LA-ICP-MS Research Papers - Academia.edu (original) (raw)

We report experiments on optimisation of LA-ICP-MS mapping as a tool for visualising and quantifying internal structure of trace element concentration in igneous minerals. The experimental design was refined with maps on clinopyroxene and... more

We report experiments on optimisation of LA-ICP-MS mapping as a tool for visualising and quantifying internal structure of trace element concentration in igneous minerals. The experimental design was refined with maps on clinopyroxene and amphibole macrocrysts (mainly antecrysts) from a porphyritic lamprophyre in NE Spain, as well as on a high precision metal wire grid. In terms of spatial resolution, we demonstrate with scanning electron microscope and white light interferometry that a full ablation removes between 0.4 and 0.7 μm of material, depending on ablation parameters. Maps were produced with square laser beam spots of 12 and 24 μm. It was found that complexities can be resolved in the sample even though they are smaller than the beam diameter (e.g., 7–10 μm discontinuities using 12 μm laser beam). Resolution in x and y was found to be identical, probably reflecting the fast washout of the two-volume ablation cell and the short total dwell time of the analyte menu selected. Due to the excellent stage reproducibility and the limited ablation depth, it is feasible to re-ablate the identical map area many times employing different instrument parameters or analyte menus. On the magmatic crystals, LA-ICP-MS maps define very sharp compositional zoning in trace elements, highlighting complex crystallisation histories where 'normal' magmatic fractionation is not the only process. Events of mafic recharge are easily recognised as zones enriched in compatible metals such as Cr, Ni or Sc. Further, trace element maps reveal complexities in mineral zoning previously undetectable with petrography or major element data. These include resorbed primitive cores and oscillatory zoning within apparently homogeneous mineral zones. Therefore, LA-ICP-MS mapping opens a new window of opportunity for analysis of magmatic histories. The wide combination of instrumental parameters, such as laser beam size, scan speed and repetition rate, make it possible to carry out experiments at different levels of detail. We recommend a two-step approach to mapping. The initial step involves rapid maps to gain an overview of potential complexities in the sample; this enhances representativeness of the analysed materials, as a large number of crystals and trace elements can be tested in little time. Subsequently, detailed maps can be carried out on areas of interest. An additional function-ality is to create 1D-profiles from 2D-maps. The potential of the technique to unveil compositional complexities efficiently and at greater detail than traditional microanalysis will help to improve our understanding of processes in the magmatic environment and beyond.

Sourcing artifacts is a key method for addressing anthropological issues of mobility and interaction. Although chert was one the most common toolstones used in prehistory, sourcing chert artifacts remains problematic. In this study an... more

Sourcing artifacts is a key method for addressing anthropological issues of mobility and interaction. Although chert was one the most common toolstones used in prehistory, sourcing chert artifacts remains problematic. In this study an approach for sourcing chert is introduced that links a specific sampling protocol, Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), and multivariate statistical analysis. The effectiveness of this approach is demonstrated through a controlled experiment examining intersource and intrasource variability at four different scales of analysis. The statistical analysis at four spatial scales allows determination of the spatial resolution of the chemical matching procedure outlined here. In this experiment geologic chert samples from the Edwards Plateau of Texas of known provenience are chemically evaluated allowing comparison of their expected origin against their known origin. This experiment used Edwards Plateau chert as it is a high quality material and was a major lithic source across the Southern High Plains and was often transported great distances. Macroscopic identification of Edwards Plateau chert can be problematic and at its best is unable to effectively discern from where within the 120,000 km2 of the region cherts originated. An understanding of the geological formation processes of chert provides a useful framework for addressing this issue. This study shows that through an effective methodology Edwards Plateau chert can be sourced to a finer spatial scale than previous studies.

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 –... more

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.

Recently facial makeup cosmetic products have become very popular among Sudanese women in spite of the fact that they might contain toxic materials including Pb, Hg, Cd, As, Ni and Zn, and their use as ingredients in cosmetics is... more

Recently facial makeup cosmetic products have become very popular among Sudanese women in spite of the fact that they might contain toxic materials including Pb, Hg, Cd, As, Ni and Zn, and their use as ingredients in cosmetics is prohibited as they cause skin problems. Owing to the absence of control standards of these products sold in Sudanese markets, the present study aimed at developing a method for the determination of these metals by inductively coupled plasma – mass spectrometry (ICP-MS). Eighty-six samples of different facial makeup cosmetic products were collected randomly from the local Sudanese markets. A microwave-assisted digestion with a mixture of concentrated nitric acid and hydrochloric acid was applied for sample preparation. The concentration of each metal was determined in triplicate by ICP-MS. For eye shadow, in a wide range of concentrations, all analyzed elements were detected at high levels in the imported samples, but Pb, Hg, and Cd were detected at low levels in the locally prepared not only eye shadow but also lipstick samples. Although Pb was present at low concentrations in all samples, locally prepared whitening creams, lipstick, and eye shadow showed highest concentration levels of 33.63 µg /g, 42.42 µg /g, and 52.02 µg /g, respectively. The highest concentration levels for Hg in locally prepared whitening creams and eye shadow samples were found to be 42.09 µg /g, and 21.30 µg /g, respectively. The highest concentration levels for Cd, however, were found to be 5.21 µg /g, 22.53µg /g, and 7.06µg /g, in imported lipstick, eye shadow, and local whitening creams, respectively. High concentration levels of Zn were not obtained in all analyzed samples except in the imported eye shadow, (72.46µg /g). The determination of heavy metals in cosmetic products sold in Sudanese markets increase the needs to set laws to regulate their preparation locally and to set standards to control their quality and safety.

