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While there is a considerable body of data regarding the sources of minerals employed in Bronze Age Egypt, the supply chains to Sudanese Lower Nubia are virtually unknown. This paper presents results of lead isotope analysis of 11 samples of kohl from C-group, Pan-grave and New Kingdom funerary contexts across the Debeira and Ashkeit areas in Sudanese Lower Nubia during the Bronze Age. The samples could be divided in two groups based on their lead isotope ratios. A comparison between the kohl samples from Sudanese Lower Nubia and galena ores from various mining sites on the Red Sea coast of Egypt indicated that some of the galena used in kohl mixtures in Sudanese Lower Nubia came from the Pharaonic mining site of Gebel el-Zeit. The second group of Nubian samples seems to have originated from an alternative galena source yet to be determined. This is the first time that kohl samples from Sudanese Lower Nubia are integrated into known northeast African networks of supply by using Lead isotope analysis. [ABSTRACT FROM AUTHOR]

Background/Objectives: The management of differentiated thyroid cancer (DTC) patients has undergone a major paradigm shift in past years, especially regarding the role of a careful postoperative disease assessment both in deciding for or against the use of iodine-131 therapy (i.e., patients' selection) and in selecting the correct goal of the treatment: ablative, adjuvant or therapeutic. Furthermore, diagnostic and risk-oriented uses of iodine isotopes (i.e., 123/124/131I) should always be considered during both postoperative assessment and follow-up of DTC patients to improve early staging and response assessment to initial treatments, respectively. The present review summarizes current (and real-life-related) evidence and the emerging perspectives on the therapeutic, diagnostic, and theragnostic use of radioiodine isotopes. Methods: A review of the pertinent literature was performed in PubMed, Web of Science, and Scopus without language restrictions or time limits and using one or more fitting search criteria and terms. Results: According to the literature evidence and real-life clinical practice, a risk-oriented postoperative iodine-131 therapy remains pivotal for most DTC patients and improves early disease staging through post-therapy functional imaging (i.e., theragnostic aim). Accordingly, the goal of iodine-131 therapy, the optimal strategy (empiric vs. dosimetric approach), the appropriate stimulation method [i.e., levothyroxine (L-T4) withdrawal vs. recombinant human thyrotropin (rhTSH) administration] and, finally, the suggested radioiodine activity to deliver for iodine-131 therapy (RIT) should be personalized, especially in metastatic DTC patients. Conclusions: The evidence related to the diagnostic and theragnostic use of iodine isotopes leads to a significant improvement in the postoperative risk stratification and staging of DTC patients in addition to a more accurate assessment of the response to initial treatments. In conclusion, radioiodine is really an oldie but goldie radiotracer. It has both a current fundamental role and a future perspective for the more careful management of DTC patients. [ABSTRACT FROM AUTHOR]

The stable isotope analysis of black powder (BP) is of great significance for its comparison and source inference. Previous studies have verified the feasibility of distinguishing different BP samples through stable isotopes. However, the impact of raw materials and synthesis processes on the stable isotopes of BP remains unclear. On the one hand, the raw materials of BP are widely sourced, and whether stable isotopes can distinguish different source materials remains to be studied. On the other hand, the synthesis of BP involves the physical mixing of raw materials, and whether this process leads to isotope fractionation also needs further investigation. To address these problems, stable isotope ratios of 27 charcoals, 15 potassium nitrates, 6 self‐made and 10 commercial BP samples were analyzed. The results showed that the stable isotope ratios can be utilized to distinguish charcoals and potassium nitrates from different manufacturers and batches. No significant differences in the nitrogen and oxygen stable isotope ratios between the self‐made BP and its raw materials were observed, indicating that the physical mixing process does not induce significant fractionation of stable isotopes. However, the carbon stable isotope ratios of charcoal increased (within 2SD) after being synthesized into BP. Due to the utilization of additives and variations in the synthesis process, the correlation between the stable isotope ratios of commercial BP and its raw materials was complex. The findings of this study provide a scientific reference for tracing the source of BP. [ABSTRACT FROM AUTHOR]

Lead (Pb) poisoning is a significant threat to Aotearoa New Zealand's endangered kea (Nestor notabilis), an avian species important to Māori. Historically, exposure was thought to be from lead‐containing building materials; however, recent field observations suggest lead‐based ammunition as an additional source. We used stable lead isotopes to investigate the sources of lead to kea. Comparing 207 Pb/206 Pb ratios in kea blood (n = 91) to both ammunition and building materials, we found approximately one‐third of exposed kea (blood lead > 10 µg/dL) had lead isotope ratios consistent with exposure to lead‐based ammunition. As lead ammunition is still used, including in government‐sponsored culling programs, our data indicate an urgent need to shift toward non‐lead ammunition use to prevent further poisoning and aid conservation efforts. Collaborating with tangata whenua/Māori guardians, we advocate for immediate policy changes to eliminate lead‐based ammunition in kea habitat to safeguard this endangered culturally treasured species from extinction. [ABSTRACT FROM AUTHOR]

We report three U–Pb sulfate ages from the recently identified Intra-PQ Thrust within the Phyllite–Quartzite (PQ) Nappe of the Ionian high-pressure belt of the external Hellenides in the eastern Mediterranean. Crosscutting relations show that a distinct pressure-solution laminae/microlithon fabric is the oldest deformation structure. Two analyses of sulfate minerals that are part of this structure yielded indistinguishable dates, with a weighted average of 20.03 ± 5.96 Ma. The crosscutting fabric with alteration halos of the sulfate provided a date of 9.37 ± 4.64 Ma. The initial 207Pb/206Pb ratios are ~ 0.40 and thus distinctively lower than the terrestrial model lead isotope ratio of 0.84 for the calculated ages. This can only be explained if the dated sulfate precipitated from a fluid enriched in radiogenic 206Pb, probably sourced by the surrounding country rock through (partial) dissolution of older U-rich minerals. The dates of ~ 20 Ma agree with recently reported fault-gouge ages of 26–21 Ma from the Intra-PQ Thrust. The study demonstrates, for the first time, the possibility of dating sulfate minerals in metamorphosed rocks applying the U–Pb system. [ABSTRACT FROM AUTHOR]

The Xinjiazui gold deposit marks a notable significance in prospecting within the Back-Longmenshan tectonic belt, located on the northwest margin of the Yangtze Block, China. Despite the extensive studies conducted on this deposit, the source of the ore-forming materials remains unclear, leading to ongoing debates regarding the genesis of this deposit. This study analyzed in situ (EPMA and LA-ICP-MS) trace elements and S-Pb isotopes of arsenopyrite, solely from the principal metallogenic stage and paragenetic with native gold. The results show that the gold in arsenopyrite occurs as invisible gold (Au3+), with an average concentration of 9.38 ppm, whereas the concentrations of magma-related elements, such as W, Sn, Mo, and Bi, are very low. The sulfur isotopes (34S) of arsenopyrite range from 8.32‰ to 10.16‰, aligning closely with the deep metamorphic basement (Pt3l). Meanwhile, the lead isotopes in arsenopyrite display characteristics typical of those found in orogenic belts. A comprehensive analysis of the abundance of gold indicated that the metallogenic materials (sulfur and gold) primarily originated from Pt3l. Additionally, the arsenopyrite thermobarometer indicated that the Xinjiazui gold deposit formed in a medium–low-temperature, medium metallogenic environment (5.57–8.69 km), with a sulfur fugacity (log f (S2)) below −8.4. Combined with previous research results, this study proposes that the Xinjiazui gold deposit is a subduction-related mesozonal orogenic gold deposit. In gold prospecting and exploration in the Back-Longmenshan tectonic belt, it is essential to focus on the distribution of brittle-ductile shear zones and location of the quartz veins associated with pyrite and arsenopyrite mineralization. [ABSTRACT FROM AUTHOR]

