Top 10 largest diamonds in the world
From the world of glamour to royal palaces, diamonds have been a symbol of wealth and prestige for centuries. These precious stones come in all shapes and sizes, each one unique in its own way. Miners occasionally make exceptional discoveries, turning massive roughs into legendary gems. What is the largest diamond in the world? Here is the top 10 of the largest stones ever discovered.
Article updated on July 30, 2025
Table of Contents
- The Sergio Diamond
- The Cullinan Diamond
- Graff Lesedi La Rona
- The Excelsior Diamond
- Star of Sierra Leone
- The Incomparable
- The Constellation Diamond
- The Koh-i-Noor
- The Millennium Star
- The Woyie River Diamond
The Sergio Diamond: The Largest Black Diamond in History
The Sergio Diamond tops the list of the 10 largest black diamonds ever discovered. This black diamond, weighing 3,167 carats, was found in 1895 in Bahia, Brazil. "Carbonados" are very rare, though not highly valuable. They are the hardest variant of diamonds and often resemble carbon in their natural form.
Some experts believe this stone came from space, specifically from a fragment of a supernova that landed on Earth 2.3 billion years ago. The Sergio was cut into numerous small diamonds of 3 to 6 carats, which were used for industrial purposes. This is why it is often omitted from the top 10 largest diamonds in the world.
The Cullinan Diamond
The largest gem-quality diamond ever found is the Cullinan. It weighed 3,106 carats (1.37 kg). Discovered in 1905 near Pretoria, South Africa, in the famous Premier Mine, Sir Thomas Cullinan gifted this magnificent stone to King Edward VII. After cutting and polishing, 9 major stones (including the Cullinan I at 530.4 carats) and 96 brilliant-cut stones were produced. These diamonds are still primarily part of the British Crown Jewels.
But how do you recognize a real diamond? Click the link above to find out.
The Graff Lesedi La Rona
This 1,109-carat rough diamond was discovered in 2015 by Lucara Diamond in the Karowe Mine in Botswana. The Lesedi La Rona, the size of a tennis ball, was too large to be extracted with the mine's equipment. A custom-built scanner and new imaging software were created. After studying the rough for months, Graff cut a square emerald-cut diamond weighing 302.37 carats with exceptional clarity (see photo below and our guide to the 4Cs of diamonds). It is the largest square emerald-cut diamond in the world.
The rough also produced 66 smaller diamonds. The 302.37-carat emerald-cut diamond was named Graff Lesedi La Rona.
The Excelsior Diamond
The Excelsior was the largest diamond in the world until the discovery of the Cullinan. The stone was found in 1893 by a miner in the Jagersfontein Mine in South Africa. Due to its size and the quality of the diamond, it was difficult to find a buyer.
Finally, in 1904, the 995.2-carat diamond was sent to I. J. Asscher, a renowned diamond cutter in Amsterdam. He cut it into 10 stones. The largest gem is a pear-shaped diamond weighing 69.69 carats.
The Star of Sierra Leone
The number 5 in the largest diamonds in the world ranking was found in 1972 in the Diminco Mine in Sierra Leone. The diamond was initially purchased for around $2.5 million by the jeweler Harry Winston, who cut the 969-carat rough into an emerald cut. When an internal flaw was noticed, the diamond was recut into 17 smaller stones, the largest being a pear-shaped diamond weighing 53.96 carats.
The Incomparable
One of the largest diamonds in the world, the Incomparable, was discovered in 1989 by a young girl playing in the Democratic Republic of Congo. It took experts 4 years to analyze and finally cut the 890-carat diamond. It was decided to cut a smaller, flawless diamond rather than retain a larger, lower-quality stone. The resulting 407.78-carat diamond, the Fancy Deep Brownish Yellow, is free of internal flaws.
The Constellation Diamond
Extracted in 2015 from the Karowe Mine in Botswana, the Constellation Diamond weighed 813 carats. It was originally owned by Lucara Diamond Corp. After several transactions, the diamond was acquired by De Beers, who then resold it to Zale Corporation.
At a highly publicized sale in 2016, the diamond was purchased by the Dubai-based company Nemesis International DMCC for a record $63.1 million.
The Koh-i-Noor
The Koh-i-Noor is one of the most legendary diamonds. It also ranks among the most expensive diamonds in the world. Its history dates back to at least the 13th century. It was discovered in the Kollur Mine in India. The 793-carat rough diamond was owned by the ruling dynasty, Sikh, Mughal, and Persian leaders.
In 1849, Queen Victoria became the owner of the Koh-i-Noor. In 1852, Prince Albert demanded that the diamond be cut, resulting in an oval-cut diamond of 186 carats. The Koh-i-Noor remains the property of the British Crown today.
The Millennium Star
Originally extracted from the Mbuji-Mayi Mine in the Democratic Republic of Congo in 1990, the Millennium Star weighed 777 carats in its rough form. Purchased by De Beers, the Millennium Star was cut by the Steinmetz Group to produce a D-color (flawless) pear-shaped diamond weighing 203.04 carats.
The cutting of the Millennium Star took 3 years. In addition to producing the largest pear-shaped diamond, a vivid blue fancy heart-shaped diamond weighing 27.64 carats and 11 blue diamonds totaling 118 carats were also created from the rough.
The Woyie River Diamond
Here is the last entry in this top 10 of the largest diamonds in the world, the Woyie River. Extracted in 1945, this 777-carat diamond was named after the river where it was found, the Woyie. At the time, the Woyie River diamond was the largest alluvial diamond ever discovered.
The rough was then transported to Great Britain. It was exhibited at the British Industries Fair in 1949. The diamond was eventually cut into 30 stones. The largest diamond produced is the Victory Diamond, named in reference to the Allied victory during World War II.
FAQ: Largest Diamond in the World
545.65 carats for the largest cut diamond (Golden Jubilee Diamond), 3,167 carats for the largest rough (the Sergio).
The name of the largest diamond in the world (cut) is the Golden Jubilee Diamond.
The Youkounkoun is a famous diamond name, and the largest in the world… in the film "The Sucker." It does not exist.
