|The Imperial State Crown is one of the Crown Jewels of the United Kingdom and symbolizes the sovereignty of the monarch. It has existed in various forms since the 15th century. The Imperial State Crown made in 1937 for King George VI features 2,868 diamonds, 273 pearls, 17 sapphires, 11 emeralds and 5 rubies.|
The Imperial State Crown is 31.5 cm (12.4 in) tall and weighs 1.06 kg (2.3 lb) The frame is made of gold, silver and platinum. Notable stones are St Edward's Sapphire on the top cross and the Black Prince's Ruby (a large spinel) on the front cross. In 1909, the 104 carat Stuart Sapphire, set in the front of the crown, was moved to the back and replaced by the 317 carat Cullinan II – the second-largest clear cut diamond in the world.
The crown is worn by the monarch on leaving Westminster Abbey at the end of the coronation ceremony. It is also worn at the annual State Opening of Parliament.