Derrycarhoon: a Later Bronze Age copper mine in South-west Ireland

Archaeometry, 2005

In recent years archaeological finds and scientific analyses have provided increasing evidence for a very early beginning of copper production in the rich mining area of the Tyrolean Alps. The earliest findings derive from an excavation of a multi-phase settlement on the Mariahilfbergl in Brixlegg, which revealed evidence that a small amount of fahlores, probably of local provenance, was at least heated if not even smelted there in the Late Neolithic Münchshöfen culture (the second half of the fifth millennium BC). However, most copper finds of this horizon consist of low-impurity copper that most probably derives from Majdanpek in Serbia. This long-distance relationship is corroborated by typological features that link some aspects of the Münchshöfen culture with the Carpathian basin. Thus it is not yet clear if, at Brixlegg, actual copper production took place or, rather, an experimental treatment of the local ores. The typical fahlore composition, with arsenic and antimony in the per cent and silver and bismuth in the per mille ranges, appears in quantity only in the Early Bronze Age. Many thousands of Ösenringe are known from many central European Early Bronze Age sites, with a chemical composition typical of fahlores. At Buchberg near Brixlegg, a fortified settlement with slags from fahlore smelting proves that the local ores were indeed exploited. The lead isotope ratios of Ösenringe from the Gammersham hoard in Bavaria, which consist of fahlore copper, confirm this and suggest that copper mining and production in the Inn Valley reached a first climax during that period. In the Late Bronze Age, copper was produced at an almost industrial level.

2013

Der Anschnitt. Beiheft 42, 2019

Since the 1990s, archaeological investigations of prehistoric copper mines have been conducted in the famous mining district of Schwaz/Brixlegg in the Lower Inn Valley, North Tyrol (Austria). A large number of sites (mainly from the Late Bronze Age and up to the Early Iron Age) have been investigated so far with the aim to record and to analyse this extraordinary prehistoric mining landscape. A focal point of research is the reconstruction of the process chain connected to the prehistoric copper production comprising ore mining, beneficiation, and smelting processes. This paper discusses the final step of metal production, the smelting of copper ores. Whereas dozens of prehistoric mines and several sites with traces of mechanical ore treatment have been examined in the last years, only two smelting sites from the period under consideration are known so far. One of these sites, the smelting site Rotholz (municipality of Buch in Tyrol), could be prospected by geophysical methods (geomagnetic) and partly excavated during several campaigns in 2010 and 2015-2017. A detailed documentation of the archaeological remains could be performed in the frame of the DACH-project “Prehistoric copper production in the eastern and central Alps - technical, social and economic dynamics in space and time” (supported by the Austrian Science Fund FWF, the German research foundation DFG and the Swiss National Research Foundation SNF, 2015-2018). The Rotholz smelting site dates into the 12th/11th cent. BC (Late Bronze Age, Urnfield culture, dated by 14C-analysis). The basic raw material used for the local copper production were fahlores which occur in considerable quantities in the Devonian dolomitic hostrock (Schwazer Dolomit). As a result of the excavations a multiphase roasting bed, a battery of four furnaces, a slag heap (crushed slag, slag sand) and many other informative structures could be uncovered and documented. The findings (ceramic, slags, ores, stone tools, animal bones,…) have been furnished to archaeological and archaeometrical analysis.

Der Anschnitt. Beiheft 42, 2019

Within the framework of the international DACH-project “Prehistoric copper production in the eastern and central Alps – technical, social and economic dynamics in space and time” (funded by the Austrian Science Fund FWF, I-1670-G19, the DFG and SNF, 2015 - 2018) traces of Late Bronze Age to Early Iron Age mining activities were systematically prospected and investigated in the fahlore mining district Schwaz-Brixlegg, North-Tyrol, Austria. The aim was to reconstruct the production chain for copper from fahlore and to demonstrate the spatial and chronological development of the prehistoric mining activities in this district. Archaeological excavations were carried out at different places below and above ground comprising a series of fire-set mines, areas with surface depressions (german: “Pingenfelder”) and one smelting site. Besides the uncovering, documentation and interpretation of prehistoric structures and findings it was essential to obtain organic materials like wood, charcoal and animal bones for radiocarbon dating and – in the ideal case – timber and/or charcoal for dendrochronological analyses. These investigations could be realised at different spots distributed alongside the mining district of Schwaz-Brixlegg. Parallel to the excavations relevant sectors of the mines were mapped, mine plans were drawn and 3D-models were generated. In addition to the archaeological fieldwork, ore samples from the mining district were systematically collected for mineralogical and geochemical analyses with the aim to characterise the mineral assemblages for subsequent provenience studies. This paper reports on the mining sites investigated within the DACH-project as well as on first results from archaeometric analyses.

