Thanks very much for providing that list, Franck. Interestingly when looking for information on the Dowager Countess of Onslow - who presented the ruby butterfly - I discovered that her grandmother was the Baroness Poltimore for whom Princess Margaret's famous tiara was originally made.
As for the other jewel you mentioned, I think it could possibly be one of the cameo brooches mentioned on the list based on the appearance in the photo below. It is in the bottom right corner of this photo in the black case partially in the shadows.
on January 20, 2012, 10:32 pm, in reply to "