I have an old instrument (40 years or so) in which a large rectangular mother of pearl inlay has fallen off. What is the best way to set it back in (i.e., what glue, should it be replaced instead, etc.)

Thank you.

I have an old instrument (40 years or so) in which a large rectangular mother of pearl inlay has fallen off. What is the best way to set it back in (i.e., what glue, should it be replaced instead, etc.)

Thank you.

The original piece was probably installed with hide glue. As a permanent repair, I believe that it is OK to replace it with superglue. I would use a gel type to help fill the voids left over from the old glue.