The Cullinan Diamond
The largest gem diamond ever found travels by post.
On 26 January 1905 a 3,106-carat diamond is found at the Premier mine in Cullinan, South Africa. It reached Britain in a plain box by registered post while a decoy sailed under guard, and Asscher of Amsterdam cut it into stones that sit in the British Crown Jewels, including the 530.2-carat Great Star of Africa.
Open in interactive timeline →Key Numbers
- Rough Weight
- 3,106 carats
- Found
- 26 Jan 1905
- Cullinan I
- 530.2 carats
- Cullinan II
- 317.4 carats
Verified Facts
- The Cullinan was found at the Premier No. 2 mine in Cullinan, South Africa, on 26 January 1905. It weighed about 3,106 carats, and the surface manager Frederick Wells found it about 5.5 metres below ground.
- It was sent to Britain in a plain box by registered post, while a decoy stone travelled on a Royal Navy ship under full security.
- The Transvaal government bought it on 17 October 1907 for £150,000 and presented it to King Edward VII at Sandringham on 9 November 1907.
- Joseph Asscher & Co. of Amsterdam began cutting it on 10 February 1908. Cullinan I (530.2 carats) is in the Sovereign's Sceptre with Cross and Cullinan II (317.4 carats) in the Imperial State Crown.
Myth vs. Reality
Myth:
Reality: The guarded Royal Navy shipment carried a decoy. The real stone went by registered post in a plain box.
Frequently Asked Questions
How big was the Cullinan diamond?
About 3,106 carats rough. It was found at the Premier No. 2 mine in Cullinan, South Africa, on 26 January 1905.
Where is the Cullinan diamond now?
It was cut into several stones. Cullinan I (530.2 carats) is in the Sovereign's Sceptre with Cross and Cullinan II (317.4 carats) in the Imperial State Crown, both part of the British Crown Jewels.
Who cut the Cullinan?
Joseph Asscher & Co. of Amsterdam, starting on 10 February 1908. The work took eight months.
Sources & Further Reading
Cite This Page
AskHistoryAI. “The Cullinan Diamond.” AskHistoryAI — Interactive Timeline of Everything. Updated 2026-10-08. https://askhistoryai.com/event/sv-cullinan-diamond/
Every fact on this page is checked against the published fact ledger and methodology; sources are listed above.