The Eastern Zhou period of China, characterised by complex interactions among vassal states, witnessed significant advancements in bronze production technology. However, the investigation of interactions based on technological comparison among dominant and dependent states remains limited. Focusing on two newly excavated foundry sites, Baidian in Houma, Shanxi, and Xincun in Hebi, Henan, this study provides crucial insights into the bronze production technologies and material sources used by Jin, a major vassal state in Central China, and Wei, a dependent state of Jin, during the Eastern Zhou period. Elemental analysis and microstructural examinations of slags, fragments of crucible wall and furnace wall, show the diversity of bronze production techniques between these two sites: in the Baidian site, bronzes were predominantly produced by co-melting of metallic copper and tin, and remelting of recycled bronzes, whereas in the Xincun site, bronze were probably made by co-melting of copper and tin ore. Furthermore, lead isotope analysis results suggest that the lead materials used for the bronze production at both the sites were likely from the Xiaoqinling region. Integrated with the historical background of complex interactions among vassal states, these findings not only shed light on the technological advancements and resource networks of the Jin and Wei states but also explain the relationships between technology, resources and social dynamics from various perspective. Hopefully this research would promote archeometallurgical study among regions and be applied to other Bronze Age cultures in the world. [ABSTRACT FROM AUTHOR]

ABSTRACT Laurentia (ancestral North America) records nearly 4 billion years of crustal evolution. Here, a newly compiled continental‐scale Pb isotopic database is used to evaluate the Precambrian crustal evolution of Laurentia. Pb model ages yield a 2.7 Ga peak, a 2.5–1.8 Ga minimum and 1.8–0.9 Ga continuum. Pb model ages yield thermochronometric data and track crustal growth via arc‐related magmatism and accretionary orogenesis. Model 232Th/204Pb and 238U/204Pb broadly correlate with mapped crustal domains. More homogeneous and less radiogenic 238U/204Pb and 232Th/238U after 2.7 Ga suggests a shift to more juvenile sources, loss of early isotopic reservoirs and greater crustal reworking. U and Th are fractionated from Pb in Proterozoic orogens with abundant ferroan and anorthosite–mangerite–charnockite–granite(AMCG)‐suite magmatism. This fractionation suggests the removal of Pb‐rich lower crust, supporting petrogenetic models involving lithospheric foundering and magmatic underplating. Lithospheric thinning and associated magmatism may have contributed to high middle Proterozoic geothermal gradients. [ABSTRACT FROM AUTHOR]

A series of paired samples were analyzed to determine if high‐precision lead isotopic fingerprinting could help identify the source of lead in plumbing materials and drinking water. Samples were obtained of plumbing materials (lead service lines, copper pipe with lead solder, galvanized materials, and brass fixtures) from water utilities across the United States. Lead samples were taken from the material itself, from scales, and in some cases from associated water. The lead samples were analyzed to determine the ratios of the four stable lead isotopes present. The results enabled the identification of relationships between various components and further aided in the identification of the source of lead found in water and in pipe scales. Isotopic fingerprinting, as demonstrated in this study, could be used to determine if a galvanized line is a galvanized line requiring replacement (GRR) under the Lead and Copper Rule Improvements (USEPA, 2023). [ABSTRACT FROM AUTHOR]

The British Archaeological Association is a registered company and charity that promotes the study of archaeology and preservation of antiquities. They organize lectures, conferences, and study days, publish a journal, and have a governing body. In 2023, they held council meetings and an online AGM, and had a membership of 780 individuals. They organized a conference in Chichester, expressed gratitude to contributors, and participated in the Leeds International Medieval Congress. They also published the Journal of the British Archaeological Association, awarded scholarships, and reported their financial information. As of December 31, 2023, their net movement of funds was £33,561, resulting in a fund balance of £611,904. Their balance sheet shows fixed assets valued at £518,193 and current assets of £109,205. Their charitable expenditure for the year was £104,024, and their investments were valued at £518,193, with various funds and unit trusts listed. Two previous funds were merged into one ESG Income and Growth Fund. [Extracted from the article]

Understanding the critical thresholds of dissolved oxygen (O2) that trigger adaptive physiological responses in aquatic organisms is long hampered by a lack of robust, non-lethal or non-invasive methodologies. The isotope fractionation of triple O2 isotopes (18O/17O/16O) during respiration is linked to the amount of oxygen utilised, offering a potential avenue for new insights. Our experimental research involved measuring the oxygen isotope fractionation of dissolved O2 in closed-system aquatic respirometry experiments with wild sticklebacks (Gasterosteus aculeatus). These fish were either naturally adapted or experimentally acclimated to hypoxic and normoxic conditions. The aim was to observe their oxygen usage and isotope fractionation in response to increasingly severe hypoxia. Initial observations revealed a progressive 18O enrichment from the preferential uptake of 16O to a dissolved oxygen threshold of 3–5 mg O2 L–1, followed by an apparent reversal in oxygen isotope fractionation, which is mixing of 16O and 17O with the remaining O2 pool across all populations and indicative of a systematic change in oxygen metabolism among the fish. Unexpectedly, sticklebacks adapted to hypoxia but acclimated to normoxia exhibited stronger oxygen isotope fractionation compared to those adapted to normoxia and acclimated to hypoxia, contradicting the hypothesis that hypoxia adaptation would lead to reduced isotope discrimination due to more efficient oxygen uptake. These preliminary experimental results highlight the novel potential of using dissolved O2 isotopes as a non-invasive, non-lethal method to quantitatively assess metabolic thresholds in aquatic organisms. This approach could significantly improve our understanding of the critical oxygen responses and adaptation mechanisms in fish and other aquatic organisms across different oxygen environments, marking a significant step forward in aquatic ecological and physiological research. [ABSTRACT FROM AUTHOR]

