I think that the other thing to add is that the scale of the crown may not work with the Queen's hairstyle.
As CountessKate points out, the last person to wear the crown was Alexandra (with great style it must be added) and it worked with her hairstyle, sitting atop her coiffure, which had largely remained the same style-wise since the 1880's.
In terms of the Queen choosing to wear something lighter as opposed to the Imperial State Crown, I'm not sure what the protocol would be.....thinking of the State Opening or Parliament etc?
Queen Mary of course had a new tiara made for her later years, perhaps finding some of her other pieces too heavy? In the book there is a description of this jewel, and the jewels that were used to make it. It would appear that she used the pendant Cambridge emeralds as spikes on this new lighter tiara (obviously also using them on the Vladimir tiara).
The book also gives new and interesting information about the Cambridge emeralds. It also clears up the confusion about the fringe tiaras as well as giving interesting new information about how Queen Mary had new pieces created quite economically from existing jewellery in her collection. The book only hints at what she may have acquired in the 20's when it appears that she really cashed in on the royal jewellery that was appearing for sale. There are also some great pieces that belonged to Queen May which have languished unworn in the collection of the late Queen Mother, such as her diamond 'Love Trophy' collar, an exquisite jewel of wondrous workmanship, which has not been seen for years and years. I think that many will find the information about the Greville collection quite interesting as well. The photography is excellent and totally justifies the rather high purchase price of the book.
