Neutron activation data for the analysis of archaeological and geological hematite in Missouri and Illinois, U.S.A

Hematite, and more broadly ochre, have long been used by humans throughout history for a variety of applications. In prehistoric North America the use of hematite is as old as its first migrants. This data article includes data related to the analysis of archaeological hematite in the American Bottom region in Missouri and Illinois, U.S.A. The data include archaeological samples dating from the Late Archaic Period (3000 - 1000 BCE) to the Middle Woodland Period (150 BCE - 400 CE) from nine sites within the general St. Louis area (n = 69), as well as 29 samples from Verkamp Rockshelter in the iron-rich region of the Meramec River Valley. The data is supplemented with geological samples collected from five raw deposits in southeastern Missouri (n = 70). Data was acquired through Neutron Activation Analysis to assess provenance of all archaeological samples. Following the irradiation of samples, data was normalized for iron content before statistical analysis. A variety of multivariate statistical routines, including principal component and cluster analyses were then employed to assess possible origin locales for all archaeological samples. This data article also includes maps, tables, and figures to assist in understanding the analysis conducted.

To glove or not to glove? Investigations into the potential contamination from handling of paper-based cultural heritage through forensic fingerprinting approaches

The handling of cultural heritage objects has become a highly debated topic in the last decade. The work and outcomes described in this paper are aimed to provide objective data to assist in making appropriate decisions as to whether or not wearing gloves is appropriate in a given situation. The forensic fingermark development techniques of 1,2-indandione and single metal deposition II were used to investigate the efficacy of handwashing and glove use to improve the information available when deciding whether to use gloves when handling paper objects. It was found that fingermarks did not permeate through polymer glove types but could through cotton gloves. It was also shown that the amounts of observable fingermark residues were greater 5 min after handwashing than if handwashing had not occurred, undermining previous arguments for not wearing gloves if hands could be washed before object handling.

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Fingermarks can be transferred onto paper even after washing hand.

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Developed fingermark residues initially increase after handwashing.

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Handwashing is not sufficient to prevent fingermark contamination of artifacts.

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Fingermark residues can be transferred from surfaces to gloves to paper.

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Some antibacterial gels can increase the amount of fingermark residue deposited.

Radionuclides and stable elements in vegetation in Australian arid environments: Concentration ratios and seasonal variation

Data on the uptake of elements and radionuclides by flora from soils in arid environments are underrepresented in international databases, especially when comparing across seasons. This study improved the understanding on the uptake of natural uranium-series radionuclides, as well as more than 30 elements, in a range of Australian native flora species that are internationally representative of an arid/semi-arid zone (e.g. Acacia, Astrebla, Atriplex, and Dodonea). Results indicate that the soil-to-plant uptake ratios were generally higher when compared with international data for grasses and shrubs from more temperate environments. The majority of the elemental concentrations in grasses were higher in winter than in summer and the opposite trend was found in shrubs, which suggests that the season of collection potentially introduces variability in the reported concentration ratios. The data also suggest that grasses, being dominant and widespread species in arid zones, may be effective as a reference organism to ensure comparative assessment across sites of interest. The results of this study will improve the confidence of environmental assessments in arid zones.

Phase Analysis of Australian Uranium Ore Concentrates Determined by Variable Temperature Synchrotron Powder X-ray Diffraction

The chemical speciation of uranium oxides is sensitive to the provenance of the samples and their storage conditions. Here, we use diffraction methods to characterize the phases found in three aged (>10 years) uranium ore concentrates of different origins as well as in situ analysis of the thermally induced structural transitions of these materials. The structures of the crystalline phases found in the three samples have been refined, using high-resolution synchrotron X-ray diffraction data. Rietveld analysis of the samples from the Olympic Dam and Ranger uranium mines has revealed the presence of crystalline α-UO₂(OH)₂, together with metaschoepite (UO₂)₄O(OH)₆·5H₂O, in the aged U₃O₈ samples, and it is speculated that this forms as a consequence of the corrosion of U₃O₈ in the presence of metaschoepite. The third sample, from the Beverley uranium mine, contains the peroxide [UO₂(η²-O₂)(H₂O)₂] (metastudtite) together with α-UO₂(OH)₂ and metaschoepite. A core-shell model is proposed to account for the broadening of the diffraction peaks of the U₃O₈ evident in the samples.

Consumption and exchange in Early Modern Cambodia: NAA of brown-glaze stoneware from Longvek, 15th-17th centuries

An evaluation of the geochemical characteristics of 102 storage jar sherds by k₀-neutron activation analysis (k₀-NAA) from archaeological contexts in Cambodia and reference samples from stoneware production centres in Thailand provides a new perspective on regional and global trade in mainland Southeast Asia. Identification of seven geochemical groups enables distinctions between production centres, and articulation of their role in trade between northern and central Thailand, South China and Cambodia. Storage jars from Thailand and South China are known in archaeological contexts worldwide because of their durability and intrinsic functional and cultural values. Evidenced by a novel application of k₀-NAA, analogous stoneware sherds at Longvek connect the Cambodian capital to a global trading network. Additional proof of ceramics from an undocumented Cambodian kiln demonstrates the gradual and complex transition between the Angkorian past and the Early Modern period.

