Iron Supply for the Building of Metz Cathedral: New Methodological Development for Provenance Studies and Historical Considerations

This paper develops new reflections regarding the provenance of iron artefacts, by defining the trade networks that might have supplied the building yard of the Metz city belfry at the end of the 15th century. Regional field surveys were carried out in Lorraine in order to constitute a chemical repository, including ironmaking zones considered as the most probable metal providers. The chemical characterization—both major and trace elements—of slag inclusions entrapped in the metallic matrix of iron reinforcements was performed in order to compare their chemical signature to the reference set. A statistical approach based on the combined use of descriptive multivariate analyses was developed to infer the origin of the metal supplied to the building yard. As the multiplicity of potential metal providers was assessed from former studies, the results obtained underline the place taken by local workshops in the supply strategy developed by the builders. This study thus provides crucial information supporting a discussion about the scale and the organization of such networks at the end of the Middle Ages.