The Archaean Yilgarn Craton (Western Australia) is a world-class metallogenic province, hosting considerable resources of Au, Ag, Ni, Cu, Zn and Fe. Here we present trace element compositions of pyrite from N30 orogenic Au and 5 volcanic... more

The Archaean Yilgarn Craton (Western Australia) is a world-class metallogenic province, hosting considerable resources of Au, Ag, Ni, Cu, Zn and Fe. Here we present trace element compositions of pyrite from N30 orogenic Au and 5 volcanic hosted massive sulphide (VHMS) deposits across the Yilgarn. Pyrites from VHMS deposits tend to have higher Sn, Se, Cu, Pb, Bi and lower Ni relative to orogenic deposits. VHMS deposit pyrites commonly have Co N Ni, As N 100Au, Te N Au, Se N Te. Orogenic gold deposits could be subdivided based on association of Au with As or Te. Pyrites from Au\ \As ores generally have Pb/Bi N 5, Se/Te N 5, Pb/Sb b 5 and Tl/Te N 100 and the majority of Au is refractory (in pyrite structure). At the same time Au\ \Te association pyrites are characterised by lower values of Pb/Bi, Se/Te and Tl/Te, higher values of Ag/Au, Pb/Sb and Au generally resides in inclusions of different compositions. Our data can be used at the exploration stage to distinguish between VHMS vs Orogenic Au signatures. For all studied deposits inclusion populations are summarised with implications for Au and Ag deportment. Orogenic Au deposits from the Yilgarn mostly have multistage formation histories reflected in the presence of multiple generations of pyrites. However, only some deposits record multiple high Au mineralisation events.

Germanium, gallium and indium are in high demand due to their growing usage in high-tech and green-tech applications. However, the mineralogy and the mechanisms of concentration of these critical elements in different types of... more

Germanium, gallium and indium are in high demand due to their growing usage in high-tech and green-tech applications. However, the mineralogy and the mechanisms of concentration of these critical elements in different types of hydrothermal ore deposits remain poorly constrained. We investigated the mineralogical distribution of Ge, Ga and In at the Mt Carlton high-sulfidation epithermal deposit in NE Australia, using electron probe microanalysis and laser ablation inductively-coupled plasma mass spectrometry. Parageneses from which selected minerals were analyzed include: Stage 1 acid sulfate alteration (alunite), Stage 2A high-sulfidation enargite mineralization (enargite, argyrodite, sphalerite, pyrite, barite), Stage 2B intermediate-sulfidation sphalerite mineralization (sphalerite, pyrite, galena) and Stage 3 hydrothermal void fill (dickite). Moderate to locally high concentrations of Ga were measured in Stage 1 alunite (up to 339 ppm) and in Stage 3 dickite (up to 150 ppm). The Stage 2A ores show enrichment in Ge, which is primarily associated with argyrodite (up to 6.95 wt % Ge) and Ge-bearing enargite (up to 2189 ppm Ge). Co-existing sphalerite has comparatively low Ge content (up to 143 ppm), while Ga (up to 1181 ppm) and In (up to 571 ppm) are higher. Sphalerite in Stage 2B contains up to 611 ppm Ge, 2829 ppm Ga and 2169 ppm In, and locally exhibits fine colloform bands of an uncharacterized Zn-In mineral with compositions close to CuZn 2 (In,Ga)S 4. Barite, pyrite and galena which occur in association with Stage 2 mineralization were found to play negligible roles as carriers of Ge, Ga and In at Mt Carlton. Analyzed reference samples of enargite from seven similar deposits worldwide have average Ge concentrations ranging from 12 to 717 ppm (maximum 2679 ppm). The deposits from which samples showed high enrichment in critical elements in this study are all hosted in stratigraphic sequences that locally contain carbonaceous sedimentary rocks. In addition to magmatic-hydrothermal processes, such rocks could potentially be important for the concentration of critical elements in high-sulfidation epithermal deposits.

This thesis demonstrates the application of a number of analytical techniques on a selection of silver coins from the Western Australian Museum. Results of analysis are used to appraise the applicability of surface analytical techniques... more

