Lead Isotope Analysis Research Articles

Metallum Messallini – A New Roman Lead Ingot from the Danube Provinces

A Roman lead ingot with the mould mark metallo Messallini provides highly interesting insight into the economic side of power politics pursued by the first Roman emperor Augustus. The proprietor of the mine, Messallinus, can be identified with Marcus Valerius Messalla Messallinus, consul in 3 BC and governor of Illyricum in AD 6. At the beginning of the Illyrian revolt in AD 6 he achieved important victories over the insurgent tribes. The mines were likely a gift from Augustus (who owned mines in that region) to Messallinus for his deeds. The shape of the panel and the inscription on the ingot as well as lead isotope analysis suggest an origin in the ore regions of Serbia and the Kosovo. According to the isotope comparison, the mines were located in the district of today’s Novo Brdo in eastern Kosovo (Figure 1).

Chemical and Lead Isotope characterisation of First World War shrapnel balls and bullets used on the Alpine Austrian–Italian Front

Chemical and lead isotope characterisation was carried out on shrapnel balls and bullets dating back to the First World War (WWI). These ammunitions were widely utilised in the Alpine Austrian–Italian front located in the Italian Alps. The investigation has been performed using inductively coupled plasma quadrupole mass spectrometry equipped with an octopole reaction system (ORS-ICP-QMS). The main goal of this work was to identify the elemental and lead isotope composition of raw materials and to discriminate between the military objects analysed. The results of multi-elemental analysis indicate that the shrapnel ball samples consisted of soft Pb or hard Pb with Sb depending on the use, the weapon type and the specific nation. The Italian shrapnel balls were made from hard Pb, as opposed to those of the Austrian–Hungarian samples. Through the investigation of lead isotope ratios, it has been possible to differentiate most of the Italian shrapnel balls from those of Austrian–Hungarian origin. Furthermore, some Italian shrapnel balls had a different lead isotope composition depending on their calibre. The elemental composition and lead isotopic signature of bullets show a clear discrimination between the external jacket and the core in relation to projectile type and nationality. The bullet cores consist of Pb–Sb alloy regardless of the region of origin. This work allowed us to investigate the potential applications of trace elements and lead isotope analyses to discriminate military artefacts of different origins.

A study of the glazing techniques and provenances of Tang sancai glazes using elemental and lead isotope analyses

This study discusses the elemental compositions and lead isotope ratios of Tang sancai glazes unearthed from the Huangpu kiln, Huangye kiln and two Tang sancai tomb sites. The various glazes feature distinct lead isotope ratios and trace element characteristics, which can be interpreted as evidence for the use of different lead ore deposits and siliceous raw materials in the glazes. This is a strong indication that lead isotopes combined with trace element analysis could be used as a viable approach for identifying the provenance of Tang sancai of unknown origin by linking them to kiln sites, This provenance technique could be significant in the interpretation of ancient ceramic trade and communication patterns. In this study, the provenance of several Tang sancai glazes of uncertain origin were determined using this method: some Tang sancai wares unearthed in Xi'an City were produced in the kiln near Luoyang City and then traded to Xi'an City, providing an idea of ancient Tang sancai ceramic trade routes.

Using Pb isotope ratios of particulate matter and epiphytic lichens from the Athabasca Oil Sands Region in Alberta, Canada to quantify local, regional, and global Pb source contributions

Ambient air particulate matter (PM) was collected at the Wood Buffalo Environmental Association Bertha Ganter Fort McKay monitoring station in the Athabasca Oil Sand Region (AOSR) in Alberta, Canada from February 2010 to July 2011 as part of an air quality source assessment study. Daily 24-hour duration fine (PM2.5) and coarse (PM10–2.5) PM was collected using a sequential dichotomous sampler. 100 pairs of PM2.5 and PM10–2.5 were selected for lead (Pb) concentration and isotope analysis. Pb isotope and concentration results from 250 epiphytic lichen samples collected as far as 160 km from surface mining operations in 2008, 2011, and 2014 were analyzed to examine longer term spatial variations in Pb source contributions. A key finding was recognition of thorogenic 208Pb from eastern Asia in the springtime in the PM2.5 in 2010 and 2011. 206Pb/207Pb and 208Pb/207Pb isotope ratios were used in a three-component mixing model to quantify local, regional, and global Pb sources in the PM and lichen data sets. 47 ± 3% of the Pb in the PM2.5 at AMS-1 was attributed to sources from eastern Asia. Combined results from PM10–2.5 and PM2.5 indicate PM2.5 Pb contributions from eastern Asia (34%) exceed local AOSR sources of PM2.5 Pb (20%), western Canada sources of PM2.5 Pb (19%), and PM10–2.5 Pb from fugitive dust including oil sands (14%), tailings (10%), and haul roads (3%). The lichen analysis indicates regional sources contribute 46% of the Pb, local sources 32%, and global sources 22% over the 2008–2014 timeframe. Local sources dominate atmospheric Pb deposition to lichens at near field sites (0–30 km from mining operations) whereas regional Pb sources are prevalent at distal sites (30–160 km). The Pb isotope methodology successfully quantified trans-Pacific transport of Pb to the AOSR superimposed over the aerosol footprint of the world's largest concentration of bitumen mining and upgrading facilities.

