Applying archaeomagnetic methods to virtually reconstruct the kiln-loading patterns and manufacturing location: Insights from Tiebas Castle (Spain)

Archaeomagnetism is frequently used for dating baked-clay materials. When the original position of the material is preserved and if the secular variation of the geomagnetic field is well-known in this region, it is possible to date the moment when the baked structure acquired its thermoremanent magnetization (TRM). In this article, the inverse process was applied on a tile production from Tiebas castle (Spain): from the known chronology and direction of the thermoremanent magnetization, the original orientation was virtually reconstructed. The main objective of this innovative application was to determine the exact orientation of each tile in the firing kiln and to infer how tile kilns were loaded during the Middle Ages. The results confirmed that all tiles were placed vertically on one side. These positions were repeated across all rows and tiers. Additionally, this novel approach clarified that the tiles, although crafted by French artisans, were produced locally in Navarra rather than in Champagne. This novel application demonstrates the potential of archaeomagnetism for broader use in reconstructing historical ceramic structures and their contexts.