This thesis demonstrates the application of a number of analytical techniques on a selection of silver coins from the Western Australian Museum. Results of analysis are used to appraise the applicability of surface analytical techniques on samples that have corroded. Analysis has also been used to determine when, where and how coins too heavily corroded to visually identify were minted. Further, the importance of maintaining large collections and assemblages of objects in museum collections is demonstrated, and further applications of the techniques used are discussed.
Four hundred silver coins and a selection of silver artefacts were provided for analysis from the collection of the Western Australian Museum. The coins and artefacts were recovered from the following shipwrecks; the Batavia wrecked 1629; the Vergulde Draeck, wrecked 1656; the Zuytdorp, wrecked 1712; the Rapid, wrecked 1811; and the Correio da Azia, wrecked 1816. All of the ships were wrecked off the coast of Western Australia. The coins represent 22 mints in Spain, Spanish America, the United Netherlands, Germany, and the Spanish Netherlands, and 19 European sovereign issuers from Spain, Saxony, the Holy Roman Empire, Denmark and Norway, the United Netherlands, Holstein Gottorp, and Saxe-Coburg Saxe-Eisenach. The coins were minted between 1560 and 1816.
Samples were analysed using non-destructive analytical techniques: inductively coupled plasma mass spectrometry (ICP-MS) and scanning electron microscopy (SEM). These semi-destructive techniques were chosen in order to demonstrate their effectiveness in gleaning further information from items of cultural heritage significance, than is possible through a visual analysis alone. Silver coins and artefacts were chosen for analysis due to the large assemblage of silver coins held by the Western Australian Museum, making it possible to create a database of analytical results from coins of both known and unknown mint of origin and year of minting for the sake of effective comparison.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), a technique which facilitates multi-element analysis without causing significant damage to the coins themselves. Thirty-eight elements were determined in triplicate for each coin thereby providing individual elemental “fingerprints”. Data were interpreted using linear discriminant analysis (LDA) which allows the coins to be grouped into easily identifiable sub-groups. Using LA-ICP-MS plus LDA it was possible to use the trace and minor element composition of the coins to identify chemical signatures which are specific to the mints of origin. This information was then cross-referenced against the trace and minor elemental composition of damaged and unidentifiable coins to determine their mint of origin and year or decade of minting.
A selection of samples was also analysed using scanning electron microscopy (SEM), a technique which facilitates further understanding of the manufacturing history of the samples based on backscattered electron (BSE) images and electron backscatter diffraction (EBSD) structural maps. Diffracted backscattered electron images can be used to assess the crystallographic structure of the sample and to assess areas of possible inhomogeneity, both of which are indicative of techniques used to manufacture objects of silver and silver alloys. This analysis complements LA-ICP-MS analysis by providing the manufacturing history of the samples, on top of the identification of their provenance and year of manufacture.
This research gives new information about economic networks, including trade between the Americas, Europe and the Far East during the 16th, 17th and 18th centuries, the height of the great maritime empires, and more specifically, the procurement, manufacture and trade of silver as a global commodity at this time. Further, the techniques used in this study are applicable to many other items of cultural heritage significance for future analysis.

Beads made of glass and stone found at Iron Age period sites (500 BC – AD 500) in Southeast Asia are amongst the first signs for sustained trade and sociopolitical contact with South Asia. Because of this, they have become important... more

Beads made of glass and stone found at Iron Age period sites (500 BC – AD 500) in Southeast Asia are amongst the first signs for sustained trade and sociopolitical contact with South Asia. Because of this, they have become important artifacts for scholars wishing to better understand trade networks and sociopolitical development during this period. Using compositional analysis scholars can identify the recipes used to make these glass beads and in some cases this can be tied back to specific places or time periods. Current research indicates there were multiple glass bead production centers across South and Southeast Asia during this period. However there has not yet been a comprehensive examination of glass beads from Iron Age sites in Cambodia. This paper aims to fill this gap by presenting the results from a compositional analysis of glass beads from six Iron Age sites in Cambodia. Using a virtually non-destructive compositional technique (LA-ICP-MS), I was able to determine the presence of at least two glass bead-trading networks in Cambodia during the Iron Age.

Base glasses from the eastern Mediterranean which circulated in Rome between the fifth and tenth centuries bear witness to the persistence of long-distance trade after the fall of the Western Roman Empire. LA-ICP-MS data of vessel... more

Base glasses from the eastern Mediterranean which circulated in Rome between the fifth and tenth centuries bear witness to the persistence of long-distance trade after the fall of the Western Roman Empire. LA-ICP-MS data of vessel fragments, mosaic tesserae and indicators of production excavated in the Forum of Caesar identify a substantial amount of recycled Roman base glass mixed with later Foy.2.1 glass, flanked by Roman Mn and Sb, Foy 2.1, Foy 3.2, HIMT and Levantine I base glass. Recycled compositions have been documented since the fifth century. Base glasses dating later than the seventh century are completely missing, indicating an interruption or a strong contraction of the commercial flows sometime in the seventh century. The identification of a small number of medieval vessels is coherent with the presence in the area of a dwelling context of elevated status. The compositional features of these glasses reflect the intensification of recycling in the eight century, when the commerce of cullet became increasingly international and some fresh glass continued to travel along the Adriatic trade routes.

Outstanding garnet beads were found recently in an elite tumulus dated to the fourth century AD and located at the cemetery of Hagar el‐Beida in the Upper Nubian Nile Valley region. Whereas contacts of Northeast Africa with South Asia... more

Outstanding garnet beads were found recently in an elite tumulus dated to the fourth century AD and located at the cemetery of Hagar el‐Beida in the Upper Nubian Nile Valley region. Whereas contacts of Northeast Africa with South Asia have just been proven through analysis of glass beads found in Nubia and dating to the time of intensive Indian Ocean trade, scientific evidence for Nubia's link with the regions to the west was lacking. Laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) was used to determine the elemental composition of three garnet beads to gain information about their type and origin. Additionally, we analyzed twelve garnets from two nearby alluvial placer deposits. While the garnet beads are inclusion‐free Cr‐poor and Ti‐rich pyropes related to alkaline mafic volcanic rocks, the local garnet deposits are shown to be inclusion‐rich almandines and thus unrelated to the investigated Nubian beads. Detailed comparison of data from Merovingian cloisonné jewellery and all known sources of the Cr‐poor and Ti‐rich pyropes shows identical ranges of elemental contents. The source of raw materials for the beads found in Nubia has been not identified with certainty yet, but sources in Portugal and Nigeria are suggested and a connection is shown to similar garnets from Merovingian contexts.

