Lead Isotope Analysis Research Articles

Lead isotope analysis of native copper deposits in the Lake Superior Basin

AbstractThis paper is a pilot study using lead isotope analysis to source native copper in the Lake Superior Basin. Forty Pb isotope samples are sampled from native copper deposits across the Lake Superior Basin and analyzed via MC‐ICP‐MS at Indiana University's Metal Isotope Lab. The result of this analysis demonstrates that there is a significant overlap between Pb signatures of native copper sources within the Lake Superior Basin. As a result, lead isotope analysis is not recommended as an alternative for sourcing native copper within the Lake Superior Basin.

New Archaeometallurgical Fingerprints of Copper and Slag from Early Iron Age Smelting Sites in Faynan and Timna

The copper deposits of Faynan and Timna have been exploited in two major economic cycles: a Chalcolithic – Early Bronze Age cycle, and a Late Bronze Age – Early Iron Age cycle. The present study focuses on the Late Bronze Age - Early Iron Age cycle of the two districts and analyses a relatively large sample of smelting remains from their main smelting sites (slag, raw copper, archaeological ores). The analytical results from lead isotope analysis (LIA; n = 145), copper isotope analysis (CIA; n = 49), chemical analysis (n = 52) and microstructural analysis (n = 5) are compared with the current geological and mining archaeological knowledge and confirm earlier results according to which in Faynan only the ore type DLS was smelted in this phase and in Timna almost exclusively the ore type Amir/Avrona. Based on the analytical data, multidimensional models of these two copper types are developed, which presumably come relatively close to the copper types marketed in reality. Our models are intended to serve as a basis for comparison in future provenance studies.

Lead isotopic compositions link copper axes from Kietrz (Poland, 3500–3350 BC) to Slovak and Balkan copper mines

AbstractChemical and lead isotope analyses aided by metallographic examination of copper axes found at the Late Neolithic settlement of Kietrz in southwestern Poland provide new evidence for the origin of copper and metal trade routes in the region. Our results indicate that metal used for the axes could be sourced from copper mines in modern Slovakia, Bulgaria and perhaps Serbia. The evidence from this study confirms that the Funnel Beaker people from Poland became parties to a metal trading network that connected much of continental Europe in the mid‐4th millennium bce and provides a better understanding of how these contacts provided the background for the technological and socio‐economic developments of the Baden era.

Darkening of lead white in old master drawings and historic prints: A multi-analytical investigation

Old master drawings and historic prints often feature white highlights, which are typically painted using lead white, one of the most widely used historical white pigments. However, it has been observed that many of these highlights discolour over time, becoming dark brown or black due to unclear degradation processes. This phenomenon not only misrepresents the original artefacts, threatening their suitability for public display, but also diminishes their longevity. To ensure their preservation, it is essential to determine why some lead white highlights in these museum objects retain their light tones while others are prone to darkening. The objective of this study was to identify the relationships between the composition, provenance, and production methods of lead white pigments, and their role in the discolouration observed on drawings, lithographs and early photographs. Selected samples and artefacts were examined using a range of analytical techniques, namely X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRPD), and lead isotope analysis. While XRF analyses confirmed the presence of lead as the primary element in the majority of the highlights, XRPD measurements identified a variety of lead compounds such as the carbonates cerussite and hydrocerussite alongside galena—a black crystalline sulfide—and lead sulfates. Additionally, isotope analyses classified the lead raw materials into five main groups. Through these measurements, the examined lead white pigments were categorised based on their compositional properties in relation to the raw materials used, as well as their geographical and temporal origin. A significant finding is that lead white pigments from different production periods, spanning from older to more modern, may be characterised by varying proneness to discolouration irrespective of their provenance.

SIRET REVISADO: LOS METALES DE LA COLECCIÓN SIRET DEL MUSEO BRITÁNICO

This paper presents the analytical study of the metal objects from the Siret Collection held by the British Museum. X-ray Fluorescence has been conducted to determine their elemental composition and by lead isotope analysis (by MC-ICP-MS) to determine their origin. We combine this new data with extant analyses to discuss and reinterpret the role of bronze alloys in Argaric society and the diversity of exploited mining resources.

