On the origins of extractive metallurgy: new evidence from Europe

The beginnings of extractive metallurgy in Eurasia are contentious. The first cast copper objects in this region emerge c. 7000 years ago, and their production has been tentatively linked to centres in the Near East. This assumption, however, is not substantiated by evidence for copper smelting in those centres. Here, we present results from recent excavations from Belovode, a Vin?a culture site in Eastern Serbia, which has provided the earliest direct evidence for copper smelting to date. The earliest copper smelting activities there took place c. 7000 years ago, contemporary with the emergence of the first cast copper objects. Through optical, chemical and provenance analyses of copper slag, minerals, ores and artefacts, we demonstrate the presence of an established metallurgical technology during this period, exploiting multiple sources for raw materials. These results extend the known record of copper smelting by more than half a millennium, with substantial implications. Extractive metallurgy occurs at a location far away from the Near East, challenging the traditional model of a single origin of metallurgy and reviving the possibility of multiple, independent inventions.     

Reassessment and new data on the diachronic relationship of Thassos Island with its indigenous metal resources: a review

The extraction of mineral ores and its associated metal production has been a persistent element of the economy on Thassos Island since prehistoric times. As early as the Upper Palaeolithic, around 20,000 years ago, ochre had been mined and used for painting, while early silver extraction is attested during the Final Neolithic (early fourth millennium BC). Copper production and alloying becomes an important activity in the coastal settlements of the island during the third and second millennia. The inception of iron metallurgy has been seen in association with copper smelting as confirmed by analyses on slag found in Early Iron Age upland cemeteries. With the arrival of the Greek colonists around 650 BC, intensification in silver and gold extraction became paramount for further economic expansion. This deep history in the use of Thassian metals is being reviewed based on archaeological findings and archaeometallurgical research of the last three decades, while new analytical data on Early Bronze Age copper smelting at Aghios Antonios are being presented.     

‘DE CAERIMONIAE’ TECHNOLOGICAL CHOICES IN COPPER‐SMELTING FURNACE DESIGN AT EARLY BRONZE AGE CHRYSOKAMINO,CRETE*

The excavation of a number of Early Bronze Age sites in the Aegean has recovered perforated ceramic fragments. Archaeometallurgical analysis of slag adhering to these fragments indicates that they are the remains of copper‐smelting furnaces. Despite compelling analytical data supporting this identification, no attempt has been made, thus far, to establish how these unusual furnaces may have operated. The use of perforations is poorly understood and can be considered a counter‐intuitive solution for the reduction of oxidic copper ores. The experiments reported here explore the possible technological choices made by the ancient metalworkers of Chrysokamino to ensure the effective reduction of copper minerals. Temperature data and slag samples were obtained to ascertain the technical performance of the furnace structure with, and without, perforations. Possible reasons are given for the use of a perforated design, and the implications of such technological choices are considered.     

The production of speiss (iron arsenide) during the Early Bronze Age in Iran

In this paper, analyses of some unusual slag samples from the prehistoric site of Tepe Hissar in northeastern Iran are presented. These slags are the remains of a five-thousand-year-old pyrotechnological process that produced speiss, a quasi-metallic material usually formed as an accidental by-product of copper or lead smelting. We argue that the “speiss slags” from Tepe Hissar suggest the intentional production of iron–arsenic alloy (“speiss”) in prehistory. Why the Tepe Hissar metalworkers produced speiss is a question that requires further investigation, but our preliminary assessment suggests that it was to provide arsenic as an alloying component for arsenical copper, the preferred copper alloy during much of the Early Bronze Age in Iran, and widely used across the ancient world. This recognition significantly advances our understanding of the early stages of metallurgy in the Old World.     