Thick coal seams recorded abundant petrological, geochemical, and mineralogical information regarding their formation, which in turn can reflect the characteristics of the coal-forming environments, provenance attributes, paleoclimate, and so on. In order to explore the geochemical and lead isotope characteristics of thick coal seams, the No. 7 coal seam in the Datun mining area, Jiangsu Province of China, was selected as the research object. In this work, 29 samples (including coal, roof, and floor rock samples) were collected from three coal mines in the Datun mining area. Through an analysis of the mineral composition and element geochemical characteristics in the coal samples, the enrichment degree of trace elements and modes of rare earth elements were determined. The genetic mechanism of abnormal enrichment of enriched elements is discussed, especially the modes of occurrence and isotope characteristics of Pb. The results showed the following: (1) The main minerals in the coal samples include quartz, potassium feldspar, plagioclase, calcite, dolomite, pyrite, gypsum, and clay minerals, with clay minerals, calcite, quartz, and dolomite being the most common. (2) The major element oxides in coal mainly include SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O, TiO2, P2O5, and FeO. In the vertical direction, the variation of SiO2, Al2O3, Fe2O3, MgO, K2O, and FeO in coal samples from the three coal mines is consistent. The average value of Al2O3/TiO2 in the samples of Kongzhuang, Longdong, and Yaoqiao coal mines is 28.09–50.52, which basically locates the samples in the felsic source area, such that the sediment source is considered to be felsic source rock. (3) Elements U, La, Pb, and other elements are more enriched in Kongzhuang coal mine samples; elements Th, U, La, Pb, and other elements are more enriched in the Longdong coal mine samples; and elements Th, U, La, Pb, and other elements are more enriched in the Yaoqiao coal mine samples. Furthermore, W is enriched in Yaoqiao mine samples and is highly enriched in Longdong mine samples. The mining area is generally rich in the elements U, La, and Pb. The distribution curves of rare earth elements in the three mines are inclined to the right, with negative Eu anomalies. The enrichment is of the light rare earth enrichment type. (4) Pb isotope data show that the samples from the three mines are mainly distributed in the orogenic belt and the subduction zone lead source areas, where the upper crust and the mantle are mixed, with individual sample points distributed in the mantle and upper crust lead source areas. [ABSTRACT FROM AUTHOR]

Chemical 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. [ABSTRACT FROM AUTHOR]

The northern margin of the North China Craton is one of the most important porphyry-skarn molybdenum ore belts in the world. The eastern Hebei Province, which contains a high number of molybdenum and gold (molybdenum) resources, is an important portion of the northern margin of the North China Craton. Xichanggou and Huashi, located in eastern Hebei, are quartz-molybdenum vein deposits that are intimately associated with intrusions that are deeply concealed in the mining area. This work presents two zircon U-Pb dates and ten molybdenite Re-Os ages from samples of the aforementioned two deposits in order to determine the timing of the intrusion and mineralization. The zircon U-Pb ages of the quartz monzonite porphyry from Xichanggou are determined to be 163.3 ± 0.3 Ma and 162.8 ± 0.4 Ma. The molybdenite Re-Os dating yielded ages of 160.3 ± 4.6 Ma for Xichanggou and 171.4 ± 19 Ma for Huashi, respectively. The isotopic composition of oxygen and hydrogen of the ore-forming fluid from Huashi, as indicated by the δDV-SMOW values (−80.0‰ to −67.6‰) and δ18OH2O values (−1.86‰ to 2.33‰), suggests that the fluid is primarily composed of water derived from magma, with some contribution from atmospheric precipitation. The sulfur isotope values (δ34S) of sulfides from Xichanggou range from 6.5‰ to 7.1‰, while the δ34S values from Huashi range from 3.3‰ to 4.9‰. The lead isotope ratios (206Pb/204Pb and 207Pb/204Pb) of sulfides from Xichanggou and Huashi average at 17.414, 15.428, and 17.591, 15.379, respectively. The Re-Os isotopic compositions of ore sulfides mostly fall within the range of 318 ppm to 50,114 ppm. These isotopic compositions indicate that the materials responsible for the formation of the ores in Xichanggou and Huashi primarily originate from the melting of lower crust materials that have been contaminated by the mantle. Based on the regional data, the molybdenum deposits in eastern Hebei were formed in multiple periods, specifically approximately 170 Ma and 160 Ma in Huahsi and Xichanggou, respectively. The subduction of the Paleo-Pacific plate during the middle–late Jurassic period led to the partial remelting of lower crust material, resulting in the acquisition of a significant quantity of metal elements (Mo), which were subsequently deposited. [ABSTRACT FROM AUTHOR]

We investigate the use of single particle inductively coupled plasma time-of-flight mass spectrometry (spICP-TOFMS) to measure isotopic ratios within individual sub-micron particles and explore the advantages and limitations of this method. Through the analysis of samarium (Sm) isotopes—147Sm and 149Sm—in individual monazite particles, and lead (Pb) isotopes—206Pb and 208Pb—in individual galena particles, we demonstrate that isotope ratios recorded by spICP-TOFMS have precision controlled by Poisson statistics. This precision depends on the signal amount measured per isotope from an individual particle: as particle size increases, more counts of each isotope are detected, and the precision improves. In monazite particles with mass amounts of Sm from 0.04 to 4 fg, recorded isotope-ratio precision (relative standard deviation, RSD) ranged from 43% to 5%. However, the average isotope ratio from a particle population is still accurate; the molar ratio determined for 149Sm/147Sm was 0.912, which is within 1% of the expected ratio. Lead isotopic composition varies widely in nature because 206Pb, 207Pb, and 208Pb are radiogenic isotopes that decay from thorium (Th) and uranium (U). In the analysis of lead isotopes from galena particles, we found that the RSD for 208Pb/206Pb ratio ranged from 32% to 2% for particles with 1.4 to 80 fg of Pb. We further explore the use of spICP-TOFMS for radiometric dating of monazite particles. Monazite is used in geochronology for radiometric dating based on 208Pb/232Th and 206Pb/238U ratios. spICP-TOFMS analyses of individual monazite particles that contain only 0.02–80 fg of Th and 0.03–30 fg of U showed radiogenic Pb-isotope signatures and a median age of 550 Ma. We also show that the spread of ages from monazite particles is broader than explainable by Poisson statistics, revealing real variation in age or depletion/enrichment of Pb, Th, and/or U in the particles. Overall, we demonstrate that spICP-TOFMS can be used for accurate isotope-ratio analysis with precisions down to a few percent; however, understanding measurement noise is critical to define the significance of isotope ratios measured from individual particles. [ABSTRACT FROM AUTHOR]

This article presents the results of lead isotope analysis (LI) conducted on four bronze anklets from an early Iron Age burial (Burial D/F3) at the site of Ḥorvat Tevet, Israel. The results show that the copper in these items most likely originated in Timna. All the known LI data from the Late Bronze and early Iron Age southern Levant is then plotted to demonstrate that Arabah copper dominated the region in the early Iron Age. The significance of these objects for reconstructing exchange networks in the early Iron Age Jezreel Valley is briefly explored. We then turn to discussing the social meaning of these objects. Based on a catalogue of all known southern Levantine burials dated between the Late Bronze III (12th century bce) and Iron IIA (9th century bce) containing anklets or bracelets in association with skeletal remains with biological sex and age determinations, we conclude this was likely the burial of a high-status female. [ABSTRACT FROM AUTHOR]

Seniority is the number of nucleons not in pairs coupled to zero angular momentum. Conditions for the conservation of seniority are well known and are shown here to be related to particle–hole conjugation. The symmetry of seniority gives rise to selection rules in the γ decay of nuclei, which may lead to the formation of isomers. Examples of seniority isomers are discussed in the nickel and lead isotopes, and in the N = 50 , 82 and 126 isotones. It is shown that a strong attractive quadrupole matrix element of the nucleon–nucleon interaction disfavours the existence of seniority isomers. [ABSTRACT FROM AUTHOR]