New insights into brass nails from the 19th-century Akko Tower Wreck (Israel): Metallurgical characterization

Abstract The Akko Tower Wreck is the remains of a 25-m-long merchant brig dated to the first half of the 19th century. During the underwater excavations, 105 brass nails were retrieved from the shipwreck. The nails were divided into two groups based on their microstructure: Type A nails were characterized by Widmanstatten plates, while Type B nails by a dendritic microstructure. In each group there were miscellaneous nails, distinguished by their different shapes. Ten miscellaneous nails were characterized by XRF, light microscopy, SEM-EDS analysis, microhardness measurements, anisotropy of magnetic susceptibility examination, and lead isotope analysis. The brass nails were post-cementation products manufactured by casting. The microstructure combined with the AMS analysis, indicated that Type A nails were of better quality than Type B ones. The lead isotope analysis of the nails suggested that their raw material most likely originated in Great Britain.

(Re)sources: Origins of metals in Late Period Egypt

Metal trade and access to raw materials during the Late Bronze Age—roughly covering the New Kingdom in Egypt—have received substantial attention from past and present scholarship. Despite copper and lead remaining essential commodities afterwards, our knowledge about their supply during the Iron Age and later periods, in contrast, remains limited, even if it has improved recently. This paper presents the results of a pilot project investigating the possible sources of lead and copper available to Egypt during the Late Period (664–332 BCE), a period of intense contact and exchange between Egypt and the Mediterranean world.In the context of this research, a wide range of artefacts from Naukratis, a major cosmopolitan trading hub in the Western Nile Delta founded in the late 7th century BC, were analysed to determine their chemical composition and lead isotope ratios. They mostly consist of metal finds—including a crucible slag—but also some locally produced faience objects which used lead and copper to colour the glaze. Additional samples include metal objects and lead ores from Tell Dafana, a Late Period settlement in the Eastern Delta, and contemporary Egyptian or Egyptianizing bronzes from Cyprus.A total of 39 objects were analysed with a combination of lead isotope and elemental analysis, yielding surprising results for the likely origins of the copper. While Cyprus, an expected source for copper, is identified for one object, the copper deposits from Faynan or from northwestern Anatolia offer the best match for most finds, including those found in Cyprus.The lead analysed seems to originate from a variety of mines, particularly from Laurion in Attica, and mines in the northern Aegean and/or northwestern Anatolia, with one example possibly from a lead‑silver mine located in central Iran. The multiplicity of lead sources reflects the complexity of international trade in the Eastern Mediterranean at the time.The study offers a valuable insight into the trade networks of Egypt and, by extension, the whole of the ancient Mediterranean. A larger-scale project investigating objects from a wider range of sites in the Eastern Mediterranean world could revolutionize our understanding of metal trade and concomitant economic, political and social developments in the first millennium BC.

Delineating the origin of Pb and Cd in the urban dust through elemental and stable isotopic ratio: A study from Hangzhou City, China

Urban dust (UD) is one of the main sinks of heavy metals in urban environments; however, the sources of these heavy metals are quite difficult to identify. A total of 78 UD samples were collected bi-monthly from October 2012 to August 2013, including 13 sites from three functional areas (residential areas, city parks, and main roads) and the Botanic Garden as a control district. The metal ratios and lead isotopic ratios combined with correlation analysis were used to identify the sources of Pb and Cd in the UD samples. In the scatter plot of Cd/Mn vs Pb/Mn, the dust samples could be classified into four groups showing their different sources and characteristics. Lead isotopic composition analysis indicated that coal combustion was the main source of Pb for residential dusts, while automobile exhaust emission for road dusts. Correlation analysis revealed that the abraded paints was a main contribution of Cd in UD, especially those in city parks. The research provides a useful method of combining multiple approaches to identify sources of metal elements in UD.