5,000 years old Egyptian iron beads made from hammered meteoritic iron

The earliest known iron artefacts are nine small beads securely dated to circa 3200 BC, from two burials in Gerzeh, northern Egypt. We show that these beads were made from meteoritic iron, and shaped by careful hammering the metal into thin sheets before rolling them into tubes. The study demonstrates the ability of neutron and X-ray methods to determine the nature of the material even after complete corrosion of the iron metal. The iron beads were strung into a necklace together with other exotic minerals such as lapis lazuli, gold and carnelian, revealing the status of meteoritic iron as a special material on a par with precious metal and gem stones. The results confirm that already in the fourth millennium BC metalworkers had mastered the smithing of meteoritic iron, an iron–nickel alloy much harder and more brittle than the more commonly worked copper. This is of wider significance as it demonstrates that metalworkers had already nearly two millennia of experience to hot-work meteoritic iron when iron smelting was introduced. This knowledge was essential for the development of iron smelting, which produced metal in a solid state process and hence depended on this ability in order to replace copper and bronze as the main utilitarian metals.     

The potential of stable Cu isotopes for the identification of Bronze Age ore mineral sources from Cyprus and Faynan: results from Uluburun and Khirbat Hamra Ifdan

Copper isotope ratios differ between hypogene sulfidic, supergene sulfidic and oxidized ore sources. Traditional lead isotope signatures of ancient metals are specific to deposits, while Cu isotope signatures are specific to the types of ore minerals used for metal production in ancient times. Two methodological case studies are presented: First, the mining district of Faynan (Jordan) was investigated. Here, mainly oxidized copper ores occur in the deposits. The production of copper from Fayan’s ore sources is confirmed by the measurement of the Cu isotope signature of ingots from the Early Bronze Age metal workshop from Khirbat Hamra Ifdan. Based on our results illustrating differences in the Cu isotope composition between the ore mineralizations from Timna (Israel) and Faynan, it is now possible to determine these prehistoric mining districts from which copper artifacts originated by combining trace elements and Pb isotopes with Cu isotopes. The second case study presents data on Late Bronze Age copper production in Cyprus. Oxhide ingots from the shipwreck of Uluburun (Turkey) were tested for their lead isotope signatures and assigned to Cypriot deposits in the recent decades. The oxhide ingots from Uluburun show a Cu isotope signature which we also found for oxidized copper ores from Cyprus, while younger oxhide ingots as well as metallurgical slag from the Cypriot settlements Kition and Enkomi show a different signature which might be due to the use of sulfidic ore sources from a greater depth of deposits. We assert that there could be a chronological shift from oxidized to sulfidic ore sources for the copper production in Cyprus, requiring different technologies. Therefore, Cu isotopes can be used as a proxy to reconstruct mining and induced smelting activities in ancient times.     

Origins of Specialization: The Ceramic Chaîne Opératoire and Technological Take‐Off at Vinča‐Belo Brdo,Serbia

This paper presents scientific analyses of Neolithic pottery from Miloje Vasi?’s 1930 –34 excavations at Vin?a‐Belo Brdo, which has long been a key site in south‐eastern European prehistory. Results show a series of changes in the chaîne opératoire of pottery production, both between the early Neolithic Star?evo and middle–late Neolithic Vin?a periods, and between Vin?a A and Vin?a B phases. Unlike in Star?evo assemblages, Vin?a pottery fabrics probably served specific functions, but cult objects (an anthropomorphic figurine and several prosopomorphic lids) were made locally using the same raw materials and technology used to make Vin?a fine ware. In contrast to the uniformity of Star?evo pottery technology, Vin?a pottery production was geographically diverse and evolved over time. Higher firing temperatures of Vin?a pottery apparently preceded the development of metallurgy by more than a century.     

SERIPHOS SURFACES: A STUDY OF COPPER SLAG HEAPS AND COPPER SOURCES IN THE CONTEXT OF EARLY BRONZE AGE AEGEAN METAL PRODUCTION

Kephala and Phournoi, on the island of Seriphos, add to a growing number of EBA metal production sites identified in the south‐central Aegean. Analytical examination of samples from the two sites addressed the technological parameters of the copper smelting process, indicating the use of mixed oxidic and sulphidic copper–iron ores to produce unalloyed copper with minute copper sulphide inclusions. A preliminary geological reconnaissance of the island identified several small copper mineralizations, one of them close to the site of Kephala. Nevertheless, the ore sources used remain unclear. Comparisons are made with other contemporaneous neighbouring smelting sites.     

