Technological investigation on ceramic bodies of 19th century French white earthenware from the Bordeaux region

In this paper, we focus on the industrial production of white earthenware in the Bordeaux area (France) in the 19th century. Our main objective is to assess the evolution of production technology. A multi-analytical approach was used to investigate bodies of 150 fragments found in archaeological context. The microstructural, chemical and mineralogical characterization was performed using a combination of Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (SEM-EDS), Proton Induced X-Ray Emission (PIXE) and X-Ray Diffraction (XRD). The results showed that the ceramic bodies were produced by mixing high-Al clays, calcined flint and possibly feldspar. Moreover, the combined use of calcined flint, kaolinite clay and sometimes Co-rich colorant for the preparation of the ceramic bodies highlighted the importance of the whiteness aspect of bodies. Furthermore, the treatment of the compositional data using multivariate statistical analysis revealed different groups of production corresponding to the different chronological periods of production at Bordeaux throughout the 19th century.