Searching for Scandinavians in pre-Viking Scotland : Molecular fingerprinting of Early Medieval combs

The character and chronology of Norse colonisation in Early Medieval northern Scotland (8th–10th centuries AD) is hotly debated. The presence of reindeer antler raw material in ‘native’ or ‘Pictish’ type combs from the Orkney Isles, northern Scotland has been put forward as evidence for a long and largely peaceful initial period of cultural contact, as opposed to a shorter, more polarised period probably in the late ninth century. Here this hypothesis is tested using a minimally-destructive collagen peptide mass fingerprinting method (ZooMS) to speciate the raw material of 20 combs. Eleven were identified as red deer, four as reindeer and one as whale. The accuracy and gentleness of this method was tested by the subsequent application of ancient DNA (aDNA) methods to fourteen of the same samples: in ten, amplification was successful and all supported the preliminary ZooMS identification. All ‘native’-type combs in the sample are identified as red deer, and all Norse types as reindeer. These results challenge previous species identifications for these combs' raw materials. The balance of evidence no longer supports the existence of a long period of cultural contact between Atlantic Scotland and Scandinavian settlers before the late 9th century. ZooMS is shown to have considerable potential for identification of worked bone and antler artefacts, with applications in archaeology and wildlife/art-history forensics

Provenancing Archaeological Wool Textiles from Medieval Northern Europe by Light Stable Isotope Analysis (δ13C, δ15N, δ2H)

We investigate the origin of archaeological wool textiles preserved by anoxic waterlogging from seven medieval archaeological deposits in north-western Europe (c. 700-1600 AD), using geospatial patterning in carbon (δ13C), nitrogen (δ15N) and non-exchangeable hydrogen (δ2H) composition of modern and ancient sheep proteins. δ13C, δ15N and δ2H values from archaeological wool keratin (n = 83) and bone collagen (n = 59) from four sites were interpreted with reference to the composition of modern sheep wool from the same regions. The isotopic composition of wool and bone collagen samples clustered strongly by settlement; inter-regional relationships were largely parallel in modern and ancient samples, though landscape change was also significant. Degradation in archaeological wool samples, examined by elemental and amino acid composition, was greater in samples from Iceland (Reykholt) than in samples from north-east England (York, Newcastle) or northern Germany (Hessens). A nominal assignment approach was used to classify textiles into local/non-local at each site, based on maximal estimates of isotopic variability in modern sheep wool. Light element stable isotope analysis provided new insights into the origins of wool textiles, and demonstrates that isotopic provenancing of keratin preserved in anoxic waterlogged contexts is feasible. We also demonstrate the utility of δ2H analysis to understand the location of origin of archaeological protein samples

A light stable isotope (C, N, H, O) approach to identifying movement of medieval textiles in North West Europe

This thesis examined how light stable isotopic analysis could be used to examine the provenance of archaeological wool textiles preserved by anoxic waterlogging. Preliminary studies in modern sheep wool samples showed that their carbon (δ13C), nitrogen (δ15N), un-exchangeable hydrogen (δ2H) and oxygen (δ18O) composition varied systematically with geographical location in British Isles and Iceland, but were significantly influenced by farming practice (fodder provision, fertilizer use). Keratin and collagen isotope values within a single sheep were shown to be systematically related. Experimental characterisation of the isotopic effects of wool degradation by elemental, amino acid and isotopic composition showed that changes in experimentally buried samples were minimal compared to samples treated under high-temperature hydrous conditions, which showed significant hydrolysis, oxidation and racemisation. These results were used to interpret data from 101 archaeological textiles from contexts dated between AD 7001600 from excavations at Reykholt, Iceland; York and Newcastle, Britain; Hessens, Germany; and Birka, Sweden. Local isotope range for each location was defined by assemblage median ± maximum variation derived from a modern flock. Isotopic identifications of local/non-local wool did not always correspond to typical/atypical interpretations of textile origin based on features of textile construction, fibre type and dye use. Thus distinctions could be made between the movement of textiles (atypical construction, non-local composition), movement of textile techniques (atypical construction, local composition) and movement of raw wool (typical construction, non-local composition). The most significant limitation of the technique was insufficient isotopic difference between regions of origin and deposition. The results made a significant contribution to understanding the origin of a number of specific textile types, including the much-discussed ‘Frisian cloth’

Dents in our confidence: The interaction of damage and material properties in interpreting use-wear on copper-alloy weaponry

Abstract The presence or absence of use-wear marks on copper (Cu)-alloy weaponry has been used since the late 1990s to investigate the balance between functional (combat) and symbolic (value, status, religious) use of these objects, and thus explore their social and economic context. In this paper, we suggest that this work has not taken sufficient account of the material properties of Cu-alloys. We discuss mechanisms of plastic deformation, incremental repairs and corrosion in detail to show how these can obscure use-wear traces. In a survey of Cu-alloy weaponry from the Nordic Bronze Age (1800/1700–550 BCE) from Denmark, Sweden and Germany, we show that corrosion of Cu-alloy objects is strongly linked to depositional context, being greater in burials (both inhumations and cremations) than hoards or as single objects. A relative paucity of use-wear marks on burial weapons should therefore not be used to argue that these were purely symbolic objects, e.g. in contrast to the better preserved hoard material. We propose that use-wear traces on Cu-alloy weaponry, particularly on blade edges, is significantly more elusive than previously realised, and that undamaged objects have been over-identified

Neodymium and strontium isotope analysis of modern human dental enamel using Thermal Ionization Mass Spectrometry (TIMS)

This dataset contains the numerical data underlying the publication figures and conclusions (Plomp et al. 2017, 2019)

Collagen proteins exchange oxygen with demineralisation and gelatinisation reagents and also with atmospheric moisture.

