The Origin and Archaeometallurgy of a Mixed Sulphide Ore for Copper Production on the Island of Kea,Aegean Sea,Greece

At the hill of Agios Symeon, on the island of Kea, Aegean Sea, Greece, ancient metallurgical slags with a high Pb–Zn–Cu content have been found. Thermodynamic simulations have been carried out, using the FactSage? thermodynamic database computing system, with a view to understanding the ancient metallurgical processes that produced the observed slag compositions and morphologies. The simulations demonstrate that the slag samples resulted from Cu‐making processes. It would thus appear that mixed ores were used, containing Cu₂S–FeS–PbS with significant amounts of sphalerite (ZnS) as impurity. The roasted ores were reduced at relatively high oxygen potentials at ～1125°C to form Cu containing low levels of Pb, Fe and Zn.     

The mineral wealth of ancient Arabia and its use I: Copper mining and smelting at Feinan and Timna – comparison and evaluation of techniques, production, and strategies

Near Eastern fieldwork in mining archaeology and archaeometallurgy began at Timna (Israel) in the 1960s and 1970s and continued in Feinan (Jordan) in the 1980s and 1990s. For the first time, Bronze Age copper mines were excavated and cleared and importance was given to the slag recovered. At both sites copper was produced for over 5000 years, from the Chalcolithic to the Mamluk periods. Although the broad outlines of technical development can be traced, much remains to be learned in future studies.     

A preliminary study on the role and implication of plate-type iron artifacts in the ancient iron technology of Korea

Special iron objects in the form of a narrow plate with a fan-shaped blade on one or both ends, but with a substantial variation in shape and size, have continually been excavated from ancient historical sites located in the southern part of the Korean peninsula. The frequency and abundance of their excavation imply that they must have played a crucial role in the initial shaping of the Korean iron industry. Little is known, however, of their intended purposes or the exact engineering processes applied in their production. Speculation suggests that they might have been used as currencies or intermediate materials for the making of finished products. This study examined the microstructures of three such iron objects from the Korean Three Kingdoms Period (ca. 300–600 AD). It was determined that they were made of low carbon iron generally containing a number of non-metallic inclusions, with hints of surface carburization particularly at the ends of the plates. These results reveal the likely presence of an iron technology based primarily on the bloomery technique as opposed to the Chinese style of iron-making based on cast iron technology, which was also in use in ancient Korea.     

Large-scale 2nd to 3rd century AD bloomery iron smelting in Korea

Iron production in Korea has traditionally been seen in the shadow of developments in cast iron technology in China, with limited indication for a northern influence via Russia’s Maritime Province. The possibility of the existence of bloomery iron production in ancient Korea has been little explored, and relevant discussion is fraught with speculations based primarily on the early use of cast iron. The recent excavation of a site in South Korea recovered substantial amounts of slag providing direct evidence of bloomery smelting. The accelerator mass spectrometric dating of burnt wood from inside one of the slag pieces showed that the site was in use in the early 3rd century AD or earlier, which is in agreement with the assessment based on ceramic typology. The traits of a bloomery process evident in the slags’ microstructure, shape, composition and excavation context are discussed along with the implications for historical iron technology in Korea, where cast iron and the influence from China have been overly emphasised.     

Evaluating copper isotope fractionation in the metallurgical operational chain: An experimental approach

Until today, raw material information of copper (Cu) objects is mostly gained from impurities and trace elements and not from the Cu itself. This might be obtained using its stable isotopes. However, isotopic fingerprinting requires the absence of fractionation during the smelting process. The Cu isotope evolution during outdoor smelting experiments with Cu sulphide ore was investigated. It is shown that external materials, in particular furnace lining, clay, manure and sand, alter the isotopic composition of the smelting products. Cu isotopes are fractionated within low viscosity slag derived from matte smelting. The produced metallic Cu has a Cu isotope signature close to the ore.     