The Sullivans Island glass bead collection at the Smithsonian's National Museum of Natural History contains over 56,000 beads which date from the late 18th to the late 19th century. Excavated in the 1930s from a site on the Columbia River... more

The Sullivans Island glass bead collection at the Smithsonian's National Museum of Natural History contains over 56,000 beads which date from the late 18th to the late 19th century. Excavated in the 1930s from a site on the Columbia River in the Plateau region of North America, this collection contains examples of most known bead varieties for this time period. Many of the beads conform to varieties that have been attributed to Bohemia, Venice, and China-three of the main bead-producing centers for this time period. One hundred and twenty-four beads were subjected to Laser-Ablation Inductively-Coupled Mass-Spectrometry (LA-ICP-MS) analysis at the Smithsonian's Materials Conservation Institute to see if the chemical composition of the glass could be correlated with a place of origin. The results revealed several distinct compositional groups, some of which could be linked to geographical areas.

Around the Indian Ocean, the use of glassware was unknown with a few exceptions until about the 9th c. A. D. Starting around that time, following the expansion of Islam, Muslims merchants developed trade around the Indian Ocean and signs... more

Around the Indian Ocean, the use of glassware was unknown with a few exceptions until about the 9th c. A. D. Starting around that time, following the expansion of Islam, Muslims merchants developed trade around the Indian Ocean and signs of their growing activities appear at many sites in various forms, one of them being glassware. In order to reconstruct the routes that channeled glassware to the Indian Ocean, this presentation will report on the LA-ICP-MS (laser ablation – inductively coupled plasma – mass spectrometry) analysis of glass samples from the Egyptian site of Quseir Al-Qadim. The Oriental Institute (Chicago, USA) is housing part of the Quseir Al-Qadim glass collection excavated by Dr Janet H. Johnson and Dr Donald S. Whitcomb in 1978, 1980 and 1982. Approximatively 25 glass samples held at this institution and dating from the Mamluk period were selected by Carole Mayer in 2013 and this presentation will report on their compositions. The glass from Quseir Al-Qadim was certainly not manufactured on-site, but the Red Sea was an important transit point for goods, such as glass, in route to the Indian Ocean. The narrow dating interval attributed to the studied glass material (13th – 14th c. A.D.) is giving us a snapshot of the glass types circulating at this period .We found similarities between the glass compositions found at Quseir Al-Qadim and at different sites in Africa and in Southeast Asian where contemporaneous material was discovered and studied.

Előadásunk kiindulópontja Nyírparasznya – III. forduló szkíta kori településének ,,import” kerámiáinak régészeti-ásványtani vizsgálata, ugyanakkor a hasonló korú Nagytarcsa – urasági-dűlői lelőhely anyagát is közzé tesszük. Munkánk a... more

Előadásunk kiindulópontja Nyírparasznya – III. forduló szkíta kori településének ,,import” kerámiáinak régészeti-ásványtani vizsgálata, ugyanakkor a hasonló korú Nagytarcsa – urasági-dűlői lelőhely anyagát is közzé tesszük. Munkánk a lelőhelyek komplex feldolgozásába illeszkedik, és noha a vizsgálatok elsődleges célja a régészeti értelmezés megerősítése, illetve finomítása volt, mára önálló kutatási programmá kezdi kinőni magát. Ennek súlyponti kérdései a szkíta kori fazekasság alaprétegeinek szétbontása, a technológiai innovációk (korongolás) beépülésének vizsgálata és az import kerámiák széleskörű elemzése. Vizsgálataink során igyekeztünk a lehető legteljesebb mértékben megjeleníteni a szkíta kori Alföld-csoport kerámiájának alapformáit és technológiai változatosságát, emellett különösen nagy gondot fordítottunk az ,,import” árukra. A kerámiák szövetének makroszkópos megfigyelése után 55 (Nyírparasznya) mintából készítettünk vékonycsiszolatot, ezen túlmenően pedig a nagytarcsai kerámiákon lehetőségünk volt röntgen-pordiffrakciós (XRD) és lézerablációs induktív csatolású plazma-tömegspektrometriai (LA-ICP-MS) mérések elvégzésére.

A key tenet of Clovis period hunteregatherer mobility is the utilization of large ranges based on the appearance of exotic raw materials, particularly chert, in Clovis assemblages. The identification of the sources of chert in Clovis... more

A key tenet of Clovis period hunteregatherer mobility is the utilization of large ranges based on the appearance of exotic raw materials, particularly chert, in Clovis assemblages. The identification of the sources of chert in Clovis period assemblages is problematic as it has relied on macroscopic properties. Macroscopic characteristics of chert can be highly variable in a single outcrop, occur across very large areas, and have correlates in unrelated and far removed contexts. An instrumental geochemical approach was utilized that potentially offers advances in the capacity to link chert artifacts to their sources. Trace element data was recovered from 33 Clovis period projectile points from the Gault Site (41BL323) using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). This data was compared to trace element data recovered from 224 primary geologic samples of chert from multiple primary sources across the Edwards Plateau in Texas. The Clovis points were compared to the geologic sources using canonical discriminant analysis to establish group membership at three spatial scales: macro-regional (greater than 500 km), regional (between 30 and 500 km), and local (between 1 and 30 km). It was found at the macro-regional scale that 21 of the 33 Clovis points were to be geochemically similar to Edwards Plateau sources. At the regional scale, 15 of the 21 identified Edwards Plateau Clovis points could be attributed to a particular source. Lastly, only two Clovis points could be identified to particular sources at the local scale.

