The Flame Lily brooch is in the simplified form of such a flower, the national flower of Rhodesia, now Zimbabwe.
It was presented to Princess Elizabeth during a tour of the country in 1947, the year before she married, for her 21st birthday. It was a birthday present from 42,000 children in Southern Rhodesia, with each child having donated some money to the cause. With this money, a 301 diamond and platinum brooch was created for the young Royal.
This was the piece the new Queen wore back to the UK, following her father’s death in 1952. It stood out sharply on the black mourning outfit Elizabeth wore. The Flame Lily brooch is, essentially, the first brooch of Queen Elizabeth II.
Princess Margaret and Queen Elizabeth, The Queen Mother, also received brooches in this form, says FHMJV; The Queen inherited her mother’s in 2002, and we are not too sure if she has worn her mother’s as it seems they are almost identical.