CIRCULATION OF IRON PRODUCTS IN THE IRON-AGE OF EASTERN FRANCE AND SOUTHERN GERMANY: MULTIDISCIPLINARY AND METHODOLOGICAL APPROACHES TOWARDS THE PROVENANCE OF ANCIENT IRON – CIPIA

About 450 samples of ore and slag were taken on archaeological sites in order to determine the chemical and isotopic signature of potential producing areas. An inter-comparison between a statistical multivariate approach on the chemical data and the measured osmium isotopic ratios of the different potential producing areas demonstrates the perfect complementarity of the two approaches: the rare areas that could not be distinguished by one of the two methods were separated by the other one. The chemical signature of artefacts and producing areas were then compared for the different periods. Complete metallographic analyses of the artefacts allowed us to determine the nature and the quality of the ancient metals. Moreover, for the first time on such artefacts, radiocarbon dating was also performed.

Semi products and chariot tires from the Hallstatt period are imported, as other prestige goods from this period. Only artefacts linked to daily life sites and uses are produced locally. The trade networks are the same on each part of the Rhin river, but it exist two parallel networks: the first dedicated to prestige artefacts, the second to daily life artefacts and metal. For the La Tène period, chariot tires found in graves are from more homogenous provenance groups revealing more local and tightened trade networks.

The methodological development in the frame of CIPIA allows us now to go deeper into the archaeological questioning for the next future, by widening the studied area and the chronological period. This will give a better insight in the socio-economical organisation and the evolution of trade during iron age. It is now of primary importance to complete the chemical database of the production areas, on the one hand by increasing the number of analysed sample for the already studied areas, on the other hand by integrating new areas as Bourgogne, Franche-Comté, Sarthe, Eure and Aisne in France, Markgräflerland, Siegerland, Pfalz einn Germany, and Condroz and Eifel in Belgium. It will also be of primary importance to have a look on the areas corresponding to the Mediterranean world as north Italy. In a complementary way, more artefact of the daily life must be analysed, to try to get more information on the specific trade network corresponding to that kind of artefact.

The project delivered 7 papers in international journals with reviewing committee, 23 book chapters, 10 communications in conferences and 7 papers in the mainstream press.

During Iron Ages, the Central and North-West Europe is not a uniform area, many variants emerge and motor centres appear and are replaced by others. These changes are mainly interpreted in terms of trade relations and influence with the Mediterranean world economy. Iron is routinely interpreted as taking an important role in every phase of great upheaval, without having however sufficient archaeological data both in terms of production or trade of ferrous products. The first Iron Age (800-500BC) in Europe is characterised by an aristocracy of very high rank with chariot burials using more and more prestige goods and Mediterranean imports. In the interpretative models, iron is considered driving social hierarchy processes and geostrategic changes in post Bronze Age societies.
Contrary to what has been already proposed, there is still no archaeological evidence that may help linking the emergence of first centralized societies to any iron ore exploitation. The hypothetical link between development of social complexity and iron production emerge actually from a convergence between the presence of historical ore mining and the appearance of burials with Mediterranean imports in the same area.
More lately, from the 5th century the group Aisne-Marne and the Hunsrück-Eifel-culture, is substituting more in the north the former north-Alpine complex. The disruption of trade routes moves closer centres of political and economic power to early iron production sites. However, it is not possible to formally link the emergence of these new centres with iron production. However, no precise data are available on the trade of iron products in short, medium or long distance.
The objective of this program is twofold. It has a methodological orientation in Archaeometry and discusses anthropological and historical issues related to proto-historical periods. The first objective is to exploit, to confront and develop in a complementary way both archaeometric methods for determining the origins of iron products. Indeed, recent methodological development that occurred both in German and French archaeometry laboratories allows now to envisage provenance studies for ferrous and steel archaeological artifacts. This is a real breakthrough for the issues related to Iron Age societies. The second objective is, by applying these methods, to address the two chronological periods of the Iron ages evocated previously and bring a renewed vision of trade relations and of the role of iron in each of the major changes occurring in these periods. For this, we address a specific set of archaeological material on which will be applied innovative methods for determining the origins developed in France and Germany.
The archaeometric methods developed by the two teams are based on the determination of trace element chemical and isotopic (Osmium) signature of production area. Thus in a first step, this signature will be followed in ore, archaeological slag and other wastes of the operating chains found on the sites of potential production areas linked to the issue; i.e. Lorraine, Baden Wuerttemberg, Sénonais, Pays de Bray, West Bavaria. In a second step, we will analyze the chemical signature of two types of objects characteristics of these periods: bipyramidal ingots preferentially distributed in the geographical area of the northern Alps complex and tires of chariot burials representatives of ostentatious funeral deposit zones.