Hello all,  Out here where you can't get anything, we have used the
following with success.

Mix some of the white in a tube that you purchase from the art shop
for use with water colours with PVC wood glue. It should become a
paste.  Then glue it with that. It needs to be clamped in place for
some hours though and the key need to be removed to do a proper job.

The biggest problem with gluing ivories is that anything that is not
white shines through.  Many glues work well but after a while, or even
right after the job is done, the key has a different colour or a dirty
look.  That is because it is not stuck on with white glue.

I have also read in some of Craig Brougher's postings somewhere that
the original way to glue them was animal glue mixed with Plaster of
Paris powder.  That makes a lot of sense to me and I will certainly try
it when I have some more ivories to re-glue.  If that works, it will be
my preferred method.

I have also used 2-component white epoxy for some emergency repairs.
The real trick is that the ivory must be absolutely clean on the side
to be glued.  Any dirt or blackness will show up on the other side once
glued down.

Good luck,

Bernt Damm
Cape Town