The paper presents newly obtained field and laboratory data for flint raw materials and artefacts from northwestern Bulgaria. The field survey and associated analytical work were carried out in 2020 with the following purposes: i)... more

The paper presents newly obtained field and laboratory data for flint raw materials and artefacts from northwestern Bulgaria. The field survey and associated analytical work were carried out in 2020 with the following purposes: i) identifying flint raw material outcrops in the region; ii) collecting suitable raw material samples from discovered outcrops and flint artefacts from newly excavated archaeological sites; iii) integrated laboratory analyses of the samples (micropetrography and geochemistry); iv) recording and updating information about archaeological sites in the "Archaeological Map of Bulgaria" information system in the Montana and Vidin regions; and v) GIS-based reconstruction (least-cost path models) of possible raw material procurement systems, based on similarities between samples from different archaeological sites and flint outcrops. The micro-petrography and trace elements, determined by LA-ICP-MS suggest that only a few specimens among the analysed artefacts from NW Bulgaria show similarities to the local raw materials. The artefacts sampled as macroscopically similar to the Balkan flint (BF) from the recently discovered Neolithic sites in NW Bulgaria show affinity with previously studied samples of BF from the Pleven-Nikopol region, where two main clusters of BF sources were identified and recorded in 2011. Additionally, GIS-determined pathways of flint distribution are suggested in the context of raw material procurement strategy and acquisition.

Thirteen medieval skeletons excavated from the Museu de Évora (Portugal) cellars were studied through the stable isotopic analysis of carbon and nitrogen ratios in the bones using EA-IRMS (Elemental Analysis - Isotope Ratio Mass... more

Thirteen medieval skeletons excavated from the Museu de Évora (Portugal) cellars were studied through the stable isotopic analysis of carbon and nitrogen ratios in the bones using EA-IRMS (Elemental Analysis - Isotope Ratio Mass Spectrometry) and the trace elements in their tooth enamel and dentine using LA-ICP-MS (Laser Ablation Inductively Coupled Mass Spectrometry) to reconstruct diet and understand social status between and within two distinct populations. Two individuals from the Islamic Period were found to have diets mainly based on C3 plants with some C4 or marine resource influences. The Medieval Christian adults, thought to be an elite order of knights who protected the city after the Reconquest of Portugal, displayed varied diets with mostly C3 plants and high levels of protein, probably marine-based. This supports historical documentation of restricted eating habits within the Order of Évora and also of the diverse origins of the order’s members. The concentrations of Ba and Sr relative to Ca in the tooth enamel were considered as additional paleodietary indicators. The extent of diagenesis was assessed in the bones using ATR-FTIR (Attenuated total reflection- Fourier-transform infrared spectroscopy) to measure crystallinity and collagen content, and collagen quality was assessed by carbon to nitrogen ratios in the elemental analyser. Skeletons from Survey 50 were found to be in a poorer state of preservation than those from the other zones. Diagenetic alteration in the teeth was evaluated with LA-ICP-MS by measuring U and rare earth element (REE) concentrations, and lead ingestion was identified in the enamel of two individual, one being the Muslim adult female and the other a young Medieval Christian adult.

Base glasses from the eastern Mediterranean which circulated in Rome between the fifth and tenth centuries bear witness to the persistence of long-distance trade after the fall of the Western Roman Empire. LA-ICP-MS data of vessel... more

Base glasses from the eastern Mediterranean which circulated in Rome between the fifth and tenth centuries bear witness to the persistence of long-distance trade after the fall of the Western Roman Empire. LA-ICP-MS data of vessel fragments, mosaic tesserae and indicators of production excavated in the Forum of Caesar identify a substantial amount of recycled Roman base glass mixed with later Foy.2.1 glass, flanked by Roman Mn and Sb, Foy 2.1, Foy 3.2, HIMT and Levantine I base glass. Recycled compositions have been documented since the fifth century. Base glasses dating later than the seventh century are completely missing, indicating an interruption or a strong contraction of the commercial flows sometime in the seventh century. The identification of a small number of medieval vessels is coherent with the presence in the area of a dwelling context of elevated status. The compositional features of these glasses reflect the intensification of recycling in the eight century, when the commerce of cullet became increasingly international and some fresh glass continued to travel along the Adriatic trade routes.

The mobility of the Blemmyes between the Nile Valley and the Red Sea coast, and their skill in trading, are well attested in the literary sources and in the archaeological record. While they operated mainly in the Eastern Desert, their... more

The mobility of the Blemmyes between the Nile Valley and the Red Sea coast, and their skill in trading, are well attested in the literary sources and in the archaeological record. While they operated mainly in the Eastern Desert, their cemeteries, dated to the mid-fourth century CE, were located in the strategic region of the Dodekaschoinos of Lower Nubia. The personal adornments of the Blemmyes are mainly composed of beads, but the glass imports have not yet been scientifically studied. This paper presents the results of an analysis of thirty-four glass beads from Blemmyan cemeteries around Kalabsha. Compositional analyses using laser ablation–inductively coupled plasma–mass spectrometry has identified glass belonging to four groups. Numerous glass beads were made from low alumina-soda-lime glass (m-Na-Ca, m/v-Na-Ca), mainly associated with Egyptian production. Five beads were made of high-alumina glass. While three of them were produced in South India/Sri Lanka, mixed or recycled glass was the probable source of high alumina in another two beads. One bead was made of plant ash-soda glass. Results provide scientific evidence for the northernmost presence of South Indian/Sri Lankan glass beads in the Nile Valley and hint at the Blemmyan participation in broader regional exchange networks in Northeast Africa during a time of intensive overseas trade.