Invisible connections. Early Dynastic and Old Kingdom Egyptian metalwork in the Egyptian Museum of Leipzig University

An assemblage of ancient Egyptian metalwork from the Early Dynastic and Old Kingdom periods, currently in the Egyptian Museum of Leipzig University (Germany), has been studied using a wide range of available archaeometallurgical methods. The 3rd millennium BC Egyptian copper metallurgy is known only superficially until now. The data are interpreted in the framework of the known and reconstructed distribution networks of ancient Egyptian society. The production technology of the objects has been examined. The lead isotope analyses have made it possible to discuss the origin of the ore used for the production of Old Kingdom metalwork for the first time. A rather surprising presence in the Early Dynastic assemblage of object similar in isotopic ratios to Anatolian Early Bronze Age metalwork is discussed.

Copper for the afterlife in Predynastic to Old Kingdom Egypt: Provenance characterization by chemical and lead isotope analysis (RMAH collection, Belgium)

Copper for the afterlife in Predynastic to Old Kingdom Egypt: Provenance characterization by chemical and lead isotope analysis (RMAH collection, Belgium)

Copper ingots from a probable Bronze Age shipwreck off the coast of Salcombe, Devon: Composition and microstructure

The seabed site of a probable Bronze Age shipwreck off the coast of Salcombe in south-west England was explored between 1977 and 1982 and from 2004 onwards. Nearly 400 objects including copper and tin ingots, bronze artefacts/fragments and gold ornaments were found, typologically dating either to c. 1300–1150 BC or 1000–800 BC. The 280 copper and 40 tin plano-convex ingots and ingot fragments represent the largest discovery, measured by total weight as well as by quantity, of plano-convex or bun ingots in northwest Europe. The Salcombe copper ingots provided a wonderful opportunity for the technical study of copper ingots in a probable shipwreck context, as opposed to terrestrial contexts of deliberate deposition. The chemical composition of 25 plano-convex copper ingots was determined using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Two artefacts from the site were also analysed for comparison with the ingots. Following the compositional analysis, a microstructural study was carried out on ten Salcombe copper ingots selected to cover those with different sizes, shapes and variable impurity levels using metallography and scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDS).All the analysed copper ingots are of unalloyed copper with low levels of impurities. Sulphide inclusions are present in all samples and bulk sulphur contents are of 0.32–0.79% in the ingots but lower in the artefacts. The Salcombe ingots were found to have a quite similar impurity pattern to the Hertford Heath (England) ingots (except for iron content). They are distinctly different from the Uluburun ingots, and, to a lesser degree, from Sardinian ingots. The results are inconclusive as to how the Salcombe ingots were made. On the one hand, the very low concentration of iron and the absence of cuprite inclusions suggest that the ingots were primary smelting products of the primitive smelting process rather than produced from re-melting or refining of primary smelting lumps. On the other hand, the dense metal with very low porosity suggests the product of refining and re-casting operations under reducing conditions. However, the small ingots are not likely to have resulted from breaking of large ingots. The chemical compositions of the Salcombe ingots point to British or Western European sources although the connection with other regions cannot be excluded for some of the ingots. Further studies including lead isotope analysis are needed to address the question of provenance of the copper ingots, which would contribute to the re-emerging debates surrounding the European Bronze Age metal trade.

Pb Isotope Mapping of Paleoproterozoic Gneisses in the SW Grenville Province: Evidence for a Cryptic Continental Suture

New whole-rock lead (Pb) isotope analyses are presented in this study for granitoid orthogneisses from the Southwest Grenville Province in Ontario and Western Quebec. These data are used to test the location of a cryptic Archean-Proterozoic suture proposed on the basis of neodymium (Nd) isotope mapping. Immediately south of the inferred suture boundary, Pb isotope results show a crustal component derived solely from a juvenile Paleoproterozoic mantle source. These data are distinctly different from the reworked Archean craton to the northwest and strongly support the boundary derived from Nd isotope data. Pb signatures in the Paleoproterozoic crust suggest a southerly increase in magmatic reworking due to intensive plutonism during the late Paleoproterozoic and early Mesoproterozoic periods. The accretion of a juvenile arc to the Archean margin during the Penokean event (ca. 1.85 Ga) would have triggered subduction-zone reversal and the development of a long-lived ensialic arc on the composite margin. This was expressed as a 1.75 Ga Killarnian magmatic event and subsequent early Mesoproterozoic magmatism. This tectonic model for the Southwest Grenville Province shows that its crustal evolution is consistent with the Paleoproterozoic Makkovik-Ketilidian Orogen of Labrador and Southern Greenland. Hence, the application of whole-rock Pb isotope data in conjunction with Nd model ages provides data useful for mapping the extent of crustal terranes of differing age, which is essential for modeling the tectonic evolution of complex ancient accretionary orogens.

