My own mix of Dark Burly, Izmir, 2 lats, and perique in a smooth 1/4 bent Wally Frank Ltd. Algerian Briar Dublin, with vulchanite saddle stem.
When I got this pipe and started to clean it I was much less experienced and almost immediately broke off a piece of the button. D'oh!
It went back together with glue and hasn't been a problem nor is it even visible, at least, not to my tired old eyes. This pipe is right up there with the good ones.