Changing Origins and Trade Routes of Scottish Window Glass

Window glass used in Scottish medieval ecclesiastic and monastic buildings was not made in Scotland. Instead, all glass was imported but there is limited evidence as to where this window glass was made. In this chapter, archaeological and archival evidence for window glass in the twelfth-fifteenth centuries in Scotland has been re-examined and previous work to chemically characterise glass compositions from these regions is summarised. The largest program of chemical characterization of late medieval window glass yet carried out in Scotland was undertaken to provenance the location of manufacture of the window glass used in a range of buildings. This research has confirmed the supposition that window glass was imported from the continent to Scotland via east coast sea routes. In the thirteenth century, glass was predominantly imported from North-West France/Normandy. By the early fourteenth century, glass was also being made and imported from the Lorraine/Argonne region of France and what is now North-West Germany/Rhineland. The glass from these regions was made using a different recipe with a high lime, low alkali (HLLA) composition. There is no evidence of window glass used in Scotland during this period, having been manufactured in England.