane and that the different stages of splint preparation resulted in the differential development of use-related wear. Additional experimentation with river cane is necessary to better define use wear and establish criteria for identification in archaeological contexts. Nonetheless, the collaborative and experimental approach undertaken demonstrated the utility of combining traditional archaeological methods with experimentation, ethnoarchaeology, and tribal knowledge.     

Estimation of Age,Growth and Fishing Season of a Palaeolithic Population of Grayling (Thymallus thymallus) Using Scale Analysis

The fish remains sampled from archaeological sites are generally the result of human food refuse; therefore, the study of retrieved fish scales may provide reliable information on the season of capture and on paleoclimate and paleoenvironmental changes. Among Western European freshwater fishes, the grayling, Thymallus thymallus ¸ has the most easily recognizable scales and is a commonly recovered species from Palaeolithic contexts. This study, therefore, is based on the growth pattern analysis of modern and archaeological scales from grayling specimens. The modern specimens were collected monthly in France (n  = 22), Switzerland (n  = 16), Finland (n  = 20) and Sweden (n  = 10). Scale growth patterns were measured using numerical analysis to a high accuracy. The results showed that the archaeological population of grayling is closer to the present Finnish population. Furthermore, the comparison of seasonal growth patterns between current and archaeological European populations demonstrated that graylings were normally captured during the spring at Le Taillis des Coteaux Magdalenian site. This type of approach can be used to understand environmental conditions at a low spatial scale and also to help identify fishing seasons during archaeological periods. Copyright © 2017 John Wiley & Sons, Ltd.     

SOIL PHOSPHATE ANALYSIS: A NEW TECHNIQUE FOR MEASUREMENT IN THE FIELD USING A TEST STRIP*

A new method for soil phosphate analysis has been developed for field measurement which will increase the applicability of phosphate mapping in archaeological prospection.     

Breadfruit Fermentation in Pohnpei,Micronesia: Site Formation,Archaeological Visibility,and Interpretive Strategies

Fermentation is a common method of processing and preserving breadfruit throughout the Pacific Islands. While these pits are often reported in the archaeological record, they can pose some interpretive challenges. This paper presents an analysis of probable archaeological breadfruit (Artocarpus altilis (Parkinson) Fosberg) fermentation pits on Temwen Island, Pohnpei, Micronesia. Using the existing ethnographic record as a guide, I present archaeological and paleoethnobotanical criteria for identifying fermentation features. Architectural and stratigraphic analyses from four excavated pits match ethnographic expectations. Phytolith analysis shows some concurrence in terms of taxonomic data, but is more useful for indicating disturbance specific to building activities. Based on the distribution and size of pits present in the survey area, I suggest that breadfruit fermentation took place as primarily a household level (rather than community level) activity during the late prehistoric and early historic period in Pohnpei.     

Multiproxy environmental archaeology of Neolithic settlements at Osłonki,Poland, 5500–4000 BC

Abstract

Archaeological research on Neolithic settlements (ca. 5500–4000 cal BC) at and near Os?onki, Poland, is complemented by palaeoenvironmental investigations in three basins with biogenic sediments adjacent to the archaeological sites. Research included sedimentology, palynology, malacology and cladoceran analysis. Complementary lines of evidence indicate that Linear Pottery pioneer farmers of the late 6th millennium BC caused minimal environmental impact, but intensive settlement and land use by the Brze?? Kujawski Group during the 5th millennium BC triggered pronounced human-induced effects on the local landscape. Of particular significance is the evidence for erosion and aeolian ablation of exposed soil in the vicinity of the Neolithic settlements, presumably reflecting widespread land clearance, agricultural activity and settlement construction.     

HOLOCENE ACCUMULATION OF COLLUVIAL AND ALLUVIAL SEDIMENTS IN THE WEIßE ELSTER RIVER VALLEY IN SAXONY,GERMANY*

Geoarchaeological investigations at two archaeological excavation sites lead to new results with respect to the Holocene landscape development of an archaeologically important loess landscape of Central Europe. Colluvial and alluvial sediments were sampled during archaeological excavations on the valley edge of the Weiße Elster and dated by means of ¹⁴C, TL and dendrochronology, and on the basis of archaeological finds. Thus, for the first time, the development of a valley edge of a river in the Leipzig area, which has been continuously settled for 7300 years, can be reconstructed. The first soil erosion on the valley edge is established towards the end of the Atlantic period. During the High Middle Ages, a colluvial sediment developed. Its deposition time can be limited to between ad 1000 and 1100. The flood loam near Großstorkwitz, which can be stratified by means of the soil and colluvial deposits, originated in the late Sub‐Boreal and early Sub‐Atlantic, as well as after ad 1100. During the first millennium ad, a soil developed in the older flood loam, which indicates a phase of reduced flood loam sedimentation.     

Incremental banding in dental cementum: Methods of preparation for teeth from archaeological sites and for modern comparative specimens

Analysis of incremental banding in dental cementum is a well-established means of determining the age and season of death of wild mammals. The dental cementum of domesticated mammals likewise can indicate age and season of death. Methods of preparation applicable to archaeological teeth differ from those used for modern specimens, however, and this paper describes two methods that have given excellent imaging on teeth of Bos taurus; one for modern teeth and the other for teeth from archaeological sites.