This book really is solving a lot of mysteries about the Windsor jewel vault.
It also says the Teck tiara is on loan to Camilla. The question is why haven't we seen it on her?
Also the Surry Tiara was broken up. Some of the stones replaced the pearls on the "Girls" and the rest went to the creation of the Gloucester Palmette Tiara.
Queen Mary's Loop was broken up in favor of the Dehli Durbar (although I heard rumors of that before so it's not that surprising).
To me, the worse is confirmation that the Nizam of Hyderbad tiara has indeed been broken up to create the Burmese Ruby Horror.
On a happier note, we now know that Alexandra's circlet went to Maude and is being worn regularly by Sonja (sans the fleur de lys motifs).