ANÁLISE DE FRAGMENTOS BALÍSTICOS POR MEIO DE EXAMES MICRO BALÍSTICOS, DETERMINAÇÃO DA COMPOSIÇÃO QUÍMICA E ANÁLISE ISOTÓPICA DO CHUMBO: UMA REVISÃO

BALLISTIC FRAGMENTS ANALYSIS BY MICRO BALLISTIC EXAMINATIONS, CHEMICAL COMPOSITION AND LEAD ISOTOPE RATIOS: A REVIEW. Firearms and ammunition identification produces important information for the elucidation of the crime and also in cases of confirmation of the offender. In a crime scene, when a suspect weapon and its ammunition are found, it is possible to clarify and conclude an investigation using qualitative analysis and standards. However, in some cases only the fragments of ammunition are found, which makes difficult to identify the weapon using traditional techniques. Therefore, alternative methods are needed such as the determination of elemental composition of the lead alloy and the verification of the lead isotopic ratios. The present work includes a review of the basic concepts of ballistics and conventional techniques of ballistic confrontation, the existing studies related to the chemical analysis of ballistic fragments and its application in criminalistics and, finally, the articles involving the lead isotopic analysis as a tool for ballistic identification.

Source identification and risk assessment of trace metals in surface sediment of China Sea by combining APCA-MLR receptor model and lead isotope analysis

This study aimed to investigate the distribution, pollution, risk and sources of trace metals in sediments along China Sea. Clear spatial variations were found for Cr, Mn, Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, and Pb, whereas As did not show spatial variation. East China Sea (ECS) contained the highest concentrations of Mn, Co, Ni, Cu, Zn, South China Sea (SCS) shallow sea contained the highest concentrations of Zn, Se, Mo, Ag, Cd, and Pb, whereas coral reefs contained the lowest concentrations of trace metals. Spatial variations could be explained by economic development characteristics along China Sea. As, Se and Cd exhibited low to moderate pollution in China Sea sediment, yet pollution for Cu, Zn, Ni, and Ag appeared in some regions. Sediment in ECS had moderate ecological risks and other regions at low ecological risks. The absolute principle component score-multiple linear regression (APCS-MLR) and Pb stable isotope indicated that 43–74% of trace metals (Ni, Cu, Zn, As, Se, Cd, and Pb) were derived from anthropogenic sources like traffic emission, agricultural activities, industrial source. No pollution and ecological risk were observed in coral reefs, yet 39–71% (Pb) was derived from anthropogenic activities such as motor vessels.

Isotopic Analysis of Lead at Ultratrace Levels Using Thermal Ionization Mass Spectrometry (TIMS) Coupled with the Continuous Heating Method: Optimization of the Data Integration Range and Method.

This study systematically and experimentally evaluates data integration methods for the isotopic analysis of Pb at ultratrace levels using thermal ionization mass spectrometry (TIMS) with a continuous heating method. The evaluation utilized a certified reference material of Pb (SRM 981). The experimental evaluations encompass different data calculation methods (methods I, II, and III) and integration ranges (full, over 1%, 25%, and 75%). Method I, in which isotope ratios were calculated based on summed ion signal intensities compensating for mass fractionation, was consistent with the certified values for 10 and 1 ng standard samples across all integration ranges. For 100 pg samples, full range calculations failed for specific isotope ratios, but reduced ranges (over 1%, 25%, and 75%) yielded values overlapping with certified ones. Method II, in which isotope ratios were calculated by averaging the precalculated isotope ratios, exhibited inferior performance compared to method I. Method III, using weighted averaging to reduce anomalous values, showed results consistent with those of method I but was recommended only for single measurements. An integration range of over 1% or 25% is preferred to exclude anomalies while compensating for mass fractionation. The optimized method was validated by comparing two different instruments used for the isotopic analysis of the reference material. The enhanced accuracy and precision provide valuable insights for researchers working in ultratrace-level Pb isotopic analysis using TIMS.

Sources of early Islamic silver: lead isotope analysis of dirhams

The expansion of the early Islamic state (c. AD 700–900) was underpinned by the minting of silver coins (dirhams) on an enormous scale. While the wider effects of this coinage have been studied extensively, the sources of silver have attracted less attention and research has relied on literary texts pointing to mines in Arabia and Central Asia. Here, the authors use lead isotope and trace element analyses of more than 100 precisely dated silver coins to provide a geochemical perspective on Islamic silver. The results identify multiple new sources, stretching from Morocco to the Tien Shen, and indicate an Abbasid-period mining boom. These source locations have implications for contemporary geopolitics including on the Islamic-Byzantine frontier.

