The Cullinan Diamond is the largest rough diamond ever found. It was discovered in the Premier Mine in Cullinan, South Africa in 1905. The Cullinan Diamond weighed 3106.75 carats (621.35 grams) and was named after the mine chairman, Sir Thomas Cullinan.
The Cullinan Diamond was presented to King Edward VII of England on his 66th birthday in 1907. He had the diamond cut into nine large stones and 96 smaller stones. The largest of the nine stones is the Cullinan I (also known as the Great Star of Africa), which is set in the Sovereign's Sceptre with Cross. The Cullinan II (also known as the Second Star of Africa) is set in the Imperial State Crown.
The Cullinan Diamond is on display at the Tower of London in London, England. It is one of the most popular tourist attractions in the world.