Methods for analysis of glass in glass-containing gunshot residue (gGSR) particles

When lead, barium and antimony, or lead, barium, calcium, silicon and tin are found together in particles associated with a shooting investigation they are considered characteristic of gunshot residue (GSR). Antimony and tin are often absent from the primer of many low calibre rimfire ammunitions, which are the type most commonly used in Australia. Therefore, the likelihood of characteristic particles forming during the firing process of such rimfire ammunition is significantly less than the likelihood of these particles arising from higher calibre ammunition. The majority of rimfire ammunition examined in this research contains ground glass in the primer, which functions as a frictionator. These ammunitions produce a small number of gunshot residue particles containing glass coated with other primer components, which we refer to as glass-containing GSR (gGSR). If these particles are observed in an investigation, they have the potential to add a new dimension to gunshot residue analysis because they are not common in the environment. Furthermore, the composition of glass frictionator is stable during firing, which raises the possibility that chemical testing of the glass in gGSR may be used to identify the ammunition from which the residue was derived or to link deposits of GSR. This paper examines the application of scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDS), focussed ion beam (FIB) techniques and time of flight-secondary ion mass spectrometry (ToF-SIMS) to the semi-quantitative analysis and comparisons of gGSR and frictionator extracted from unfired cartridges. SEM-EDS is effective for comparing gGSR with unfired frictionator, but the use of FIB to expose clean glass from the centre of gGSR followed by ToF-SIMS, or ToF-SIMS using ion sputtering to expose clean glass, offers more power for comparisons due to their capability for higher discrimination between frictionators from different sources.

Microbial composition analyses by 16S rRNA sequencing: A proof of concept approach to provenance determination of archaeological ochre

Many archaeological science studies use the concept of “provenance”, where the origins of cultural material can be determined through physical or chemical properties that relate back to the origins of the material. Recent studies using DNA profiling of bacteria have been used for the forensic determination of soils, towards determination of geographic origin. This manuscript presents a novel approach to the provenance of archaeological minerals and related materials through the use of 16S rRNA sequencing analysis of microbial DNA. Through the microbial DNA characterization from ochre and multivariate statistics, we have demonstrated the clear discrimination between four distinct Australian cultural ochre sites.

Novel application of X-ray fluorescence microscopy (XFM) for the non-destructive micro-elemental analysis of natural mineral pigments on Aboriginal Australian objects

This manuscript presents the first non-destructive synchrotron micro-X-ray fluorescence study of natural mineral pigments on Aboriginal Australian objects. Our results demonstrate the advantage of XFM (X-ray fluorescence microscopy) of Aboriginal Australian objects for optimum sensitivity, elemental analysis, micron-resolution mapping of pigment areas and the method also has the advantage of being non-destructive to the cultural heritage objects. Estimates of pigment thickness can be calculated. In addition, based on the elemental maps of the pigments, further conclusions can be drawn on the composition and mixtures and uses of natural mineral pigments and whether the objects were made using traditional or modern methods and materials. This manuscript highlights the results of this first application of XFM to investigate complex mineral pigments used on Aboriginal Australian objects.

Glass fragments from portable electronic devices: Implications for forensic examinations

Personal electronic devices (PEDs) are now widespread in the community. Many such devices have glass display screens that, despite being a relatively strong and specialised material, are vulnerable to breakage. Unlike other glass objects that are usually thrown away when they break, PEDs can still function with a broken or cracked screen and it is not uncommon for their owners to keep using them in this condition. Broken PED screens, therefore, might represent a new and significant source of glass fragments that are present on the clothing and belongings of the general public and individuals suspected of offences involving the breaking of glass. The forensic implications of this new source of glass fragments in the community were investigated. PED glass is easily recognised using scanning electron microscopy-energy dispersive X-ray analysis and refractive index measurement and is easily distinguished from domestic and automotive soda-lime glass using these methods; as a consequence there should be no confusion of soda-lime glass fragments and PED glass fragments in forensic glass casework. In cases where the objective is to compare recovered glass fragments to a putative PED source, comparison using refractive index measurement and elemental analysis achieves good discrimination between sources.

Non-labile silver species in biosolids remain stable throughout 50 years of weathering and ageing

Increasing commercial use of nanosilver has focussed attention on the fate of silver (Ag) in the wastewater release pathway. This paper reports the speciation and lability of Ag in archived, stockpiled, and contemporary biosolids from the UK, USA and Australia, and indicates that biosolids Ag concentrations have decreased significantly over recent decades. XANES revealed the importance of reduced-sulfur binding environments for Ag speciation in materials ranging from freshly produced sludge to biosolids weathered under ambient environmental conditions for more than 50 years. Isotopic dilution with (110 m)Ag showed that Ag was predominantly non-labile in both fresh and aged biosolids (13.7% mean lability), with E-values ranging from 0.3 to 60 mg/kg and 5 mM CaNO3 extractable Ag from 1.2 to 609 μg/kg (0.002-3.4% of the total Ag). This study indicates that at the time of soil application, biosolids Ag will be predominantly Ag-sulfides and characterised by low isotopic lability.

Towards identification of traditional European and indigenous Australian paint binders using pyrolysis gas chromatography mass spectrometry

We report a pyrolysis GC-MS method capable of analysing Indigenous Australian and European binders typically used in the manufacture of culturally important painted works. Eleven different traditional European binders and ten different Indigenous Australian binders were examined. The method allows discrimination between highly complex and impure lipid, resin, polysaccharide, wax, and protein-based binders. Each was found to have characteristic pyrolysis products that were unique to the binder material, demonstrating the potential for differentiation of these binders on Australian Aboriginal artworks towards identification and conservation of cultural heritage.