Cullinan turns 100

In November 2003, De Beers announced that its flagship Premier mine in South Africa would be renamed the Cullinan diamond mine in celebration of the mine’s centenary. The mine once yielded the Cullinan diamond, the largest pure rough diamond ever discovered.

The village of Cullinan, 30 km east of Pretoria, had its beginnings in 1903 when it was named after the pioneer and entrepreneur Sir Thomas Cullinan. It later came to the fore again in 1905, when the Cullinan diamond was discovered. The diamond went on to be globally recognized as a gem of the British Crown Jewels.

The diamond measured a whopping 3,106 carats and was discovered in 1905 by Frederick Wells, a mine superintendent. As the story goes, Wells was walking through the mine at the end of the day when he happened to glance up and notice a large mass in one side of the mine wall. Thinking it was a big piece of glass embedded by a practical joker, he examined what turned out to be a huge diamond. Wells received US$10,000 for his find, and the diamond was named “Cullinan,” after the mine’s proprietor.

The Cullinan was sold to the Transvaal government for US$800,000 and later presented to King Edward VII on his 66th birthday on Nov. 9, 1907. The gift was a gesture of goodwill by the people of Transvaal to the British king for granting the colony responsible government after the end of the Boer War in 1903 (in 1910 Transvaal became part of the Union of South Africa). The Cullinan diamond was insured for $1.2 million when it was sent to England, by mail (after a well-publicized shipping scheme was orchestrated in an effort to throw off would-be thieves).

The stone was sent to the Asscher Brothers in Amsterdam for cutting. They had successfully cut the 995.2-carat Excelsior, previously the largest pure diamond discovered, which was found in Jagersfontein in 1893. The huge uncut stone was studied for months. Then on Feb. 10, 1908, Asscher struck the steel cleaver’s blade to make the first cut. The blade broke while the diamond remained intact.

On the second attempt, it split exactly as planned. It was reported that Asscher had fainted after the second cut. Further cuts produced three principal parts, and these in turn were cut into nine major gems, 96 smaller “brilliants” and 9.5 carats of unpolished pieces. The Cullinan I was the largest gem produced from the rough stone; a pear-shaped stone of 530.2 carats, it is the world’s largest cut diamond.

The Cullinan I, also known as the Star of Africa, is now in the head of the royal scepter in the British crown jewels. The second-largest cut diamond, the Cullinan II, is a cushion-shaped stone weighing 317.4 carats and is set in the British imperial state crown. The Cullinan III is a pear-shaped diamond weighing 94.4 carats and is in the finial of Queen Mary’s Crown and can be worn with the Cullinan IV as a pendant-brooch.

The Cullinan IV, a 63.6-carat cushion shape, was originally set in the band of Queen Mary’s crown. The Cullinan V is a triangular-pear cut weighing 18.8 carats and was originally mounted in a brooch for Queen Mary, to be worn alternately in the circlet of her crown as a replacement for the 109-carat Koh-i-Noor.

Some diamond experts believe that the original Cullinan diamond was only a fragment, and that another piece, possibly as large or even larger, either still exists and awaits discovery or was crushed in the mining process. The prospect of finding another portion of the Cullinan has added enthusiasm to the activities of numerous miners and prospectors.

— The preceding is from an information bulletin published by Johannesburg-based De Beers.