It is shown that from the point of view of the generalized pairing Hamiltonian, the atomic nucleus is a system with small entanglement and can thus be described efficiently using a 1D tensor network (matrix‐product state) despite the presence of long‐range interactions. The ground state can be obtained using the density‐matrix renormalization group (DMRG) algorithm, which is accurate up to machine precision even for large nuclei, is numerically as cheap as the widely used Bardeen‐Cooper‐Schrieffer (BCS) approach, and does not suffer from any mean‐field artifacts. This framework is applied to compute the even‐odd mass differences of all known lead isotopes from 178Pb$^{178}\text{Pb}$ to 220Pb$^{220}\text{Pb}$ in a very large configuration space of 13 shells between the neutron magic numbers 82 and 184 (i.e., two major shells) and find good agreement with the experiment. Pairing with non‐zero angular momentum is also considered and the lowest excited states in the full configuration space of one major shell is determined, which is demonstrated for the N=126$N=126$, Z≥82$Z\ge 82$ isotones. To demonstrate the capabilities of the method beyond low‐lying excitations, the first 100 excited states of 208Pb$^{208}\text{Pb}$ with singlet pairing and the two‐neutron removal spectral function of 210Pb$^{210}\text{Pb}$ are calculated, which relate to a two‐neutron pickup experiment. [ABSTRACT FROM AUTHOR]

Abstract In Earth and planetary science, Pb isotopic composition is well known to play a key role in deciphering the origin and evolution of materials because they provide unique chronological and/or indigenous regional information as a radiogenic daughter nuclide from U and Th. To determine such an isotopic composition, mass spectrometers have been widely used over several decades, which requires a destructive/consuming treatment such as sputtering, laser ablation and thermal ionization. Here, we first report the non-destructive Pb isotopic measurement of natural galena (PbS) using the energy shift of muon-induced characteristic X-rays. The observed Pb isotopic composition of the natural galena is in good agreement with that obtained by conventional mass spectrometry. Such a muon-based Pb isotopic analysis method is expected to be applied to identify the production area of archaeological artefacts (e.g. bronze products), where non-destructive analysis is highly desirable compared to conventional mass spectrometry.

In Earth and planetary science, Pb isotopic composition is well known to play a key role in deciphering the origin and evolution of materials because they provide unique chronological and/or indigenous regional information as a radiogenic daughter nuclide from U and Th. To determine such an isotopic composition, mass spectrometers have been widely used over several decades, which requires a destructive/consuming treatment such as sputtering, laser ablation and thermal ionization. Here, we first report the non-destructive Pb isotopic measurement of natural galena (PbS) using the energy shift of muon-induced characteristic X-rays. The observed Pb isotopic composition of the natural galena is in good agreement with that obtained by conventional mass spectrometry. Such a muon-based Pb isotopic analysis method is expected to be applied to identify the production area of archaeological artefacts (e.g. bronze products), where non-destructive analysis is highly desirable compared to conventional mass spectrometry. [ABSTRACT FROM AUTHOR]

A collection of bronze chariot-horses was discovered in the Yang'an Han tomb in Qionglai City, Sichuan Province. These bronzes was used as burial objects, symbolizing the high status of the tomb owner during his lifetime. To analyze the samples taken from the bronze chariot-horses, various scientific techniques were employed, including metallographic microscopy, scanning electron microscope energy dispersive (SEM–EDS), multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), and inductively coupled plasma-atomic emission spectrometer (ICP-AES) were used to analyze samples from the bronze chariot-horses. Unlike most Han bronzes made of leaded tin-bronze, the bronze chariot-horses were crafted using copper and tin, and their metallographic structure revealed that they were cast. The origin of the copper material used for the bronze chariot-horses differed noticeably from that of bronzes excavated in the Sichuan area from the late Warring States period and Western Han period. Historical documents and archaeological findings suggested that the owners of the bronze chariot-horses were possibly vassals. As the Sichuan region was governed by the central government of the Western Han Dynasty through the establishment of prefectures and counties rather than through the enfeoffment system, the presence of the bronze chariot-horses in Yang'an Han tomb may be related to the family of Liu Yue (刘越). The analysis of the lead isotope data indicated that the copper material likely originated from the southeastern Hebei and western Shandong, providing strong evidence for the link between the bronze chariot-horses and the family of Liu yue in terms of resource circulation. [ABSTRACT FROM AUTHOR]

This 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. [ABSTRACT FROM AUTHOR]

Surprising 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. [ABSTRACT FROM AUTHOR]

This 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. [ABSTRACT FROM AUTHOR]

Purpose: The lead-203 (203Pb)/lead-212 (212Pb) elementally identical radionuclide pair has gained significant interest in the field of image-guided targeted alpha-particle therapy for cancer. Emerging evidence suggests that 212Pb-labeled peptide-based radiopharmaceuticals targeting somatostatin receptor subtype 2 (SSTR2) may provide improved effectiveness compared to beta-particle-based therapies for neuroendocrine tumors (NETs). This study aims to improve the performance of SSTR2-targeted radionuclide imaging and therapy through structural modifications to Tyr3-octreotide (TOC)-based radiopharmaceuticals. Methods: New SSTR2-targeted peptides were designed and synthesized with the goal of optimizing the incorporation of Pb isotopes through the use of a modified cyclization technique; the introduction of a Pb-specific chelator (PSC); and the insertion of polyethylene glycol (PEG) linkers. The binding affinity of the peptides and the cellular uptake of 203Pb-labeled peptides were evaluated using pancreatic AR42J (SSTR2+) tumor cells and the biodistribution and imaging of the 203Pb-labeled peptides were assessed in an AR42J tumor xenograft mouse model. A lead peptide was identified (i.e., PSC-PEG2-TOC), which was then further evaluated for efficacy in 212Pb therapy studies. Results: The lead radiopeptide drug conjugate (RPDC) — [203Pb]Pb-PSC-PEG2-TOC — significantly improved the tumor-targeting properties, including receptor binding and tumor accumulation and retention as compared to [203Pb]Pb-DOTA0-Tyr3-octreotide (DOTATOC). Additionally, the modified RPDC exhibited faster renal clearance than the DOTATOC counterpart. These advantageous characteristics of [212Pb]Pb-PSC-PEG2-TOC resulted in a dose-dependent therapeutic effect with minimal signs of toxicity in the AR42J xenograft model. Fractionated administrations of 3.7 MBq [212Pb]Pb-PSC-PEG2-TOC over three doses further improved anti-tumor effectiveness, resulting in 80% survival (70% complete response) over 120 days in the mouse model. Conclusion: Structural modifications to chelator and linker compositions improved tumor targeting and pharmacokinetics (PK) of 203/212Pb peptide-based radiopharmaceuticals for NET theranostics. These findings suggest that PSC-PEG2-TOC is a promising candidate for Pb-based targeted radionuclide therapy for NETs and other types of cancers that express SSTR2. [ABSTRACT FROM AUTHOR]

The kink in the nuclear charge radii of lead isotopes is studied in the relativistic mean field approximation framework, using the parameter set NL3 ∗ . Within this approach, it is shown that the small component of the single-particle Dirac spinors plays an essential role in the kink formation through its effects on the single-particle central potential. This is because the structure of this potential in terms of the σ -scalar and ω -vector fields and the contributions of the small component to the scalar and nucleon densities have opposite signs. The impact of the spin-orbit interaction of the valence neutrons on the kink, through its effects on their wave functions, is very small for 1i states but significant for 2g states. Due to relativistic contributions, the effects on the kink of neutrons in the valence levels of a spin-orbit doublet with j = l + 1 / 2 and j = l - 1 / 2 are rather different from each other, even in the limit case of neglecting their spin-orbit interaction. [ABSTRACT FROM AUTHOR]

