I have just read (once again) :

The royal jewels by Suzy Menkes Page 53 (Edition 1988, section Majestic Mary)

"The Empress Marie's superb sapphires - two tiaras, a brooch and a pearl choker- were inherited by the Queen. Princess Michael of Kent has a large diamond brooch, the Gloucesters a tiara and Princess Margaret a sapphire"


I asked the question in 2013.

https://members2.boardhost.com/royal-jewels/msg/archive/1387127353.html

At that time, I was not convinced by the answers. Even thought she has made many mistakes Suzy Menkes has revealed some mysteries :

- Queen Alexandra's diamond collet necklace ;
- the double greek key pattern tiara was also described by Menkes.

Franck