Isotopic and technological variation in prehistoric Southeast Asian primary copper production

The ‘Southeast Asian Lead Isotope Project’ (SEALIP) is intended to provide reliable geochemical proxies for late prehistoric through early historic (2nd/1st millennium BCE and 1st millennium CE) local, regional, and inter-regional social interactions, in an archaeological arena lacking established ceramic typologies with which to cross modern national boundaries. We present lead isotope characterisations of the three currently known Southeast Asian prehistoric primary (mining/smelting) copper production centres: Phu Lon and the Khao Wong Prachan Valley in Thailand, and the recently discovered Xepon complex in Laos. Kernel Density Estimation shows that these production centres can be clearly distinguished isotopically, as such fulfilling the core tenet of the ‘Provenance Hypothesis’ (Wilson and Pollard, 2001: 508) and permitting SEALIP to proceed as a research programme tracing regional copper/bronze/lead exchange and provenance patterning. In addition we provide a provisional technological reconstruction of copper smelting processes at Phu Lon to complement our more established understanding of the Khao Wong Prachan Valley. Combined lead isotope and technological datasets allow us to tentatively identify trends in the evolution of Southeast Asian metal technologies and of regional social perceptions of metal exchange.     

A STATISTICAL STUDY OF THE IMPURITY OCCURRENCES IN COPPER ORES AND THEIR RELATIONSHIP TO ORE TYPES

A study of the impurity distributions in copper obtained from various ores shows no significant correlations between the impurity distributions. A test of 390 samples of copper obtained from various ores shows that more than 75% of copper samples can be correctly identified as coming from either simple copper metal ores, oxidized ores or more complex reduced ores thereby yielding information on the metallurgical capabilities of the society smelting the ores.     

ANGLO-SAXON COPPER ALLOYS FROM LECHLADE, GLOUCESTERSHIRE

Summary. A range of copper-alloy artefacts from the early Anglo-Saxon cemetery at Lechlade were analysed using X-ray fluorescence. There were few pure bronzes or brasses in the assemblage and most alloys contained significant amounts of zinc, tin and lead in variable ratios. In view of the current theory that supplies of new metals and ores were limited and Anglo-Saxon metalworkers normally used scrap metal, the compositions were used to assess the techniques of the craftsmen supplying this community. It is concluded that re-use of copper alloys was prevalent but that metals were selected quite carefully for particular applications, with regard to the metallurgical characteristics required.     

Silver lining: evidence for Inka silver refining in northern Chile

Prehistoric silver purification using lead cupellation has been documented in multiple places throughout the Andes, but direct evidence of the Inka use of this technology has remained elusive. In this study, we use X-ray fluorescence, scanning electron microscopy, and electron-microprobe analysis to document direct evidence of Inka period (AD 1400–1532) silver purification using lead cupellation in the Tarapacá Valley of northern Chile. Local metalworkers used wind-driven huayra furnaces to produce pure lead metal, sustaining temperatures of ca. 900–1100 °C to smelt lead-bearing ores that may have included galena. The lead metal was then used in open-vessel cupellation of silver-bearing ores, some of which may have been cupriferous and derived from the nearby Inka mines at Huantajaya. Phase analyses of the slagged interiors of bowl-shaped ceramic vessels used for cupellation indicate that the metalworkers maintained the oxidizing environment and temperatures between 800 and 1100 °C requisite for cupellation. We argue that the Inka introduced this technique to Tarapacá metalworkers. The absence of finished silver artifacts in local valley contexts suggests that the refined silver was removed from the valley for use elsewhere in the empire.     

