Queen Mary’s Crown was made in 1911 by Garrad’s for the coronation of King George V and his wife, Queen Mary. The design was inspired by Queen Alexandra’s Crown, which had been created in 1902. The famous Koh-i-Noor diamond featured in both crowns, which is now in Queen Elizabeth The Queen Mother’s Crown. It can be worn without the arches, making it a regal circlet. Queen Mary wrote this version for the coronation of her son, King George VI, in 1937.
The Crown has a silver frame lined with gold and set with 2,200 diamonds. When Queen Mary wore it for her coronation, it contained three large diamonds, the Koh-i-Noor and Cullinan III and IV. These were replaced with quartz crystal replicas after the coronation.1
Before Queen Adelaide, Queen Caroline (of Brunswick) was not allowed to attend her husband’s coronation. Her predecessors, Queen Charlotte (of Mecklenburg-Strelitz) and Queen Caroline (of Ansbach), were crowned with Queen Mary of Modena’s Crown. This was also used by the Queens regnant, Queen Anne and Queen Mary II. However, the jewels were reset for the coronations of Queen Mary II, Queen Anne and Queen Caroline.
All of these crowns are (usually) on display at the Tower of London.