Lead isotope values for volcanogenic massive sulfide (VMS) deposits provide important insights into metal sources and the nature of pre-accretionary tectonostratigraphic terranes and underlying basements. Deposits of this type in New England formed in diverse tectonic settings including volcanic arcs and backarcs, a supra–subduction zone arc, a rifted forearc foreland basin, and a rifted continental margin. Following VMS mineralization on or near the seafloor, components of the tectonostratigraphic assemblages—volcanic ± sedimentary rocks, coeval intrusions, sulfide deposits, and underlying basements—were diachronously accreted to the Laurentian margin during the Paleozoic. Lead isotope data for galena show relatively large ranges for 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb. Evaluation of potential lead sources, using for comparison Pb-isotope data from modern and ancient settings, suggests that principal sources include the mantle, volcanic ± sedimentary rocks, and deeper basement rocks. Integration of the Pb-isotope values with published data such as Nd isotopes for the volcanic rocks and from deep seismic reflection profiles points to the involvement of several basements, including those of Grenvillian, Ganderian, Avalonian, and West African (and (or) Amazonian) affinity. Clustering of Pb-isotope data for VMS deposits within individual Cambrian and Ordovician volcanic and volcanosedimentary settings, delineated by differences in 206Pb/204Pb and µ (238U/204Pb) values, are consistent with lead derivation from at least four and possibly five different tectonostratigraphic assemblages with isotopically distinct basements. Collectively, our Pb-isotope data for New England VMS deposits provide a novel window into the nature of subarc basement rocks during pre-accretionary sulfide mineralization outboard of Laurentia during early Paleozoic time. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive archaeometallurgical analysis of 21 bronze rings recovered from the Nanhai No. I shipwreck, a remarkable historical site dating back to the Southern Song Dynasty (1127–1279 AD). The shipwreck, located in the South China Sea, has provided a unique window into the trade and contraband activities of the time. Through a meticulous examination of their composition, microstructure, trace elements, and lead isotopes by SEM, metallography, MC-ICP-MS, and ICP-AES, we unveil the manufacturing techniques, material origins, and the latent details within these seemingly ordinary artifacts. These bronze rings share high-lead content with other Song Dynasty bronzes. They are classified into three groups based on their copper and lead composition, with one group aligning with historical records, hinting at pre-prepared complex alloys designed for specific purposes. The stability of trace elements and lead isotopes in the rings indicates Guangdong region as the most probable source of the raw materials. These findings lead to the speculation that Nanhai No. I may have docked at a Guangdong port to replenish its cargo, including contraband goods such as bronze rings, before departing the Song Dynasty's territory with minimal scrutiny. In summary, this research enhances our understanding of ancient trade and smuggling practices and showcases archaeometallurgy's potential in unveiling the untold stories behind historical artifacts. [ABSTRACT FROM AUTHOR]

Abstract This study identifies the lead ores used to produce lead artifacts used by the Romans between the first and eighth centuries AD during the construction of the fort and then the town of Novae (N. Bulgaria). For this purpose, lead samples were taken from pipes, joints of columns and pedestals, and from a lead ingot. The samples were analyzed for lead isotopes and the results were compared to literature data for Roman mines from what is now Bulgaria, Greece, North Macedonia, Montenegro, Bosnia and Herzegovina, Italy, Germany, and Romania. Pb isotope results indicate that during the earlier stages of Novae's establishment, lead was most likely supplied from several different mines located in the Balkan area. Several samples also show Pb isotopes indicating mixing of lead from mines in the Balkan area. Then in the fourth—fifth century AD lead began to be supplied mainly from mines located in NW Bulgaria, with one sample possibly from deposits in German. This is evidenced by the matching of the results obtained for the ores to the data for deposits from these regions. Two possibly recycled samples were also identified. Deposits from other European regions did not match samples from Novae, indicating that majority of the lead was sourced from mines in the Balkan region.

This archive lists ~8000 Bronze Age British axeheads, alongside associated compositional analyses, isotopic measurements and radiocarbon dates. It integrates several major existing data collection efforts and published catalogues, whilst also providing a self-consistent basic typology. It is archived as four related flat-sheet text files and could be reused to support quantitative assessment of geographic and temporal patterns in metalwork style, deposition, recovery, hoard co-occurrence and/or metallurgical compositions to name just a few salient topics.

The diffuse presence of small copper ore deposits in the Alpine area, mostly exploited since Late Medieval times, led most scholars to assume that these deposits may actually be active much earlier and that many of the circulating prehistoric metal objects found in the area were produced with local copper sources. This assumption was recently validated for the Recent Bronze Age through the use of lead isotope tracers, and well supported by the archaeometallurgical evidences found in the South-Eastern Alps. However, the scarcity of available lead isotope data for pre-Bronze Age metals precluded to date the reconstruction of the metal flow through the Late Neolithic and Eneolithic (or Copper Age). Based on 49 new analyses of important archaeological objects from the Alpine region, the Po River Valley and Central Italy, mostly axes dated from the Late Neolithic to the Late Eneolithic, here we show that the diffusion of copper in Northern Italy (approximately 4500–2200 BC) includes three major periods of metal use and/or production, each related to specific ore sources. The South Alpine copper was massively used only starting from the middle of the 3rd millennium BC, in connection or slightly earlier than the Beaker event. [ABSTRACT FROM AUTHOR]

This study identifies the lead ores used to produce lead artifacts used by the Romans between the first and eighth centuries AD during the construction of the fort and then the town of Novae (N. Bulgaria). For this purpose, lead samples were taken from pipes, joints of columns and pedestals, and from a lead ingot. The samples were analyzed for lead isotopes and the results were compared to literature data for Roman mines from what is now Bulgaria, Greece, North Macedonia, Montenegro, Bosnia and Herzegovina, Italy, Germany, and Romania. Pb isotope results indicate that during the earlier stages of Novae's establishment, lead was most likely supplied from several different mines located in the Balkan area. Several samples also show Pb isotopes indicating mixing of lead from mines in the Balkan area. Then in the fourth—fifth century AD lead began to be supplied mainly from mines located in NW Bulgaria, with one sample possibly from deposits in German. This is evidenced by the matching of the results obtained for the ores to the data for deposits from these regions. Two possibly recycled samples were also identified. Deposits from other European regions did not match samples from Novae, indicating that majority of the lead was sourced from mines in the Balkan region. [ABSTRACT FROM AUTHOR]