Direct chronometry (14C AMS) of the earliest copper metallurgy in the Guadalquivir Basin (Spain) during the Third millennium BC: first regional database

The characterisation of copper metallurgy in the Third millennium BC in the Southeast of the Iberian Peninsula as a simple and technological process on a domestic scale was the central axis that sustained a belated, underdeveloped appreciation for the Prehistory of the Iberian Peninsula and Western Europe dependent on the origin of social complexities. Nevertheless, this characterisation was incomplete since it was based more on the contexts of consumption than those of production and in territories used for agricultural rather than for mining purposes. Above all, however, it was incomplete because it lacked a precise spatial and temporal framework that evaluated the variability of the behaviours it articulated.To overcome these deficiencies, we have developed a systematic programme of interdisciplinary research aimed at documenting and dating, through the use of ¹⁴C AMS, the direct contexts of copper production of eight settlements that cover the populational variability (from 300 to 0.25 ha of surface area), chronology (between c. 3000 BC and c. 2000 BC), economic (settlements dedicated to mining, agriculture, etc.) and territorial along the axis of the backbone of the most fertile soils and primary (main) supplies of copper in the Iberian Peninsula: the Guadalquivir Basin.Results consist of the first systematic database, with sixty-six precise, direct radiocarbon dating of the metallurgical production of copper during the Third millennium BC, in the Iberian Peninsula and Western Europe. At the same time, it presents a variability of contexts (e.g. household, workshop, partial-time, full-time, factory, smelting quarter, etc.), in both time and space, affording a precise evaluation of social and territorial variability of behaviours that the production of copper shows us, a new historical explanation and the link between this and the development of social complexity.     

COPPER AND BRONZE DURING THE ENEOLITHIC AND EARLY BRONZE AGE: A METALLOGRAPHIC EXAMINATION OF AXES FROM THE NORTHALPINE REGION*

This paper presents the results of a metallographic examination of Eneolithic and Early Bronze Age axes from the Northalpine region of central Europe. During this period, different types of copper were in use: arsenical copper, Fahlerz copper and tin bronze. We examine if and to what extent the different properties of the metals used were known to prehistoric metalworkers and actively manipulated in the production of the axes. The development of methods of casting and smithing is discussed. Both aspects contribute to our understanding of the nature of prehistoric technological change. During the Early Bronze Age of the Northalpine region, different traditions of early metallurgy can be identified, which differ in their use of Fahlerz copper, their attitude towards tin alloying and the use made of tin bronze in the production of the axes. These traditions can only be adequately described by reference to both composition—that is, access to different types of copper as well as tin—and knowledge of the production techniques provided by metallographic data.     

Production and Consumption of Copper-base Metals in the Indus Civilization

We review the existing data sets for the production and consumption of copper-base objects at Indus sites, outline a working typology for metal objects, and provide new data from on-going analytical work on the copper assemblage from Harappa. The role of metals in the economic and social networks of the Indus tradition is examined in terms of patterns of use and technological style. We note that Indus metalsmiths apparently relied more on procurement of metal ingots or scrap than on primary ingot production through smelting, which would have affected other aspects of Indus metallurgy. Object production did not involve elaborate forms, but may have involved complex alloying. Finally, we conclude that there is no evidence for elite control of metal production, and that access to metals was relatively widespread.     

SOUTHEAST ASIA'S FIRST ISOTOPICALLY DEFINED PREHISTORIC COPPER PRODUCTION SYSTEM: WHEN DID EXTRACTIVE METALLURGY BEGIN IN THE KHAO WONG PRACHAN VALLEY OF CENTRAL THAILAND?