Exotic treasures or local innovation: Gold and silver beads of han dynasty excavated from Nanyang City, Henan Province, central China

The emergence and utilization of gold beads in China were influenced by foreign civilizations and cultures, while the exploration of composite beads in China has been relatively limited compared to single-material beads. Metal foil glass beads represent a distinct type of composite beadwork popular in ancient times. This paper presents findings from a study conducted on a group of beads that were unearthed in Nanyang City, Henan Province. Theoretical calculations and CT imaging suggested that a particular class of gold beads, previously misidentified as single-material beads, actually consisted of gold foil wrapped around an inner layer of glass beads. Elemental analysis techniques such as pXRF, SEM and μ-EDXRF were used to reveal that the purity of the gold foil of the two differently shaped beads is around 95% and 98.5%, while the silver foil of the silver beads is also around 85% due to corrosion. Microscopic observation confirmed that the gold leaf was applied through foil-fusion gilding. Lead isotope analysis indicated that the gold beads originated from different sources, whereas the silver beads likely originated from the Central Plains region. Furthermore, the evidence of beadwork from Southeast Asia and South China supports the view that the gold beads may have been originally exotic but gradually adaptated through indigenous learning, allowing the creation of high-quality imitations. This study emphasizes the importance of scientific analyses for the proper determination of bead types and craftsmanship, and contributes to a better understanding of the ancient bead circulation network.

Copper-alloy belt fittings and elite networking in Early Medieval Central Europe

This paper attempts to change the traditional view of the Late Avar belt fittings, which in the 8th century AD delineated an extremely dense communication network within the Carpathian Basin and beyond, by using a groundbreaking combination of iconography, energy dispersive X-ray fluorescence (EDXRF), scanning electron microscopy (SEM), lead isotope analysis, digital morphometry and 3D comparative prototyping. It presents a complex analysis of bronze belt ends decorated with an exceptional scene of a snake eating a frog-like creature, discovered in the last decade in Czech Republic, Hungary and Germany. According to the iconography, this motif represents an important cosmogonic and fertility myth, known to various early medieval populations living in Central Europe. Some of these belt ends come from the same workshop and/or are derived from a common model, even though they were found in very distant regions. The study also focuses on the provenance of the raw material used in the production of Avar-style belt fittings in general. For the first time, it was possible to locate the Early Medieval source of copper in the Slovak Ore Mountains, using lead isotope analysis.

Travel of faience beads and metal Pins: Evidence of long-distance trade in early Bronze Age I (3100–2900 BCE) Başur Höyük, Türkiye

This paper presents the compositional results of one stone and six faience beads together with five metal pin fragments from Başur Höyük, southeast Türkiye in order to preliminarily evaluate possible source and production regions. Dating to the Early Bronze Age I (ca. 3100–2900 BCE), the samples are part of burial contexts with more than 100,000 beads, hundreds of metal objects, and evidence of human sacrifice. The microstructures of blue and greenish-blue faience beads indicate the application of cementation and efflorescence techniques. The variations in mineral compositions and differences in production techniques of the faience beads indicate Başur Höyük’s access to at least two production centers for faience beads. Pins were made of copper and arsenical copper. Lead isotope analysis on metals indicates possible ties to Iran. Evaluated with further archaeological data from the site, consumption of copper from the Kerman and Sistan regions demonstrate the earliest evidence of the long-distance trade of southeast Anatolia with southeast Iran feasibly via southern Mesopotamian or Diyala region networks. This indicates considerable connectivity and organization in the aftermath of the Uruk collapse and shows both sophisticated technical knowledge and shared aesthetic values between regions.

Lead isotope ratio analysis of lead ingots and bronze wares unearthed from Yinxu

AbstractThis study gives the element compositions and Pb isotope ratios of three lead ingots and three bronze artefacts unearthed from Yinxu, Anyang, Henan province, and two lead vessels from Zhengxiaozhuang tomb, Anhui province, China. The results of composition analysis show that three lead ingots in Yinxu may be the primary product of lead smelting. The lead wares unearthed in Zhengxiaozhuang tomb could be a kind of Mingqi‐funerary replicas. The results of Pb isotope analysis indicate that the culture exchanges between the Central Plains and the Jianghuai area in the late Shang dynasty. The decrease of bronzes with the highly radiogenic lead is consistent with the increase of Pb content in Yinxu bronzes simultaneously, which could be related to the change of lead source.

