Updated: Jul 21
#27 Science in History
26 January 1905
On this day in 1905, a diamond of exceptional size and quality was discovered in the Transvaal, South Africa.
The Cullinan Diamond, also known as the "Great Star of Africa," is part of the largest gem-quality diamond ever found. It was discovered at the Premier No. 2 mine in Pretoria, and was named after the mine's owner, Thomas Cullinan. At the time of its discovery, the Cullinan Diamond weighed an astounding 3,106.75 carats. The diamond was cut into several smaller stones, the largest of which is the 530.2-carat Great Star of Africa, which is currently set in the British Crown Jewels.
After its discovery, the diamond was presented to King Edward VII as a gift from the people of South Africa. The king tasked Joseph Asscher, a famous diamond cutter from Amsterdam, with cutting the diamond. Asscher's task was not an easy one, as the diamond was so large and had such a unique shape. Asscher decided to cut the diamond into nine large stones (Cullinan I to IX) and 96 smaller ones. Cullinan I was set in the 'Sovereign's Sceptre with Cross' although it had also been adapted to be worn as a pendant or brooch.
The quality of the Cullinan Diamond is exceptional. It is a type IIa diamond, extremely rare with very little nitrogen impurities. Type IIa diamonds are considered to be the purest and most valuable diamonds in the world.
The Cullinan Diamond is a symbol of the power and wealth of the British Empire, and it has played a significant role in the history of the British monarchy. It is a truly remarkable gemstone that continues to fascinate people to this day.