RATIONALE: The oxygen (O) isotope composition of collagen proteins is a potential indicator of adult residential location, useful for provenancing in ecology, archaeology and forensics. In acidic solution, proteins can exchange O from carboxylic acid moieties with reagent O. This study investigated whether this exchange occurs during demineralisation and gelatinisation preparation of bone/ivory collagen. METHODS: EDTA and HCl demineralisation or gelatinisation reagents were made up in waters with different δ18 O values, and were used to extract collagen from four skeletal tissue samples. Aliquots of extracted collagen were exposed to two different atmospheric waters, at 120°C and ambient temperature, and subsequently dried in a vacuum oven at 40°C or by freeze drying. Sample δ18 O values were measured by HT-EA pyrolysis/IRMS using a zero-blank autosampler. RESULTS: Collagen samples exchanged O with both reagent waters and atmospheric water, which altered sample δ18 O values. Exchange with reagent waters occurred in all extraction methods, but was greater at lower pH. Damage to the collagen samples during extraction increased O exchange. The nature of exchange of O with atmospheric water depended on the temperature of exposure: kinetic fractionation of O was identified at 120°C but not at ambient temperature. Exchange was difficult to quantify due to the high variability of δ18 O values between experimental replicates. CONCLUSIONS: Studies of δ18 O values in collagen proteins should avoid extraction methods using acidic solutions

TIMS analysis of neodymium isotopes in human tooth enamel using 1013 Ω amplifiers

Human provenance studies employing isotope analysis are essential in archaeological and forensic sciences but current applications provide limited spatial resolution. This study reports on the potential of neodymium isotope composition (143Nd/144Nd) to improve human provenancing capabilities. Human tissues contain very low (<0.1 ppm) neodymium concentrations, such that previous composition analysis was not possible. Additionally, Nd composition analysis in human enamel is hindered by Ca in the sample matrix. A modified Nd chromatographic separation technique is reported here, which removes large Ca quantities and accommodates large sample sizes (300-1000 mg). Verification of the modified chromatographic procedure was achieved using an internal synthetic tooth standard. These advancements allow for high precision Nd isotope composition analysis on ~500 mg of tooth enamel, or >100 pg of Nd, by thermal ionization mass spectrometry (TIMS) using 1013 Ω resistors. Neodymium concentrations in enamel from third molars of modern Dutch residents range between 0.1-21.0 ppb (n = 23). The 143Nd/144Nd values for Amsterdam (0.51204-0.51259, n = 12) and Rotterdam (0.51187-0.51239, n = 8) are significantly different (P value = 0.02), demonstrating the potential of neodymium isotope composition to provide improved spatial resolution. Further assessment of Nd composition in enamel of residents from other geological contexts is required to better understand the human provenance capabilities of neodymium

TIMS analysis of neodymium isotopes in human tooth enamel using 1013 Ω amplifiers

Human provenance studies employing isotope analysis are essential in archaeological and forensic sciences but current applications provide limited spatial resolution. This study reports on the potential of neodymium isotope composition (143Nd/144Nd) to improve human provenancing capabilities. Human tissues contain very low (<0.1 ppm) neodymium concentrations, such that previous composition analysis was not possible. Additionally, Nd composition analysis in human enamel is hindered by Ca in the sample matrix. A modified Nd chromatographic separation technique is reported here, which removes large Ca quantities and accommodates large sample sizes (300-1000 mg). Verification of the modified chromatographic procedure was achieved using an internal synthetic tooth standard. These advancements allow for high precision Nd isotope composition analysis on ~500 mg of tooth enamel, or >100 pg of Nd, by thermal ionization mass spectrometry (TIMS) using 1013 Ω resistors. Neodymium concentrations in enamel from third molars of modern Dutch residents range between 0.1-21.0 ppb (n = 23). The 143Nd/144Nd values for Amsterdam (0.51204-0.51259, n = 12) and Rotterdam (0.51187-0.51239, n = 8) are significantly different (P value = 0.02), demonstrating the potential of neodymium isotope composition to provide improved spatial resolution. Further assessment of Nd composition in enamel of residents from other geological contexts is required to better understand the human provenance capabilities of neodymium

Reprint of: The effects of decomposition and environment on antemortem H-Pb-Sr isotope compositions and degradation of human scalp hair:Actualistic taphonomic observations

Multi-isotope analysis (e.g., Sr-Pb-O-H-C-N) of human scalp hair is routinely used in forensic investigations of human remains to constrain the geographic origin of unidentified bodies, and to investigate antemortem mobility patterns. However, while it is known that postmortem processes can affect the preservation of, or even overprint, the biogenic isotopic signatures in hair, the speed and nature of these processes have rarely been studied. This study investigates the effects of decomposition and environment on the H-Pb-Sr isotope compositions of human hair as well as the relationship between structural hair shaft degradation and isotopic signature change over time. Human scalp hair samples from four body donations were collected at different stages throughout gross body decomposition. The willed-donated bodies were placed to decompose outdoors at the Forensic Anthropology Research Facility (FARF) at Texas State University. Hair fibres from two of the donations were examined using scanning electron microscopy (SEM) and high-resolution light microscopy (HRLM). Chemical and microbiological degradation of hair fibres occurred rapidly after placement of the body outdoors. Measurements of scalp hair isotopic composition demonstrated that H-Pb-Sr isotope ratios were altered within days after environmental exposure, presumably by deposition, leaching and/or exchange with the local bioavailable soil, and vapour. The degree of physical hair degradation and changes in H-Pb-Sr isotope composition were not correlated. We conclude that antemortem isotopic H-Pb-Sr isotope ratios are difficult to recover in hairs derived from decomposing whole bodies