Eight glass tiles from Saint-Sauveur in Burgundy, which are considered to be of early medieval date, were investigated. These tiles, which are in a good state of preservation, are 10 centimeters square and nearly two centimeters thick. They are made of dark glass with red and white glass inlays. These glass tiles have often been compared with those from the early medieval monastery of Corvey in Germany. However, because they lack an archaeological context, their date is uncertain. PIXE-PIGE and LA-ICP-MS analyses revealed a wood-ash glass composition, close to that of High Lime Low Alkali (HLLA) glass dating from the 14th century and later. The authors’ trace analyses confirm the more recent dating because the elements associated with cobalt reveal sources used only from the 16th century.