The paper considers Sr, Nd, and Pb isotope data obtained for two cores of bottom sediments taken in the Oga and Tsivolki bays of Severny Island of the Novaya Zemlya archipelago. The studied sequence of sediments from Oga Bay has accumulated over the last thousand years. The 87Sr/86Sr ratio decreases from top to bottom down the section from 0.72225 to 0.71995, the value of εNd varies from –6.1 to –5.5. The Pb isotopic composition varies within narrow limits: the 206Pb/204Pb ratio from 19.107 to 19.139, the 207Pb/204Pb ratio from 15.632 to 15.635, and the 208Pb/204Pb ratio from 38.568 to 38.635. A rapid decrease in the 87Sr/86Sr ratio at a relatively stable neodymium and lead isotope composition indicates a change in the source of the clastic material. This can be explained by the fact that the material of the destruction of Permian clay shales, and then Devonian–Silurian sedimentary carbonates, first entered the area of glacier abrasion and further, respectively, into the sedimentation zone. The sediment column from Tsivolki Bay was formed over a little more than 10 000 years. Based on the Sr, Nd, and Pb isotope ratios, these bottom sediments are divided into lower and upper parts: before and after 150 cm (or ~3500 years). In the lower part of the column, the 87Sr/86Sr ratio increases from 0.72055 to 0.72580, the value of εNd remains approximately the same and varies around –8.2. In the upper part, the 87Sr/86Sr ratio drops to 0.72049 in the near-surface layer; at the same time, the value of εNd increases to –6.4. At the boundary of these two units, the 206Pb/204Pb ratio abruptly changes from about 18.0 in the lower part to 19.3 in the upper part and 208Pb/204Pb from about 36.5 in the lower part to 38.7 in the upper part of the section. The change in the Sr, Nd, and Pb isotope characteristics is likely a reflection of changes in the composition of the rocks in the area where the basin was removed, which is now being eroded by the glacier. Comparison with modern sources supplying clastic material to the Kara Sea showed that the material is supplied to the Oga and Tsivolki bays only from Novaya Zemlya. [ABSTRACT FROM AUTHOR]

This study combines various methods to investigate bronze artifacts excavated at the Thengkham East site in Vilabouly, Laos, in 2018. These excavated copper objects are consistent with other previously published copper objects from Vilabouly in terms of style, alloying ratios, and forming techniques, demonstrating that similar metallurgical traditions were indeed employed within Vilabouly. For dagger-axes with very low tin content, based on cultural connections between Southeast Asia and Yunnan, China, this study proposes the hypothesis that the dagger-axes unearthed in Vilabouly are funerary implements. The study of lead isotope ratios indicates evidence for the exchange of a multi-layered artifact between the mining/ore processing site and general consumption site at Vilabouly. This may indicate that the trading network within Vilabouly is based on intermediate products. Introducing new lead isotope ratio data for copper objects from Thailand and Cambodia, the comparative studies reinforced the widespread view that during the early Iron Age in Ban Non Wat, central Laos succeeded Thailand in supplying copper to various regions of Southeast Asia. [ABSTRACT FROM AUTHOR]

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Isotopic fractionation of evaporating waters has been studied constantly in recent decades, particularly because it enables calculation of both the volume of water evaporated from a water body and the isotopic composition of its source water. We studied the stable water isotopic composition of an artificial pan filled with water and subject to total evaporation in a sub-humid environment, in order to put into practice an operational method for estimating the time since disconnection of riverine pools when these are sampled for the quality of aquatic life. Results indicate that (i) when about 70 % of pan water had evaporated and its isotopic composition had become enriched in heavy isotopes, some subsequent periods of depletion instead of enrichment happened; and (ii) the customary application of isotopic fractionation equations to determine the isotopic composition of the water in the pan using weekly averaged atmospheric conditions (temperature and relative humidity) strongly underestimated the changes observed but predicted an early depletion of heavy isotopes. The first result, rarely reported in the literature, was found to be fully consistent with the early studies of the isotopic composition of evaporating waters. The second one could be attributed to the fact that weekly averages of temperature and relative humidity strongly overestimated air relative humidity during daylight periods of active evaporation. However, when the fractionation equations were parameterized using temperature and relative humidity weighted by potential evapotranspiration at sub-hourly time steps, they adequately reproduced the observed isotopic composition of the water in the pan, including the late periods of heavy isotope depletion. We demonstrate how weekly increases in air relative humidity when the pan water was already enriched in heavy isotopes led to their depletion. We also analyse the errors that can be incurred if time averages are used instead of flux-weighted meteorological data for model parameterization and if unidentified periods of heavy isotope depletion occur. Our results should be taken into account when applying fractionation equations, particularly in conditions or areas with high air relative humidity. [ABSTRACT FROM AUTHOR]

We show, from a 16.6 ka record of lead isotopes from a core sediments in Dahu Swamp in eastern Nanling Mountains, that the chemical weathering responds to changes in climatic conditions. Pb isotopic signals reveal that the local weathered granitoid was the dominant source of Pb deposition. However, two isotopic excursions appeared from 15.5–15.2 and 5.2–4.8 ka BP, which coincide with the dry/cold H1 event and the mid- and late-Holocene respectively, likely suggesting an additional contribution of aeolian dust from North China. Even more, more radiogenic Pb signal of E2 exhibits a mixed contribution of enhanced anthropogenic mining. We expect strong enough EAWM would dominate these two intervals. Supported by multi-proxy records, we conclude that variations Pb isotopic signals (e.g., 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios) are closely related to climate-induced chemical weathering. Synchronous variations of 208Pb/204Pb, 206Pb/204Pb and 207Pb/204Pb ratios in the core display a congruent Pb isotope signals released from both U- and Th-rich accessory minerals. During intensive chemical weathering under wetter/warmer conditions (e.g., the Bølling and Allerød events, and the Holocene Optimum period), more preferential release of radiogenic 206Pb, 207Pb and 208Pb can be absorbed by fine detritus and then eroded to the lake thus resulting in increased 208Pb/204Pb, 206Pb/204Pb and 207Pb/204 ratios in sediments, and vice versa if a drier/colder climate dominates (e.g., the H1, the Older and Younger Dryas events, and the mid- & late-Holocene). The inferred changes in chemical weathering from Dahu sediments have varied in tandem with multi-regional monsoonal proxies in China, and exhibited a sensitive response of chemical weathering to global climate change. [ABSTRACT FROM AUTHOR]

The periodically detached and regenerated antlers are a diagnostic trait of deer (family Cervidae) and represent the most rapidly growing bones of mammals. During their species-specific and seasonally fixed growth period of a few months, antlers can accumulate large amounts of 'bone-seeking' elements that are incorporated into the bone mineral. This makes antlers 'naturally standardised' environmental samples that can be used to monitor environmental pollution of deer habitats by these elements. The present contribution reviews studies utilising hard antlers as environmental archives to reconstruct temporal and spatial variation of contaminant levels in different geographic regions. We further discuss the use of lead isotope signatures in antlers for source apportionment of environmental lead and the impact of excess fluoride uptake on antler mineralisation. In addition, promising areas for future research using antlers as bioindicators are discussed. Antlers are a unique trait of deer and can be used as 'naturally standardised' environmental samples for monitoring ambient levels of bone-seeking pollutants. The present paper reviews basic aspects of antler growth and the history of using antlers as monitoring units in environmental research. Furthermore, we identify promising approaches for future studies using antlers as bioindicators. [ABSTRACT FROM AUTHOR]

In the present study, 37 lead artefacts were characterised to identify possible lead sources allowing to establish trade fluxes concerning food and textile products during Roman times. These artefacts were uncovered by dredging works at the Arade River estuary (Portimão). The city of Portimão (Lusitania province) was an important harbour, where several fish-processing factories were installed, and Arade River provides major access to the hinterland, both displaying an important commercial activity during the Late Antiquity. The methodology includes the typological and chemical (elemental and Pb isotopes) characterisation of artefacts. Samples were divided into the following: (i) rectangular plaques with decorations in relief such as tridents, fishes, or palms leaf, an iconography known to be displayed in some African amphora handles; (ii) small plaques with one perforation and incised Roman numerals, probably related with textile products; and (iii) fishing net weights, smooth plaques of unknown functionality, and a small rectangular prismatic plaque, perhaps an ingot. Elemental analysis was performed by ICP-MS, and results were interpreted by multivariate statistical analysis, which suggested different processes to obtain raw materials, namely lead obtained by the reduction of litharge or smelting of silver-poor galena. Cluster analysis grouped most of samples with motif depictions, which were further analysed by MC-ICP-MS to determine Pb isotope ratios. The possible sources of lead were identified by combining archaeological data with the nearest Euclidean neighbours using a large database comprising the Iberian Peninsula and Mediterranean region. The Pb isotope signatures suggested lead sources located not only in the Iberian Peninsula but also in North Africa, evidencing a long-distance trade between those Roman provinces. [ABSTRACT FROM AUTHOR]

