Thanks for the shout-out Beth.
I am still here lurking in the background but have not had much time to devote to the board.

As for this brooch, it is one of those which has been seen occasionally over the years but one for which the provenance is unknown.

HM did wear the brooch in 2006 at a meeting with former Australian Governors General... which might suggest an Australian connection But I am sure if there was one, Beth would have sussed it out by now.

Sorry I could not have been more help