Southeast Asian metallurgical developments have been a focus of international academic interest since Solheim (1968 ) and Bayard (1972 ) first published bronze artefacts in claimed early/middle third millennium bce contexts from northeastern Thailand, igniting a regional ‘origins’ of metallurgy debate that has smouldered for 40 years (e.g., White and Hamilton 2009 , Higham in press ). In this paper, we present the results of a lead isotope pilot study centred on the Khao Wong Prachan Valley of central Thailand—currently Southeast Asia's only documented prehistoric copper smelting locale. These preliminary data indicate that our ongoing regional metal exchange research programme may be able to elucidate interaction networks between copper‐producing and ‐consuming societies within and beyond Southeast Asia from c. 2000 bce to c. 500 ce . Furthermore, we are able to offer tentative evidence relevant to White and Hamilton's (2009 ) ‘Rapid Eurasian Technological Expansion Model’ for the Sino‐Siberian derivation of regional metal technologies around the turn of the third/second millennium bce .     

山东莱芜嬴城遗址炼铜渣初步研究

为了解山东地区早期冶金技术的发展情况,采用扫描电子显微镜分析等方法,对莱芜赢城冶炼遗址出土的3件炉渣进行了检测。结果表明其中2件为红铜还原渣,1件为砷铜熔炼渣。由此推测该遗址铜的还原可能存在两种工序,并且掌握了利用含砷矿物"点炼"铜液得到砷铜的技术。遗址所利用的铜可能来自于北江水铜矿,砷可能来自于鲁中山区,炉渣所属的时代应与遗址出土的商周青铜器年代相近。     

Partitioning of trace elements between the ores, fluxes, slags and metal during the smelting of copper

This paper gives the results of smelting seven parcels of copper ores from well-known mining areas. The behaviour of the trace elements introduced from the ore, the fuel, and the fluxes has been investigated by analysis of the main products, metallic copper and the slags. Most of the ores were capable of giving copper of relatively high purity and therefore, in order to represent conditions believed to have existed in the Early Bronze Age, two artificial ores were made up and copper high in arsenic and nickel was obtained.The results show that it is relatively easy to smelt a wide range of copper minerals to give copper of high purity apart from iron. This latter element can be removed by careful refining. The remaining elements are present at the parts/10³ level. Wood fuel is thought to contribute little to the trace element pattern. Even if it did, it would merely reinforce the elements already contributed by the ore and flux as the timber is likely to have been grown in the immediate vicinity of the ore and will probably contain the same trace elements.Useful comparison is made between the trace element pattern resulting from these smelting runs and material from archaeological sites in the vicinity of the mining areas.     

Encounters with Iron: An Archaeometallurgical Reassessment of Early Anglo-Saxon Spearheads and Knives

Studies of early medieval weapon burials make surprisingly little mention of the material properties of the deposited weapons. How did these artefacts’ metallurgical properties, and people’s experiences making and shaping the materials from which they were made, relate to the social and ‘magical’ potential these weapons were ascribed? This article reassesses metallurgical data from fifty-two early Anglo-Saxon spearheads discovered in cemetery contexts, and 118 knives from cemeteries and settlements, and reinterprets their technological properties as a glimpse into the social experiences of their makers and users. The choices smiths made when forging these blades are visible in their surviving metallurgy, and reveal their makers’ desired outcomes — and their mixed results. The difficulties smiths negotiated while forging iron shaped the social biographies that blades accumulated after leaving the workshop. By studying the materials from which these artefacts were made, and the practices of the makers who struggled to shape and control them, we may better appreciate the social agency and value ascribed to material objects in the early medieval period.     

EARLY BRONZE AGE TIN PROCESSING AT KESTEL/GÖLTEPE,ANATOLIA

Chemical analysis of statistically significant numbers of samples including minerals, sediments, soil, host rock as well as powdered materials, crucible accretions and metal artefacts revealed information about the distribution of cassiterite at Kestel and the tin smelting processes that took place at Göltepe c. 2600 BC. Using the ancient technique of vanning for the isolation of tin ore (cassiterite), followed by assaying by blowpipe/charcoal block, as well as crucible smelting with a blowpipe, good tin metal suitable for alloying with copper to make bronze was obtained. There is every indication that tin was mined and smelted in the Early Bronze Age at the Kestel/Göltepe sites.