This study evaluates the feasibility of using the internal standard (IS) method and optimized regression model (ORM) to determine lead isotope ratios without separating Pb from many different types of matrices. The effect of typical interferents at increasing concentrations was investigated using model samples. We have demonstrated that Pb isotope ratio measurements without matrix separation give equally accurate and precise results as those obtained with matrix separation. Finally we used a new protocol to measure the isotope ratio of Pb in environmental, geological and archaeological samples with very limited availability (3 mg) and low lead content (30 mg kg−1). Such samples have so far been problematic for MC-ICP-MS isotopic analysis due to the difficulties with separating such small amounts of lead using ion exchange resins. Lead isotope ratios were measured without separation of lead from the sample using two protocols. In the first, the internal standard method was used as a means of calibration. In the second, the optimized regression model was used. In this case there were no statistically significant differences between the protocols compared. Both approaches gave statistically similar results. The protocol using IS is recommended as it is significantly simpler and less laborious and consumes lower volumes of sample solution. The protocol we developed can be applied to a wide range of samples (following some recommendations). To demonstrate the usefulness of the new procedure, we applied it to different types of samples containing lead at different concentrations. In particular, we focused on historical samples because their availability is very limited and collecting a sufficiently large sample is always a major problem. Where possible, we compared our results with literature values. The new protocol, by eliminating the sample preparation step, allowed us to measure about four times more samples per day (about 12–15) compared to the classical method (with Pb separation using ion exchange resins). We also present, for the first time, a new method for the non-destructive sampling of manuscripts for isotopic analysis, involving the extraction of lead from the object into indicator papers soaked in 4,7-diphenyl-1,10-phenanthroline. [ABSTRACT FROM AUTHOR]

The Gongguan deposit in southern Qinling district, central China, is characterized by a Hg and Sb metal association, with proven reserves of 7,543 t Hg and 17,100 t Sb. The Hg-Sb mineralized veins are primarily hosted by local Lower Devonian dolomite. Three primary paragenetic stages have been identified, including (I) pyrite-dolomite-quartz, (II) stibnite-cinnabar-quartz-calcite and (III) post-ore calcite. Dominant mercury and antimony mineralization occurred in stage II. Fluid inclusion microthermometry of quartz and calcite reveal that the Hg-Sb mineralization is associated with a low temperature (142° to 240 °C) and low salinity (< 8.6 wt% NaCl equivalent) fluid, belonging to a H2O-NaCl ± CO2 system. The H–O isotope compositions (δDH2O = −84 to −63‰, δ18OH2O = 1.3 to 12.7‰) of the hydrothermal fluid suggest a mixture of metamorphic fluid and meteoric water. In situ sulfur isotope results of cinnabar (δ34S = 3.4 to 14.5‰), stibnite (δ34S = 4.9 to 10.5‰) and pyrite (δ34S = 3.8 to 5.4‰) indicate sulfur sources from decomposition of diagenetic pyrite and/or the thermochemical sulfate reduction in local sedimentary rocks. In situ obtained 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios (18.006 to 18.362, 15.445 to 15.610 and 37.871 to 38.288, respectively) of stibnite and pyrite substantially differ from those for the regional Carlin Au-Sb and SEDEX Pb–Zn ore deposits. The lead isotope results indicate that the underlying Paleozoic (Silurian to Cambrian) strata and Precambrian metamorphic basement supplied substantial metals for the studied Hg-Sb deposit, whereas the host Devonian carbonates did not contribute significant metals. In summary, we propose that fluid mixing between metamorphic fluid and meteoric water was the main cause for carbonate-hosted Hg-Sb deposition at Gongguan, which reduced the stibnite solubility, oxidized mercury (Hg0 to Hg2+), favoring the process of dedolomitization. [ABSTRACT FROM AUTHOR]

This article presents contextual evidence for the interpretation of lead isotope analysis (LIA) of artefacts from the Archaic Greek Mediterranean. In particular, I make a response to Wood's suggestion in Archaeometry (2022, first view, 'Other ways to examine the finances behind the birth of Classical Greece') that the end of the production of lead votive figurines in Sparta might have been caused by Athenian restrictions to Laurion lead exports, drawing on new LIA of the Spartan lead votives and wider considerations concerning the trade, cost and volume of lead in the 7th to 5th century bce Mediterranean. [ABSTRACT FROM AUTHOR]

A small and isolated hydrothermal vein-type Sb deposit is hosted by a lamprophyre dike which penetrated Neoproterozoic to early Cambrian volcanosedimentary successions near Chříč in the Teplá-Barrandian Unit, Czech Republic. Hydrothermal minerals were formed in several consecutive mineralization stages, separated by long pauses in hydrothermal fluid flow. Early Stage I is characterized by the formation of carbonates of dolomite-ankerite series (Carb I) and arsenopyrite with an imprecise Re-Os age of ~570 to 510 Ma. Stage I was followed by tectonic movements and brecciation. The second mineralization stage (Stage II) is characterized by the precipitation of quartz (Qtz I) and Sb minerals (predominantly stibnite) while the third stage (Stage III) is marked by the presence of carbonates of dolomite-ankerite series (Carb II) and quartz (Qtz II) along with Cu, Zn, Pb, Ag and Fe sulfides. Lead isotope data of galena indicate a Variscan age of Stages II-III. These stages were followed by precipitation of another generation of carbonate of dolomite-ankerite series (Carb III, Stage IV), quartz (Qtz III, Stage V) and formation of Sb supergene minerals. The earlier reported occurrence of gold was not confirmed in the studied rock samples but three types of gold particles of variable fineness, with one of them indicating a local origin, were found in the heavy mineral concentrate from a local creek. Elevated Au concentrations were found in arsenopyrite and pyrite. The ore-forming hydrothermal fluid of the mineralization stage III was of H2O-CO2 type with minor CH4 admixture, medium salinity, and temperatures in the range of 258-350 °C with an observed temperature decrease from Stage II to Stage V. Oxygen isotope data of Carb II correspond to high d18Ofluid values (~ +7.5 = VSMOW) with a decrease in the fluid d18O to later stages. An important part of the carbonate carbon was derived from decomposition of organic matter or its high-temperature reaction with hydrothermal fluid. Considering the wide variation in d34S values of sulfides and elevated Sb contents in the TBU black shales, we anticipate that the origin of the Chříč mineralization is closely associated with a metal and carbon-sulfur remobilization from the TBU volcanosedimentary successions in response to Cadomian and Variscan tectonothermal events. [ABSTRACT FROM AUTHOR]