Unlike many goods in the eighteenth century, which were wholly imported, utilitarian coarse earthenwares were also produced locally within the American colonies. In the Chesapeake region, it has been suggested that these local wares were... more

Unlike many goods in the eighteenth century, which were wholly imported, utilitarian coarse earthenwares were also produced locally within the American colonies. In the Chesapeake region, it has been suggested that these local wares were primarily reserved for those unable to directly participate in the transatlantic credit economy fostered by the tobacco consignment system. Rather than relying on ambiguous visual attributes to identify these wares, this study utilized elemental analysis via LA-ICP-MS. Coarse earthenwares from domestic plantation contexts of varying social status were assigned to production zones based on shared elemental composition with a reference dataset. This reference dataset incorporated sherds from historic earthenware production sites across the mid-Atlantic and in Great Britain, representing 12 geologically distinct production zones. The results emphasize the diversity of coarse earthenware sources that Chesapeake residents accessed, both local and imported. There was a steady decrease in the use of imported wares in favor of domestically made products over time. There were no sharp differences among plantation households of different statuses, suggesting that these everyday wares were equally accessible to all, perhaps via plantation provisioning strategies. The omnipresence of local wares is evidence for the pragmatic and political strengths of local production.

This article examines the production and exchange of kaolin fine ware ceramics among Recuay communities in highland Ancash, Peru (ca. 100 – 700 CE). We draw upon geochemical (LA-ICP-MS) and petrographic data to investigate raw material... more

This article examines the production and exchange of kaolin fine ware ceramics among Recuay communities in highland Ancash, Peru (ca. 100 – 700 CE). We draw upon geochemical (LA-ICP-MS) and petrographic data to investigate raw material use, provenance, and intraregional trade. We present data on 115 decorated and plain ceramics sampled from nine archaeological sites, which we compare with data on raw kaolin clays. The results indicate a complex network of production and exchange, which included: 1) local production near almost all sites; 2) the limited exchange of ceramic vessels; and 3) the possible distribution of kaolin clay from at least two sources.

The Howard’s Pass district, located in Yukon Territory, comprises 14 Zn-Pb sedimentary exhalative (SEDEX) deposits that collectively contain approximately 400.7 Mt grading at 4.5 % Zn and 1.5 % Pb. Sulfide mineralization is hosted in... more

The Howard’s Pass district, located in Yukon Territory, comprises 14 Zn-Pb sedimentary exhalative (SEDEX) deposits that collectively contain approximately 400.7 Mt grading at 4.5 % Zn and 1.5 % Pb. Sulfide mineralization is hosted in carbonaceous and calcareous to siliceous mudstones. Pyrite is a minor but ubiquitous component. Detailed petrographic analyses reveal that pyrite has a complex and protracted growth history, and multiple generations of pyrite are preserved in single grains. Combined electron probe microanalysis (EPMA) and laser ablation-inductively coupled mass plasma-mass spectrometry (LA-ICP-MS) of paragenetically complex pyrite reveal minor and trace element zonation that mimic textural features. These data provide information on the relative timing and cation content of depositional (i.e., ambient marine), hydrothermal, and metamorphic fluids. These data also identify a suite of nonore elements (Mn, As, Ag, Sb, and Tl) associated with the Zn-Pb mineralizing hydrothermal fluids. Lithogeochemical data and statistical results corroborate the microanalytical findings. These elements are associated with both syngenetic to earliest diagenetic pyrite and later diagenetic pyrite overgrowths, suggesting that SEDEX mineralization was not only the product of hydrothermal precipitates that settled on the seafloor, but also dense metalliferous brine also settled on, and percolated through, unconsolidated carbonaceous muds and precipitated metals. This genetic model is similar to that proposed for the Paleoproterozoic HYC Zn-Pb-Ag SEDEX deposit in northern Australia, and it is likely that common processes and ambient conditions led to the formation and preservation of both of these large SEDEX districts.

This paper reports the results of elemental analysis, using laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS), of 30 glass beads from an assemblage of beads excavated at medieval al-Basra, Morocco. Six chemical... more

This paper reports the results of elemental analysis, using laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS), of 30 glass beads from an assemblage of beads excavated at medieval al-Basra, Morocco. Six chemical glass types are represented and their characteristics and geographical origins are discussed, with reference also to the techniques used to make the beads. The presence of numerous beads of lead–silica glasses is of particular interest. The morphological, technological and chemical analyses of the bead assemblage shed light on al-Basra's trade connections.

Despite many well-known indications suggesting the presence of a flourishing glass production in Aquileia during the Roman age, to date no furnace has ever been identified. In November 2017, during field-walking survey activities part of... more

Despite many well-known indications
suggesting the presence of a flourishing glass
production in Aquileia during the Roman
age, to date no furnace has ever been identified. In November 2017, during field-walking survey activities part of the EC funded
landscape archaeology project Visualising
Engineered Landscape (VEiL), an extraordinary concentration of hundreds of raw glass
chunks and shards of glass was identified on
the surface of a ploughed field in the Northern fringes of the Roman city, just outside
the ancient city walls. Fragments collected
included several chunks encrusted on refractory material (the majority being natural bluegreen, with smaller quantities in blue and olive green), droplets and trails together with
other glass working wastes and fragments of
vessels. This remarkable in situ plough soil
assemblage, clustered in a relatively small
spatial dispersion, may reflect the existence
of a secondary glass workshop. This paper
expands on the satellite imagery analysis and
the field prospections that led to the identification of the archaeological context and the
preliminary outcomes provided by morphological and archaeometric analysis including
Laser Ablation Inductively Coupled Plasma
Mass Spectrometry (LA-ICP-MS) and UVVis Reflectance Spectroscopy carried out on
some of the most relevant samples of glass
recovered. This new discovery could represent a unique opportunity to expand our current understanding of use and consumption
of glass in Roman period in the area and the
broader northern Adriatic context.