Lost in the South: A Roman Copper Ingot from the area of Tarragona in the Baetica

A Roman copper ingot recovered from a wreck located in the border region of the provinces of Malaga and Cadiz is presented in the following contribution. With a diameter of 45 to 53 cm and a weight of 75.4 kg it is one of the heavier specimens. Presumably the abbreviation of a name and the indication of its weight were incised near the rim of the bottom. Lead isotope and trace element analysis suggest a provenance not from mines in southern Hispania, but from the polymetallic ores of the Catalunya region in northeastern Spain.

Metalurgia prehistórica en Tierras de Antequera y su contexto andaluz

Tierras de Antequera is located between the two main research foci of the Iberian Late Prehistory: the Southwest and the Southeast. This peripheral nature, coupled with a shortage of metallurgical evidence in the area, contributed to generalize the idea that Malaga was systematically importing metals from other regions. However, the Project Investigacion Arqueometalurgica de la Provincia de Malaga showed the existence of both copper outcrops potentially exploitable by prehistoric societies, as well as significant archaeometallurgical by-products in several sites from the 3rd and 2nd millennium bc. Moreover, recent archaeological excavations have documented prehistoric metallurgical by-products in the core of Tierras de Antequera. This fact has forced us to reassess the topic and rethink our hypothesis on the models of copper production by these communities. In this paper we review prehistoric archaeometallurgical evidence, present new elemental composition information as well as lead isotope analyses and, in light of recent findings, we approach the socio-economic role that copper production played in its broader Andalusian context and especially in relation to the two main metallurgical foci.

Economic Geology, Mining Archaeological and Archaeometric Investigations at the Veshnaveh Ancient Copper Mine, Central Iran

The Veshnaveh ancient copper mine is located in the middle of the Orumieh-Dokhtar volcanic belt in north central Iran and is hosted by middle-upper Eocene volcanic and sedimentary rocks. The focus of this paper is the investigation of ore and rock samples from Veshnaveh using diverse geochemical and mineralogical methods including ore microscopy, scanning electron microscopy, inductively coupled plasma mass spectrometry and lead isotope analysis in order to better understand the nature of mineralization. The results were then compared with the results from the ancient metallurgical relics from some key sites in central Iran including Tappeh Sialk, Arismān, Tappeh Sarm and Jamkarān. The results show the Veshnaveh deposit is a Manto type mineralization whose ore has been possibly used from the Middle Bronze Age until the early Iron Age by surrounding communities.

Roman Silver Objects from the Ancient Kingdom of Kartli (Caucasian Iberia) in Georgia (Mtskheta, Dedoplis Gora [Kareli district]) – a Lead Isotope Investigation

Seven silver objects from antique Georgia, e. g. a raven and a goddess Diana sculpture, have been archaeometallurgically investigated. Six are dated into the 1st century AD and have been found in a burnt down palace at “Dedoplis Gora”. They are all strongly affected by a fire which was caused by an earthquake in 80 AD. Another object of study is a fragmented silver box of the 3rd century AD, excavated at Mtskheta, the old capital of the Kingdom of Kartli. All objects come from a time of great political influence from Rome. The provenance investigation by lead isotope analysis points not only to three different sources in the Roman Empire, the Central Balkans, the Cévennes (Massif Central) in France and the Pangeon Mountains in northern Greece, but also to lead-silver mines in Iran.

Archaeometallurgical investigations of a Viking brass ingot hoard from the Hedeby Harbor in northern Germany

A hoard of twenty-five copper-alloy bar ingots was discovered on the edge of the harbor of the Viking-period settlement of Hedeby during excavations in the 1980s. The typology and the location of the hoard indicate a date in the early 9th century AD. Each bar ingot was sampled and analyzed by mass spectrometry and the elemental compositions and lead isotope ratios were used to assess the degree of standardization and to explore the question of source. The results show that the bars are made of a freshly produced, standardized, high-quality brass alloy. The lead isotope analysis indicates that the brass is not consistent with the ore deposits of the Rhine area, commonly assumed to be the source of brass in northern Europe in the Viking Age. The brass bar ingots are possibly products originating from the Balkans or Andalusia, and thus, provide further evidence of the importance of long-distance trade of raw materials in the early Middle Ages.

