I'm sure many of you know this already, but I didn't, so I figured I'd share this....
I was meeting with a custom knife maker yesterday (to chat about knives) and the topic turned to the material used for grips. He does a lot of ivory (real ivory), warthog tusk, horn and giraffe bone. He said that all of these shrink with time and noticeably so, even in a pretty short while.
I had always thought that once these materials had "dried out" they would be very stable, but it seems not. He showed me a knife made late last year with ivory grip slabs and it was noticeable that the material had "shrunk" if you felt around the tang area.
I'm almsot cured of my desire to put these materials on my revolvers!