While there are many striking aquamarine tiaras across royal collections, Princess Anne may be able to claim that she has the most unique, the Cartier Aquamarine Pineflower Tiara. 

King George VI commissioned a new tiara from Cartier for his wife, Queen Elizabeth. It is unclear when exactly it was created; dates suggested range from the late 1930s to 1950. 

The unique tiara features several aquamarine pineflowers, as well as rectangular aquamarines mounted on prongs. The platinum base has both square aquamarines and diamonds. Pineflowers are a symbol of enlightenment.

Queen Elizabeth (later the Queen Mother) wore the tiara publicly on two different occasions. In December 1950, she wore it to the Old Vic (newly reopened) for the Royal Gala Performance of William Shakespeare’s Twelfth Night. 

She then wore it in July 1951 to the Royal Opera House in Covent Garden where the Sadler’s Wells Ballet hosted a Gala Performance of Frederick Ashton’s Tiresias. 

The Queen Mother gave the tiara to Princess Anne in 1973 as a present for her wedding to Captain Mark Phillips. She first wore it in 1974 in New Zealand for the Commonwealth Games’ Farewell Banquet. 

In the 1990s, the Princess Royal remodelled the tiara and had the major pineflower removed to create a new brooch. She also used one of the rectangular aquamarines to make a new pendant.