Early medieval stained-glass window from Stavelot (Belgium)

This paper concerns the early medieval window glass from the monastery of Stavelot. The number of fragments, the surface and the quality of conservation are quite exceptional and Stavelot appears as a very important site for the study of ancient glass, especially glass from the early Middle Ages that is still little known. Beside their interest for the history of the site and its comprehension, these glass artifacts give us the possibility to reach the history of stained-glass window and glass fabrication techniques. The archaeological study allows us to quantify and characterize the fragments (shapes, colors, shaping techniques). The analyses in PIXE-PIGE provide the glass composition. Further the coexistence of soda and potash glass in the same archaeological contexts, it points out compositional groups revealing various recipes. Thanks to it, we can also reach coloration process. Finally, the question of glass production on the site is debated.