I have consulted with several sources in our library, listed in a bibliography on silver stains. Meredith Lillich says that although the technique of silver staining was first introduced to medieval stained glass around 1300, it is mentioned in the 9th century manuscript "Mappae Clavicula", and that the use of silver to make yellow decoration (called lustre) was known in Egypt in the 10th-12th centuries. After 1171, the Egyptian artisans using lustre decoration fled to Syria and Arab Spain. David Whitehouse, Robert Brill, and Bill Gudenrath, all staff members at our museum, have also written about lustre decoration in Egyptian and Islamic glass.
I am attaching a bibliography on the subject, in case you want to do further research. If you have additional questions, please do not hesitate to contact me.