A multi analytical characterization of a small bronze figurine from Gran Carro site (Bolsena Lake, Italy)

This paper presents the results of an archaeometric analysis carried out on an early Iron Age anthropomorphic figurine discovered in the area of the Gran Carro on Bolsena Lake (Latium, Italy) site, currently interpreted as a place of worship. This statuette is considered a unicum, both because of the context in which it was found and because of its stylistic characteristics similar to those of bronzes from the Nuragic civilization (Sardinia, Italy). Its discovery and the data obtained from this work provide further evidence in support of numerous previous studies suggesting the presence of trade and direct exchanges between Sardinia and southern Etruria. The research was performed through some non-destructive investigations such as Energy Dispersive X-Ray Fluorescence (EDXRF) combined with Monte Carlo Simulation (MC) and micro-invasive investigations such as Scanning Electron Microscopy coupled by Energy Dispersive Spectroscopy (SEM–EDS) and by Electron Probe Micro-Analysis (EPMA), metallography and lead isotope analyses (LIA), performed on a selected micro-fragment. The combination of non-destructive techniques (EDXRF-MCS) for the characterization of the artefact allowed us to obtain data similar to those obtained with micro-invasive surveys, further demonstrating the effectiveness of the method. The results indicate that the statuette is made of a bronze alloy and that the copper metal was extracted from Sardinian deposits.

A feast: Indigenous production and interregional exchange reflected by the bronze vessels unearthed from Shuangyuan Village Cemetery in southwestern China

AbstractSurprising combinations of bronze vessels with multiple cultural elements have been unearthed in Shu tombs in southwestern China, indicating a significant connection with the middle and lower reaches of the Yangtze River. However, there is currently no comprehensive evidence for the provenance of these foreign style vessels, and little emphasis has been given to the diachronic changes in the interaction between Shu culture and its surroundings. This article investigates the bronze vessels unearthed from the Shuangyuan Village Cemetery in Chengdu during the Eastern Zhou Dynasty and aims to deeply reveal the production and exchange of bronze vessels unearthed from Shuangyuan Village Cemetery from the perspective of lead sources through typological analysis and scientific analysis. The study clarified the ages of the local style Shu culture vessels and foreign style vessels, and the latter exhibited a strong influence of the Chu and Yue cultures. Lead isotope analysis shows that the lead source characteristics of foreign style vessels are consistent with those of vessels from Chu‐Yue culture at the same time, and they may be imported from Chu directly. The specific interaction modes of Shu and Chu underwent a clear transformation during the middle Warring States period.

AMALIA, A Matching Algorithm for Lead Isotope Analyses: Formulation and proof of concept at the Roman foundry of Fuente Spitz (Jaén, Spain)

This article presents A Matching Algorithm for Lead Isotope Analyses (AMALIA) that yields analytical coincidences in lead isotope databases, allowing a fast selection of potential candidates for metal provenance. As a proof of concept, potential ore sources for 29 Roman lead artifacts from the archaeological site of Fuente Spitz (Jaén, Spain) are provided. Additionally, a reassessment of legacy, TIMS lead-isotope analyses is conducted by re-analysis of 26 galena samples from nearby mining districts by MC-ICP-MS. The study demonstrates the accuracy and reliability of AMALIA and stresses the need to assess the isotope ratio data obtained without lead isotopic tracers (spikes) by TIMS carefully on a case-to-case basis. At the archaeological level, our study shows that the foundries and smelting sites at Fuente Spitz and Cerro del Plomo processed galena ores from the mining districts of La Carolina and Linares to produce a variety of lead products and lead ingots that have been found at several places thorough Europe, thereby providing tangible evidence of the regional and long-distance commercial circuits that these foundries were supplying.

Petrographic and lead isotope analyses to assess regional variability in Rio Grande Glaze wares from New Mexico

The broad spatial distribution and long period of production of Rio Grande Glaze Ware vessels hides considerable material diversity within the typological grouping as a ware. This has long made archaeometric techniques attractive options for understanding variability within the Rio Grande Glaze Ware category. We present the results of new petrographic analysis of Rio Grande Glaze Ware pastes and new isotopic analysis of Rio Grande Glaze Ware glaze paint. The results of these new analyses complement extensive earlier work characterizing both Rio Grande Glaze Ware pastes and paint. Especially relevant is the identification of glaze paints made primarily with lead ores from the Hansonburg district or made by mixing Hansonburg ore with the more commonly used Cerrillos district ores. The predominant use of Cerrillos ore in the production of lead glaze paint identified in prior work is nuanced through the additional data presented here, which suggests a division in networks of lead ore and/or glaze paint procurement between a larger, northern network making use of Cerrillos ores, and a smaller, southern network relying on Hansonburg ores for glaze paint production.