A common issue in non-destructive surface analysis of historical silver coins is depletion of Cu from the near-surface areas, which in turn results in higher Ag content at a coin’s surface. This paper reports a non-destructive analytical... more

A common issue in non-destructive surface analysis of historical silver coins is depletion of Cu from the near-surface areas, which in turn results in higher Ag content at a coin’s surface. This paper reports a non-destructive analytical strategy using µXRF for identification of Ag and Cu surface enrichments and depletions by comparing peak intensity ratios of Ag Kα/Ag Lα, Cu Kα/Ag Kα and Cu Lα/Ag Lα for coins and Ag-Cu standards of similar composition. Our characterization of coins from different contexts and chronologies shows that a multi-standard approach provides the most reliable identification of surface enrichment of Ag and depletion of Cu. Coins possessing Ag surface enrichment were further analysed with LA-ICP-MS to determine any differences in trace element composition between the cores and surface of the coins. We show that the near-surface regions of these coins are enriched in Au and depleted in Co, Ni, As, and Pt relative to their cores. These systematics allow for a more robust assessment of the degree of silver coin surface alteration critically important in measuring the original composition of historical silver coins.

The Lamego orogenic gold deposit (440,742oz gold measured reserves and 2.4milliont measured resources, with an average grade of 5.71g/t Au and a cut-off grade of 2.15g/t Au; AngloGold Ashanti Córrego do Sítio Mineração S/A (AGA) personal... more

The Lamego orogenic gold deposit (440,742oz gold measured reserves and 2.4milliont measured resources, with an average grade of 5.71g/t Au and a cut-off grade of 2.15g/t Au; AngloGold Ashanti Córrego do Sítio Mineração S/A (AGA) personal communication, 2014) is located in the 5km-long trend that includes the world-class Cuiabá deposit. It is hosted in the Neoarchean metavolcano–sedimentary rocks of the Rio das Velhas greenstone belt, Quadrilátero Ferrífero, Brazil. Mineralization is associated mainly with metachert–banded iron formation (BIF) and carbonaceous phyllites in the reclined Lamego fold, in which the Cabeça de Pedra orebody represents the hinge zone. Mineralization is concentrated in silicification zones and their quartz veins, as well as in sulfide minerals, product of BIF sulfidation. Hydrothermal alteration varies according to host rock, with abundant sulfide–carbonate in BIF, and sericite–chlorite in carbonaceous phyllite. Quartz vein classification according to structural relationships and host rocks identified three vein systems. The V1 system, mainly composed of smoky quartz (Qtz I) and pyrite, is extensional, crosscuts the bedding plane S0 of BIF, and is parallel to the fold axis. The V2 system, of the same composition, is represented by veins that are parallel to the S1–2 foliation and S0. This system is also characterized by silicification zones in the BIF–carbonaceous phyllite contact that has its maximum expression in the hinge zone of folds. The V3 system has milky quartz (Qtz II) veins, which result from the recrystallization of smoky quartz, located mainly in shear zones and faults; these veins form structures en echelon and vein arrays. The most common ore minerals are pyrite, As-pyrite and arsenopyrite. Fluid inclusion-FI trapped in all quartz veins present composition in the H2O–CO2 ±CH4–NaCl system. Fluid evolution can be interpreted in two stages: i) aqueous–carbonic fluid trapped in Qtz I, of low salinity (~2% equiv. wt.% NaCl), and ii) carbonic–aqueous fluid, of moderate salinity (average 9eq.wt.% NaCl) hosted in Qtz II. Both stages are characterized by decrepitation temperatures in the range of 200 to >300°C, and suggest a fluid of metamorphic origin. Applying an arsenopyrite geothermometer, the calculated formation temperature for the Cabeça de Pedra orebody is 300 to 375°C. The vertical intersection of the isochors allows a minimum pressure calculation of 2.6kbar. The composition of individual FIs of this orebody, obtained by LA-ICP-MS analyses, compared with results of FIs for the Carvoaria Velha deposit, Córrego do Sítio lineament, highlights a standard composition typical of metamorphic fluids with Na>K>Ca>Mg, which increase or decrease in concentration as a function of salinity in both deposits. Trace elements vary according to fluid–rock reactions, and are directly related to the host rock composition. The comparison of data sets of the two deposits shows that the Cabeça de Pedra FIs have a higher enrichment in Zn, while Cu, As and Sb are richer in Carvoaria Velha, suggesting influence of the host rock geochemistry. The suggested mechanisms for gold precipitation at the Cabeça de Pedra orebody, Lamego gold deposit are: i) hydrolysis of the carbonaceous matter of phyllite and BIF, affecting fO2, destabilizing sulfur complexes and enhancing gold precipitation; ii) replacement of BIF iron carbonates by sulfides; and iii) continuous pressure changes that lead to silica precipitation and free gold. Other than playing the long-recognized role of the carbonaceous phyllites as a fluid barrier, the data highlight their importance as a source of metals.

