March 11, 2025

How Decoys, Diversions Ensured Safe Passage of 3,106-Carat Cullinan Diamond

On January 26, 1905, Captain Frederick Wells was conducting a standard inspection of the Premier Mine in South Africa about 18 feet below the surface when a glint off the wall caught his eye. At first, he thought it was a shard of glass embedded by a practical joker. But, then he pulled out his pocket knife and pried the object from the wall.

What he extracted was the now-famous 3,106-carat Cullinan Diamond, the largest gem-quality rough diamond ever discovered. The Cullinan weighed 621 grams (1.37 pounds) and was 10.1 cm (3.97 inches) long, 6.3 cm (2.5 inches) wide and 5.9 cm (2.3 inches) deep.

Two years later, the mine owners sold the Cullinan for £150,000 to the South African Transvaal Colony government, which intended to present it to King Edward VII on his 66th birthday as a commemorative tribute to five years of peace between the two countries following the Second Boer War.

The challenge of shipping the world’s largest diamond from South Africa to the King of England would provide the first of two examples of how officials used decoys and diversions to ensure its safe passage.

This is how royalasscher.com described the plan: “With the ravenous eyes of the international press watching the diamond’s every move, the colonial government set up a decoy of armed guards and military personnel, intentionally making a grand production of transporting the Cullinan to the British capital.”

Actually, the Cullinan diamond was shipped to London in a plain box via registered post. And the diversionary tactic worked perfectly.

(Interestingly, luxury jeweler Harry Winston would use a similar method to deliver the Hope Diamond from his New York office to the Smithsonian in Washington, DC, a half century later.)

The British King was advised that the Cullinan needed to be cleaved into smaller stones before it could be cut and polished. This was enormously complex and involved significant risk for a stone valued in 1908 at £250,000, more than £38.4 million ($49.4 million) today. The King hired M.J. Levy & Nephews to oversee the operation. At the time, insurance was taken out “against loss, theft and damage of every kind, excepting damage caused by cutting.”

M.J Levy & Nephews arranged for the diamond to be cut and polished by the renowned Asscher Company in Amsterdam, which had successfully cut the previously largest known diamond, the 995.2-carat Excelsior, five years earlier.

And here is where the second decoy operation was put into motion.

For Joseph Asscher to cut the stone, the Cullinan would need to make another perilous journey to the heart of the diamond cutting industry — Amsterdam.

Once again, with much fanfare and public attention, a sealed box supposedly containing the Cullinan was placed on a Royal Navy ship destined for The Netherlands. In this case, the box was empty.

Joseph Asscher’s brother, Abraham, meanwhile boarded a passenger ship heading to the same destination. Stowed away in the deep pocket of his heavy coat lay the uncut diamond that had become the talk of the world.

The mission was a success as Abraham and the Cullinan arrived safely at Tolstraat 127, Amsterdam, the headquarters and cutting factory of Asscher Diamond Company.

After an extensive period of studying the stone, Joseph Asscher started the cutting process by creating an incision in the diamond of approximately 6.5mm deep. It has been reported that Asscher broke his tool when he initially struck the stone. A week later, after developing stronger tools, Asscher successfully cleaved the Cullinan into two principal parts, weighing 1,977 carats and 1,040 carats.

It’s been reported that the failed first attempt was done in front of a gallery of the press and local dignitaries, while the second attempt was accomplished with nobody in the room, except for a Notary Public. Legend has it that Asscher struck the diamond so hard that he fainted after it split.

Over the following months, these diamonds were further polished and cut to create nine principal stones, 96 smaller diamonds and a quantity of polished “ends.”

The largest of the Cullinan gems, the Great Star of Africa (Cullinan I), weighed 530.4 carats and was set atop the Sovereign’s Sceptre. The 317-carat Second Great Star of Africa (Cullinan II) was set in the Imperial State Crown.

And how was Asscher compensated for his work? The master diamond cutter was paid in “chippings,” the small fragments that result from the cutting process. And some of those diamond fragments still live more than 100 years later in the bridal sets of Asscher’s descendants.

Credit: Cullinan replica photo by James St. John, CC BY 2.0, via Wikimedia Commons.