In Swiss Romande there is a stain glass museum. Maybe they can help you date it.
http://www.musee-du-vitrail.com/
ETA: It is in Romont which is the hub of stain glass making in switzerland.
I've been directed to someone in Fribourg who is a stain glass specialist. Do you want me to send the photos of the window?
http://www.musee-du-vitrail.com/
ETA: It is in Romont which is the hub of stain glass making in switzerland.
I've been directed to someone in Fribourg who is a stain glass specialist. Do you want me to send the photos of the window?