The ancient stone that sparkles on a crown filled with history

On Wednesday afternoon, King Charles read his speech at the State Opening of Parliament. He was wearing one of the most important symbols of monarchy for it, the Imperial State Crown.

The Imperial State Crown is worn by the British monarch when they leave Westminster Abbey at the end of their coronation. They also wear the Imperial State Crown for the State Opening of Parliament. (Queen Elizabeth II chose to not wear it at the end of her reign due to its heavy weight.)

The crown features several historic gems. The Cullinan II diamond is mounted on the front of the crown- it is a 317 carat diamond also known as the Second Star of Africa. The Cullinan Diamond is the largest rough quality diamond found and was presented to King Edward VII who had it cut into several different pieces.

The Stuart Sapphire is 104 carats and is mounted on the back of the Imperial State Crown. King James II took the sapphire with him when he fled following the Glorious Revolution in 1688; King George III was able to buy the gem back in 1807. When Queen Victoria wore the Imperial State Crown, the Stuart Sapphire was mounted on the front.

The Black Prince’s Ruby is mounted on the front cross and is actually a 170 carat spinel. Its provenance dates back to 1367 when it was recorded to belong to Prince Edward of Woodstock.

St. Edward’s Sapphire is mounted at the centre of the top cross of the crown. It is believed the be the oldest gemstone in the British royal collection; historians believed that St Edward the Confessor wore it in his ring for his 1043 coronation at Winchester Cathedral.