What is the Largest Diamond in the World?

Known as the “Star of Africa,” or the Cullinan Diamond, the largest diamond in the world is a whopping 3,106 carats for a weight of 1.3 pounds. The diamond was originally found in 1905 in the Premier Mine in Pretoria, South Africa by Thomas Evan Powell. As simply an employee, Powell gave the diamond to Frederick Wells, the mine’s supervisor, in order to gain better knowledge of what to do with it. The process of uncovering this diamond was not special in any way; Powell found it during a routine inspection eighteen feet below. Even more impressive, the diamond mine is large, but it is by no means the largest diamond mine in the world. In fact, it is not even on the list of the top ten. With this being said, the press grew very intrigued because of the diamond’s size and the smallness of the mine. The diamond, therefore, became an international sensation.

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Sir William Crookes performed his analysis of the diamond and pointed out the black spot in the middle of the stone, despite its remarkable clarity. While black spots are not uncommon in diamonds, Crookes ascertained that since the colors around the black spot were incredibly vivid, the black spot was a sign of internal strain. Additionally, one side of the diamond was nearly perfectly smooth. Crookes took this to mean that the diamond was actually much larger at one point in time, but it had since been broken up by natural forces, leaving a smooth edge. While the Cullinan Diamond is the largest diamond discovered as of yet, Crookes came to the conclusion that what was found was less than half of the entire diamond.

The name, Cullinan, comes from the mine’s owner; Wells decided to present his finding of the large diamond to Sir Thomas Cullinan on January 25th, the same day in which the diamond was found, and therefore, he christened the diamond after the mine’s owner. Immediately, Cullinan wanted to document the find and had a picture of the largest diamond in the world taken while he sat right beside it. Instead of keeping this diamond to himself, Cullinan sold the diamond to the Transvaal provincial government, who later gave the diamond away to King Edward VII as a present for his 66th birthday. The King originally did not want to accept a gift of such monumental importance and value, but it was Winston Churchill who finally convinced him to accept the diamond. Churchill did not get away empty-handed though; he received a replica of the diamond which he showed off to many guests and friends with a huge smile on his face.

From the beginning, King Edward VII was aware of the immense value of this special discovery. Therefore, in the process of sending the stone to England, he requested a decoy diamond be sent before the actual diamond in order to prevent thieves from stealing it.


Gemologist Marcel Tolkowsky, who was also a Mathematician, died at age 92 leaving his legacy of a shining diamond. He has family history that is deeply embedded in the cutting of diamonds. His nephew, Gabi Tolkowsky, invented what came to be known as the flower cut of diamonds and now works as a consultant for one of the largest diamond manufacturers in the world, De Beers. He has a cousin, Lazare Kaplan, who is the owner of a manufacturing and distributing diamond business in NY City. Marcel was made famous when he created a mathematical formula for the greatest brilliance in diamonds and was responsible for inventing the round brilliant cut diamond. He came up with the theory that for a diamond to have maximum reflected light and increased brilliance, it needs to have 58 facets. His diamond was subsequently called the “Tolkowsky Brilliant,” or the “American Ideal Cut” diamond.

After receiving the diamond, the king sent it to one of the most prestigious diamond cutters in the world at the time, Joseph Asscher, in Amsterdam. Although the cutter was extremely talented and experienced, the Cullinan diamond was no easy feat for him. Instead, he spent six months studying all aspects of the diamond before making a single cut. With Asscher’s first attempt, the blade he used broke. Therefore, during his second attempt at cutting, Asscher was so nervous that after the diamond was cut as planned, he fainted. However, there is little evidence that this story actually happened, and his nephew has said that Asscher would never faint over a diamond. Others said it was much more likely that the cutter wouldl have celebrated with a bottle of champagne. Either way, Asscher would have been relieved, to say the least, to have cut a diamond of such gargantuan proportion so perfectly.

The Cullinan diamond is not fully intact; instead, it has since been cut into nine large stones and nearly 100 smaller ones. This cutting, however, does not diminish the value, as all of the stones are valued at millions of dollars together. “Star of Africa I,” or “Cullinan I,” is the largest stone to come of the original Cullinan diamond. Estimated at 530 carats, the diamond is the largest cut colorless diamond in the world. Additionally, it was the largest polished diamond of any color until the Golden Jubilee Diamond was discovered in 1985 in the Premier Mine, the same location in which the Cullinan diamond was found. Today, the diamond is located in the Tower of London in the British Sovereign’s Royal Scepter. The diamond is not alone there, as the Cullinan II, along with some of the other smaller cuts of the original Cullinan diamond, is also located in the Tower of London as part of the Crown Jewels. As far as the other cuts from the Cullinan diamond are concerned, Queen Elizabeth II holds a private collection inherited from her grandmother, Queen Mary, with seven of the major cuts and 96 minor cuts.

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