And while we are on the subject of tiaras, here is Nada Milford Haven's ruby and diamond tiara, by Bolin....
According to Geoffrey Munn:
'A gold tiara in kokoshnik form, set with faceted and cabochon rubies and diamonds in the form of stars and crescents, fleurs-de-lys, trefoils and a central radiant heart. Several of the motifs can be detached and worn as brooches. Made by Bolin, for the Grand Duke Michael Michaelovitch, grandson of Tsar Nicholas I, for his bride Sophie de Merenberg, Countess Torby. It passed to his daughter, Countess Nadejda of Torby, who married Prince George of Battenberg (later the second Marquess of Milford Haven).
I think that the tiara has subsequently been sold and returned to Russia?