Rates of global and regional sea‐level rise between ~1850 and 1950 were high compared to those in preceding centuries. The cause of this sea‐level acceleration remains uncertain, but it appears to be pronounced in a small set of relative sea‐level proxy records from the Southern Hemisphere. Here we generate three new proxy‐based relative sea‐level reconstructions for southeastern Australia to investigate spatial patterns and causes of historical sea‐level changes in the Tasman Sea. Palaeo sea‐level estimates were determined using salt‐marsh foraminifera as sea‐level indicators. Records are underpinned by chronologies based on accelerator mass spectrometry 14C, radiogenic lead (210Pb), stable lead isotopes and palynological analyses. Our reconstructions show that relative sea level rose by ~0.2–0.3 m over the last 200 years in southeastern Australia, and rates of sea‐level rise were especially high over the first half of the 20th century. Based on modelled estimates of the contributing components to sea‐level rise, we suggest that the episode of rapid sea‐level rise was driven by barystatic contributions, but sterodynamic contributions were dominant by the mid‐20th century. Significant spatial variability in relative sea level indicates that local to sub‐regional drivers of sea level are also prominent. Our reconstructions significantly enhance our understanding of the spatiotemporal pattern of early 20th century sea‐level rise in the region. [ABSTRACT FROM AUTHOR]

There is a consensus that volcanism along the East African Rift System (EARS) is related to plume activities. However, because of our limited knowledge of the local lithospheric mantle, the dynamics of the plume are poorly constrained by magma chemistry. The Turkana Basin is one of the best places to study plume‐related volcanism because the lithospheric mantle there is unusually thin. New Ar‐Ar geochronology and geochemical data on lavas from western Turkana show that Eocene volcanics have relatively low 206Pb/204Pb (<19.1) and high εNd (>3.78). Their relatively high Ba/Rb (35–78) ratios suggest contributions from the shallow lithospheric mantle. Oligo‐Miocene Turkana volcanics have HIMU‐ and EMI‐ type enriched mantle signatures with overall lower Ba/Rb ratios, which is consistent with partial melting of plume material. Pliocene and younger Turkana volcanics have low Ba/Rb and Sr‐Nd‐Pb isotope ratios that resemble those of Ethiopian volcanics with elevated 3He/4He ratios. This temporal variation can be reconciled with a layered plume model where an outer layer of ancient recycled oceanic crust and sediment overlies more primitive lower mantle material. Beneath Ethiopia, the outer layer of the plume is either missing or punctured by the delamination of the thicker overlying lithospheric mantle at ca. 30 Ma, an event that would have facilitated the rapid upwelling of the inner portion of the plume and triggered the Ethiopian flood volcanism. The outer layer of the plume may be thicker in the southern EARS, which could explain the occurrence of young HIMU‐ and EMI‐type volcanics with primordial noble gas signatures. Plain Language Summary: We studied lavas from the Turkana Basin, Kenya, to understand the nature of the mantle beneath the East African Rift System (EARS). We found that only the oldest Turkana lavas (>35 Ma) show contributions from the shallow lithospheric mantle while younger lavas show more contributions from a mantle plume. Oligocene‐Miocene lavas (32 Ma −12 Ma) from Turkana show signatures of ancient oceanic crust and sediments recycled deep into the mantle while Pliocene and younger Turkana volcanics (<5 Ma) show signatures of the lower mantle. We proposed a layered plume model to explain these observations: the initial arrival of the mantle plume under Turkana first caused partial melting of the enriched components in the shallow lithospheric mantle in the Eocene; further upwelling caused the outer layer of the plume to melt and form lavas with HIMU‐ and EMI‐type of geochemical signatures; the inner part of the plume that consists of lower mantle material was finally able to melt and generate Afar‐type magmatism in the Turkana Basin in the Pliocene. Variability in the thicknesses of the outer layer of the plume could explain the geographic differences in volcanism across the EARS. Key Points: HIMU and EMI Turkana volcanism occurred mostly in the Miocene while Pliocene Turkana volcanics resemble high 3He/4He Afar volcanicsTemporal variation of Turkana volcanism indicates a layered plume with an outer layer of ancient recycled oceanic crust and sedimentsLithospheric mantle delamination may have punctured the outer layer of the plume and triggered Ethiopian flood volcanism [ABSTRACT FROM AUTHOR]

Continental rifting is usually viewed in terms of two contrasting models of active and passive extension. The origin of the Baikal Rift, adjacent to the southern part of the Siberian Craton, has been described by both models in the past. It is expected that basaltic magmatism in an active model scenario should be primarily sourced from a mantle plume or plume-fed asthenosphere, whereas melting of the lithospheric mantle is expected to be a predominant source for magmatism in the passive model. In this paper, we focus on the Miocene volcanic rocks sampled along two 60-km-long profiles that cross the boundary between the Neoproterozoic Tuva-Mongolian massif and the Archean-Paleoproterozoic Siberian Craton. Most of the samples studied are trachybasalts. In terms of trace element concentrations normalised to primitive mantle, the lavas mimic oceanic island basalt-like patterns with troughs at Rb, Th–U, Pb, and Y, and peaks at Ba, Nb, Ta, K, and Sr. Moreover, similar trace element patterns to the studied samples are also observed for Miocene and Quaternary lavas located in the southwestern of the Baikal Rift, and adjacent regions of non-rifted Mongolia. According to the ratio of CaO to MgO, and TiO2/Al2O3 to SiO2, the compositions of the studied lavas coincide with experimental melts derived from mafic lithologies. Trace element data of samples suggest that garnet was a residual phase during partial melting. The Sr-Nd isotopic characteristics of the studied lavas are 87Sr/86Sr 0.70427–0.70469 and 143Nd/144Nd 0.51267–0.51284. They are identical to the coeval Miocene lavas of neighbouring volcanic fields, but they differ from the Quaternary lavas that extend to lower 87Sr/86Sr (0.7038–0.7044) with near identical 143Nd/144Nd. Isotopes of Hf for studied samples show values εHf = 6.0–7.7, except for the two samples taken within the boundary between two lithospheric blocks with εHf 4.6 and 4.8. The δ18O of olivine from lava samples is everywhere higher than that of the asthenospheric mantle and ranges from 5.5 to 6.4‰. Variations of δ18O versus Mg#, 87Sr/86Sr and εHf in the studied samples do not correlate, but do unequivocally rule out crustal assimilation. The isotopic variations are consistent with recycling of mafic crustal lithologies at mantle depths. Lavas from the Tuva-Mongolian massif and the Siberian Craton differ in lead isotopes by lower values of 206Pb/204Pb (< 17.785) and higher values of Δ8/4Pb (61–75) for on-cratonic samples and the reverse relationship for off-cratonic lava (> 17.785 and 55–61), respectively. The equation for Δ8/4Pb = [208Pb/204Pb-(1.209*(206Pb/204Pb) +15.627)] *100 is from Hart (Nature , 309 , 753–757, 1984). The correlation of lead isotopes with the mafic recycled component, the sharp change of lead isotopic values at the cratonic boundary and decoupling of lead isotope ratios from other isotopic ratios lead us to suggest that the values of 206Pb/204Pb and Δ8/4Pb are associated with an ancient accessory mineral phase such as sulphide confined within the lithospheric mantle. The predominant role of the lithospheric sources in the formation of the Miocene volcanic rocks indicate that the volcanism of the Baikal Rift was caused by a passive tectonic process, rather than active rifting. [ABSTRACT FROM AUTHOR]