Pre‐Industrial Iron Smelting and Silver Extraction in North‐Eastern Greece: an Archaeometallurgical Approach

In contrast to Western Europe's well‐documented contribution to global industrialization, Eastern Europe has not received adequate attention. This paper addresses this asymmetry by defining a secure socio‐technical framework for the development of metallurgical technology in one of the most important mineralized zones in Eastern Europe, namely the uplands of north‐eastern Greece. The interplay of technological innovation, geography and social process has made this region central in European political history from the Classical and Roman periods up to recent times. Metal procurement has been crucial particularly between the 15th and 19th centuries ad, when armed conflicts escalated across the Balkans and the high inflation throughout Europe increased the demand for raw materials from the East. Field data from north‐eastern Greece and instrumental analysis corroborate the concept of iron extraction during this period from complex ores that were potentially used for their precious metals contents as well. Chemical analysis of slag points to iron bloomery processes, while analysis of respective residues (speiss) reveals significant concentrations of silver and thus testifies to the extraction of precious metals. This study addresses concerns that preoccupy political and technological minds today, and provides a context for understanding the effects of changing attitudes to the environment, social development, consumption and natural resources.     

Investigating the production provenance of iron artifacts with multivariate methods

The quest for suitable data, data treatments and statistical methods for identifying the provenance of iron artifacts has led to a variety of analytical strategies. Researchers working on the problem have been slow to develop or adopt the use of multivariate statistical techniques, despite their successful implementation in other archaeomaterials sourcing frameworks. This paper explores the analytical potential of a comprehensive multivariate statistical strategy for identifying the primary production origins of bloomery iron artifacts using bulk chemical analyses of bloomery smelting slag and slag inclusions in iron artifacts. This strategy includes a multivariate model for identifying distinct slag inclusion types introduced during smelting and refining. Principal component analysis and linear discriminant analysis are then applied to smelting slag training sets to create multivariate provenance fields, the chemical distributions of which are defined by kernel density estimation. Single and multi-group evaluation methods are examined. Appropriate data transformations are discussed to facilitate the projection of the chemistry of “unknown” slag inclusions into the multidimensional space generated by the smelting slag groups of known provenance. The efficacy of this strategy is demonstrated through its application to a previously examined data set derived from three iron production experiments and a published archaeological example. Results indicate that an appropriately designed multivariate strategy can be an effective tool for evaluating provenance hypotheses for bloomery iron artifacts.     

Identifying stone tools used in mining,smelting, and casting in Middle Bronze Age Cyprus

Abstract

Metallurgical production sites are often difficult to identify in the archaeological record because ore beneficiation and slag processing in the past involved the use of ground stone tools that were similar to those used in other contexts to prepare cereals and foods. Analysis of the ground stone assemblage from a Middle Bronze Age copper mining and production site at Ambelikou Aletri in Cyprus provided an opportunity to distinguish industrial and domestic ground stone tools and to identify the types of tools used in different stages of metal production. A comparison of tool morphologies, raw materials, and wear and breakage patterns from Ambelikou Aletri with those from contemporary domestic contexts, suggests that distinctions in the nature and structure of industrial and domestic tool kits do exist and those distinctions have an important role to play in identifying mining, smelting, and casting sites in the future.     

A new approach for geomagnetic archaeointensity research: insights on ancient metallurgy in the Southern Levant

We present results from an archaeointensity investigation based on a relatively unexploited recording medium, copper slag deposits. Together with a recently improved experimental design for the archaeointensity experiment, we demonstrate the applicability of this medium, as well as other archaeometallurgical artifacts, for the study of the ancient geomagnetic field intensity. In addition to archaeointensity data from well-dated archaeological contexts, we obtained reliable archaeointensity results from poorly dated or contentious archaeometallurgical sites in the Southern Levant. These results shed new light on the dating of these sites, among them the copper smelting installation of Timna 39b – a site that has important implications for the beginning of metallurgy during the fifth millennium BCE. The paper also aims to introduce archaeointensity research to the archaeologist scholar, and to encourage further collaboration between the disciplines in future research.     

Microstructural and elemental analyses of slags excavated from Xuxiebian iron‐smelting site,Sichuan, China

Xuxiebian is an iron‐smelting site located in Pujiang county of Sichuan province, China. Two excavations were carried out in 2007 and 2011, and four bowl‐shaped furnaces were excavated. Ten slag samples from the site were prepared and analysed. The present paper reports the results of metallographic and elemental examination of the specimens. It is concluded that both pig‐iron‐smelting and refining process were applied at the Xuxiebian site, and the bowl‐shaped furnaces are possibly refining furnaces. The function of the site was probably to produce pig iron and refine the pig iron into wrought iron.