Modern archaeology makes use of analytical methods in order to answer questions about deposit and technological provenience of artefacts. This paper discusses selected and the most interesting, results obtained during the completion of a... more

Modern archaeology makes use of analytical methods in order to answer questions about deposit and technological provenience of artefacts. This paper discusses selected and the most interesting, results obtained during the completion of a research project which focuses on silver from the 10th and 11th centuries in Poland. In total, 200 silver artefacts known from Polish hoards (found in Kalisz-Dobrzec, Nowa Obra, Wolsztyn District, Zalesie, Olsztyn District, Słuszków and Jastrzębniki, Kalisz District, Kalisz-Rajsków and Stojkowo, Kołobrzeg District and Naruszewo, Płońsk District) were studied. A micro-invasion LA-ICP-MS (Laser Inductively Coupled Plasma Mass Spectrometry) was used for determinining lead isotope ratios in silver. The data obtained were evaluated using statistical methods which allowed reliable isotopic ratios in inhomogeneous alloy to be obtained. In order to study the provenance of silver, the obtained lead isotope ratios in the artefacts were compared with those of silver deposits. The use of SEM-EDX allowed the tracing of morphological changes and the measurement of quantitative elemental composition of coins, raw silver and jewellery according to technological traits. KEYWORDS: Silver in medieval Poland, SEM-EDX, LA-ICP-MS, lead isotope ratio analyses, statistical models.

Life science collections and their curated metadata are now seen as potential archives of environmental levels of trace elements. Bird feathers are especially promising material, but surface contamination might present a significant... more

Life science collections and their curated metadata are now seen as potential archives of environmental levels of trace elements. Bird feathers are especially promising material, but surface contamination might present a significant issue. The suitability of preserved specimens for environmental studies may be further limited by historical application of inorganic pesticides in the collections. Arsenic (As) and mercury (Hg) are the most significant inorganic contaminants in natural history collections since they were widely applied as pesticides from the late 18th century until the 1980s. Potential presence of As-and Hg-containing pesticide residues has also to be taken into account when members of the public are allowed to handle specimens. Even though the testing of taxi-dermy and anthropology museum collections for pesticide residues is becoming a common practice, it is generally done qualitatively rather than quantitatively. In this study, the concentrations of As and Hg were determined in feathers of eleven bird specimens considered for an interactive display and were found to range from 1.1 to 15,183 μg g −1 and from b 1 to 26,960 μg g −1 , respectively. The study shows how the quantitative information can be obtained and the history of the pesticide treatment reconstructed using a combination of analytical techniques including bulk analysis by inductively coupled plasma mass spectrometry (ICP-MS) following destructive or non-destructive sampling, and spatially resolved techniques such as laser ablation (LA)-ICP-MS and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). Inorganic As speciation by squarewave anodic stripping voltammetry (SWASV) and localisation of pesticide residues by X-ray micro-computed tomog-raphy (μCT) can provide additional information. It is found that As is not only present as micron-sized particulate residues, but becomes incorporated into the keratin matrix of the feathers. Mercury is probably nano-particulate and fully incorporated into keratin. The history of pesticide treatment might be complicated with mixtures of chemicals involving both As and Hg compounds and more than one way of pesticide application used on the same specimen.

The Late Prehistoric period of the central Illinois River valley (CIRV) is perhaps best known from the high levels of conflict and violence seen in burial and cemetery contexts. Yet, comparatively little is known about the social context... more

The Late Prehistoric period of the central Illinois River valley (CIRV) is perhaps best known from the high levels of conflict and violence seen in burial and cemetery contexts. Yet, comparatively little is known about the social context of these violent interactions. This poster presents the results of a pilot study designed to determine whether laser ablation inductively couple plasma mass spectrometry (LA-ICP-MS) can generate data from which meaningful ceramic and clay compositional groupings can be created in the CIRV. Results suggest that LA-ICP-MS is able to create meaningful groupings, and will allow questions about regional mobility to be explored.

Native American inhabitants in the interior Southeast did not experience direct and prolonged European contact until the late 1600s, however European trade goods still managed to filter their way into the area. While trade goods are... more

Native American inhabitants in the interior Southeast did not experience direct and prolonged European contact until the late 1600s, however European trade goods still managed to filter their way into the area. While trade goods are present, site chronology has not been clearly defined in many areas. Both pXRF and LA-ICP-MS testing on 282 glass trade beads from East Tennessee and surrounding states has revealed trends in their chemical composition which can be correlated to date ranges. This method of analysis allows us to answer questions about Native American habitation in East Tennessee during the Protohistoric Period.

This research focuses on advancing chert sourcing using non-destructive LA-ICP-MS to characterize chert resources within the Edwards Plateau through combination of in-depth testing of inter- and intra-formation chert variability. Three... more

This research focuses on advancing chert sourcing using non-destructive LA-ICP-MS to characterize chert resources within the Edwards Plateau through combination of in-depth testing of inter- and intra-formation chert variability. Three chert bearing Early Cretaceous Edwards Limestone formations were identified, classified, and distinguished through geochemical composition to document inter- and intra-formation variability. The three primary geologic areas (Callahan Divide, Fort Hood, and Leon Creek) of the Edwards Plateau were analyzed and compared with Clovis period artifacts, also analyzed using LA-ICP-MS, from the Gault site. The Gault site is an important multi-function archaeological site with rich deposits of Clovis artifacts.