Copper Production and Trade in the Niari Basin (Republic of Congo) During the 13th to 19th Centuries ce: Chemical and Lead Isotope Characterization

In Central Africa, copper ore occurs in only a few locations and copper appears to have been a scarce commodity in the past—contrary to iron, which is attested more widely and earlier in the sub‐Saharan archaeological record. This paper presents the first detailed characterization of an early copper‐working region in Central Africa. Located along the southern border of the Republic of the Congo, the Niari Basin has revealed several copper production sites ranging from the 13th to the 19th century ce. The evidence, specifically in the Mindouli, Mfouati and Boko‐Songho areas, includes various production remains as well as different types of copper ingots and artefacts. In the context of a broader copper technology study, the chemical and lead isotope characteristics of the ore deposits in this region are presented. The results of the chemical and lead isotope analyses of copper objects and production remains from archaeological sites are then interpreted against this geological background data, with an emphasis on copper provenance features. Combining these results with archaeological and historical evidence for regional metallurgical activity, new and significant insights are given on the production of copper in the Niari Basin, emphasizing the potential of this research for forthcoming work on copper use and trade in a wider Central African context.

Application of Kernel Density Estimates to Lead Isotope Compositions of Bronzes from Ningxia, North‐West China

The aim of this paper is to apply kernel density estimates (KDEs) to the visualization and interpretation of lead isotope data from bronze assemblages found along the northern border of central China, here designated as the Arc. New lead isotope analyses of 30 leaded tin–bronze artefacts from the Wangdahu cemetery (c.500–300 bc) in the Ningxia Hui Autonomous Region, north‐west China, provide the basis for the discussion. By using multivariate KDEs and the calculated likelihood of the overlap, the present work shows that the Wangdahu objects feature a unique linear array of isotope ratios, representing an important element of overall bronzes from the Arc in the first millennium bc. This characteristic isotope signature is fundamentally different from that of Dajing ores in north‐east China, as well from that of early Qin bronzes in Shaanxi and Gansu provinces. This suggests that a variety of metal resources were utilized by peoples living in the Arc. The KDE approach thus proves effective at presenting and comparing lead isotope data.

Lead Isotope Analysis of Tooth Enamel from a Viking Age Mass Grave in Southern Britain and the Constraints it Places on the Origin of the Individuals

Lead analysis of tooth enamel from individuals recovered from a Viking Age burial pit in southern England provides further evidence for their childhood origins outside Britain. All except one of the men have very low Pb concentrations that exclude anthropogenic Pb exposure. Strontium and oxygen isotope compositions identify a core group of men who have Pb isotope compositions of 208Pb/206Pb = 2.065 ± 0.021 (n = 20, 2SD) that, when compared with data from European soils, appear to exclude a childhood in the Scandinavian countries of Norway, Sweden and Finland, whereas areas of Northern continental Europe cannot be excluded.

Ore genesis of the Wusihe carbonate-hosted Zn-Pb deposit in the Dadu River Valley district, Yangtze Block, SW China: evidence from ore geology, S-Pb isotopes, and sphalerite Rb-Sr dating

The Wusihe carbonate-hosted Zn-Pb deposit (3.7 Mt. Zn + Pb at a grade of 8.6% Zn and 2.0% Pb) is the largest deposit in the Dadu River Valley district of the Sichuan-Yunnan-Guizhou metallogenic province of southwest China. Three types of orebodies occur: (1) stratiform, banded and lamellar, within dolomite of the Neoproterozoic Dengying Formation; (2) vein type; and (3) breccia type. Four stages of mineralization are distinguished: (i) pyrite stage, (ii) pyrite-pyrrhotite-galena-sphalerite-bitumen stage, (iii) sphalerite-galena stage, and (iv) bitumen-calcite stage. Sphalerite and galena from stages II and III show δ34S ranges from +7.1 to +9.7‰ and +9.1 to +13.1‰, respectively. High-precision in situ lead isotope analyses of sulfides show 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb ratios of 37.938 to 38.336, 15.579 to 15.682, and 17.951 to 18.195, respectively, which suggest a mixing of lead from the basement and the host rocks. Rb-Sr isotope analyses for six sphalerite samples of stage II yielded an isochron age of 411 ± 10 Ma (MSWD = 1.4). Combining all available ore geology and geochemical data, together with fluid inclusion data reported previously, we suggest that the Wusihe deposit is a Mississippi Valley-type (MVT) deposit.