Archaeometry 47, 2 (2005): 293 - 315, 2005

In recent years archaeological finds and scientific analyses have provided increasing evidence for a very early beginning of copper production in the rich mining area of the Tyrolean Alps. The earliest findings derive from an excavation of a multi-phase settlement on the Mariahilfbergl in Brixlegg, which revealed evidence that a small amount of fahlores, probably of local provenance, was at least heated if not even smelted there in the Late Neolithic Münchshöfen culture (the second half of the fifth millennium BC ). However, most copper finds of this horizon consist of low-impurity copper that most probably derives from Majdanpek in Serbia. This long-distance relationship is corroborated by typological features that link some aspects of the Münchshöfen culture with the Carpathian basin. Thus it is not yet clear if, at Brixlegg, actual copper production took place or, rather, an experimental treatment of the local ores. The typical fahlore composition, with arsenic and antimony in the per cent and silver and bismuth in the per mille ranges, appears in quantity only in the Early Bronze Age. Many thousands of Ösenringe are known from many central European Early Bronze Age sites, with a chemical composition typical of fahlores. At Buchberg near Brixlegg, a fortified settlement with slags from fahlore smelting proves that the local ores were indeed exploited. The lead isotope ratios of Ösenringe from the Gammersham hoard in Bavaria, which consist of fahlore copper, confirm this and suggest that copper mining and production in the Inn Valley reached a first climax during that period. In the Late Bronze Age, copper was produced at an almost industrial level.

Der Anschnitt, Beihefte, 2019

Due to numerous Bronze Age traces of mining and metallurgy, the southern Leuken Valley from the Pass Thurn over Jochberg and Aurach to Kitzbühel is one of the most important prehistoric mining landscapes of the Alps. The abundance of sites with archaeological evidence of mining shows that this area was a supra regionally important production area for copper more than three thousand years ago. Essentially, this central mining area has significantly influenced the technological and economic development of Central Europe, the Alpine landscape and the society of the Bronze Age.

The rich copper ore deposits in the eastern Alps have long been considered as important sources for copper in prehistoric central Europe. However, the role that each deposit played is not clear. To evaluate the amount of prehistoric copper produced from the various mining regions, we attempted to link prehistoric metal artefacts with copper ores based on the geochemical characteristics of the ore deposits that were exploited in ancient times. Alongside the usage of ores as shown by the finished products, the production aspects, the quantity and variation over time must also be considered. Recent archaeological investigation has allowed these datasets to be combined in order to show the importance of one of the largest Bronze Age mining fields in Europe. More than 120 ore samples from the well-known mining regions of Mitterberg, Viehhofen, and Kitzbühel were analysed for lead isotope ratios and trace element concentrations. These results were combined with analytical data generated by previous archaeometallurgical projects in order to compile a substantial database for comparative studies. In the Early Bronze Age, most metal artefacts were made of copper or bronze with fahlore impurity patterns, and most examples from this period match the fahlore deposits in Schwaz and Brixlegg. At the end of the Early Bronze Age, a new variety of copper with low concentrations of impurities appeared. The impurity patterns of these examples match the ores from the Mitterberg region. Later, in the Middle Bronze Age, this variety of copper almost completely replaced the fahlore copper. In the Late Bronze Age, the exploitation of the ores changed again and copper with a fahlore signature reappeared. The reason for the renewed copper production from fahlores might have been a decline of the chalcopyrite mines. But it was more likely due to the fact that the rising demand for copper could no longer be met by the chalcopyrite mines alone. The examples from the Early Iron Age show no fundamental changes in metal composition. The copper metallurgy in the Early Iron Age is based on the traditions of the Late Bronze Age.

Conference Series, Innsbruck University Press 2013: 27-32 , 2013

Journal of Archaeological Science, 2015

A number of slags of all known sites in the Italian Eastern Alps showing occurrences of copper smelting activities in the Copper Age have been characterized by lead isotope analysis. All the investigated smelting slags from Trentino (Romagnano Loc, La Vela, Gaban, Acquaviva di Besenello, Montesei di Serso) and Alto Adige/Sud Tyrol (Millan, Gudon, Bressanone Circonvallazione Ovest) have been recently characterized by thorough mineralogical, petrographical and chemical analysis and demonstrated to be the product of copper smelting activities of chalcopyrite-based mineral charges, with an immature technological extraction process referred as the "Chalcolithic" smelting process. Revision of the available radiocarbon dates show that the metallurgical activities pertaining to the analysed slags can be attributed to the third millennium BC. The lead isotope analysis indicates clearly that the mineral charge use for the smelting process was extracted from nearby mineral deposits. The detailed analysis of the spatial distribution of ores and slags allows for the first time to define the local organization of the metallurgical operations.