Genesis of the Hatu gold deposit: Constrained by in situ S[sbnd]Pb isotope geochemistry of pyrite

As the largest gold deposit in west Junggar, the Hatu gold deposit is located between the Anqi and Hatu faults in the Hatu-Sartohay district. The orebodies, composed of gold-bearing quartz veins and auriferous altered wall-rocks, are controlled by NE-, NW-, and EW-trending faults in Early Carboniferous volcano-sedimentary rocks. In this study, integrated textural, in situ sulfur and lead isotope analyses of pyrite grains in the host rocks and ores reveal new information on the sources of the ore-forming fluids and metal, as well as the mechanism of gold deposition. Framboidal pyrite in tuffaceous siltstone has a large δ34S range of −26.7 to +54.0 ‰, which is attributed to sulfur-reducing bacterial (SRB) activity during sedimentary-diagenetic process. Fine-grained subhedral pyrite in meta-basalt shows negative δ34S values from −26.7 to −12.1 ‰, which may be generated by reduction of seawater sulfate by ferrous iron bearing minerals during metamorphism. The δ34S values of four generations of hydrothermal pyrite (Py1–Py4) in the orebodies vary in a narrow range from +1.4 to −1.9 ‰. The sulfur isotopic characteristics of the hydrothermal pyrite are similar to most magmatic hydrothermal deposits, but differ from the metamorphic pyrite in meta-basalt and the framboidal pyrite in tuffaceous siltstone. In addition, the uniform in situ lead isotope ratios of hydrothermal pyrite resemble the lead isotopic compositions of the granitic plutons in the west Junggar, but differ from those of pyrite in meta-basalt. The progressive decrease of δ34S values from early-stage pyrite (+0.7 ‰ to +1.4 ‰) to late-stage pyrite (−1.9 ‰ to +0.4 ‰) corresponds to the major gold precipitation processes, which can be explained by gradual decrease of oxygen fugacity and increase of pH with decrease of temperature of a gold-bearing magmatic-hydrothermal system. A relatively stable environment for Au precipitation probably is a key factor controlling the scale of gold deposit, as the ore-forming fluid has enough time to form large gold deposit such the Hatu gold deposit.

Early mediaeval lead glass bangles from Czermno, Poland: Results of elemental and lead isotopes analyses

AbstractThis paper presents the results from analysis of thirty 12th to 13th century glass bangles from Czermno, eastern Poland. Study of the primary glass composition was carried out by laser ablation ICP‐MS and electron probe microanalysis. Lead isotope analyses were conducted to determine the origin of the glass's main raw material. Two types of lead glass were distinguished, high‐lead glass and Slavic lead ash glass, both of which were common in Central and Eastern Europe in the early Middle Ages. Isotopic investigations show that the lead flux for the Slavic glass likely came from the Cracow–Upper Silesia region in southern Poland.

The Historic Built Environment As a Long-Term Geochemical Archive: Telling the Time on the Urban "Pollution Clock".

This study introduces a novel methodology for utilizing historic built environments as reliable long-term geochemical archives, addressing a gap in the reconstruction of past anthropogenic pollution levels in urban settings. For the first time, we employ high-resolution laser ablation mass spectrometry for lead isotope (206Pb/207Pb and 208Pb/206Pb) analysis on 350-year-old black crust stratigraphies found on historic built structures, providing insights into past air pollution signatures. Our findings reveal a gradual shift in the crust stratigraphy toward lower 206Pb/207Pb and higher 208Pb/206Pb isotope ratios from the older to the younger layers, indicating changes in lead sources over time. Mass balance analysis of the isotope data shows black crust layers formed since 1669 primarily contain over 90% Pb from coal burning, while other lead sources from a set of modern pollution including but not limited to leaded gasoline (introduced after 1920) become dominant (up to 60%) from 1875 onward. In contrast to global archives such as ice cores that provide integrated signals of long-distance pollution, our study contributes to a deeper understanding of localized pollution levels, specifically in urban settings. Our approach complements multiple sources of evidence, enhancing our understanding of air pollution dynamics and trends, and the impact of human activities on urban environments.