Upper Left to Right: Cullinan I-IV - Attribution: Chris 73 / Wikimedia Commons

This is a collection of the largest and most expensive diamonds mined from different parts of the world. These diamonds made it to the list by virtue of their size and high quality. There might be other recorded diamonds larger in size, but due to the lack of quality, they are not part of this list.

The order of these diamonds is based on the original size of the stone when it was discovered prior to cutting.

Before beginning the list, it is only fair to mention the Koh-i-Noor which is not part of the largest diamonds list but is the most treasured diamond of all times. Koh-I-Noor story and history makes it one of the most treasured and perhaps valuable stones of all times. It was discovered around the 13 ^thcentury in India and has been part of the lives of many historical figures and empires throughout time. In the present time, it is part of the British Crown Jewels. 

Koh-I-Noor - Attribution: Chris 73 / Wikimedia Commons

1.The Cullinan Diamond

The largest and most expensive diamonds are:

1. The Cullinan Diamond

Discovery: The Cullinan diamond was discovered near Pretoria, South Africa in 1905. Before it was cut and polished the original stone weighed 3106.75 carats and was 4.1 inches long.

Famous for : The rough diamond was cut into 105 diamonds, with 9 large and 96 small stones. The largest of the 9 diamonds is known as the Cullinan I or the Star of Africa and weighs 530.4 carats making it the world’s largest cut and polished white diamond. The star of Africa and the rest of the diamonds cut from the original Cullinan belong to the British Crown Jewels.

Value: The Cullinan estimated value is $400 million USD.

Rough Cullinan prior to cutting

2. The Nameless Diamond

Discovery: The origin of the Nameless black diamond or carbonado remains a mystery.

Famous for : This rough diamond was originally 1,000 carats in weight, and cut into a stunning 489.07 carats polished gem. Although scientific studies on the origin of the diamonds point to Brazil or Central Africa as the only possible sources of black diamonds, the origin of the Nameless has not been established, neither is its discoverer or the date of discovery. These circumstances led to the stone being referred to as The Nameless or Anonymous Diamond.

The history of the diamond is as mysterious as its origin. The last known record of the Nameless diamond’s activity in the diamond market was its purchase by a still anonymous buyer in 2001.

Value: It was sold in Dole, France for € 1,829,388.

3. The Excelsior Diamond

Discovery: The Excelsior was discovered in June 30, 1893 in the Jagersfontein Mine located in South Africa.

Famous for : This gem had a bluish-white tone, and weighed 971 carats. Unfortunately, its discovery was not widely publicized in the British newspapers due to the event of the mining company contract expiration and the purchase of the London firms on the same day of the stone’s discovery. The stone was cut into ten gems weighing between 13 to 69 carats each. A single large piece was never produced from the rough stone for unknown reasons. It was cut into small gems of assorted shapes that were bought by different buyers.

Value: The largest stone cut from the Excelsior diamond weighing 69.68 carats was sold in 1996 for $2,646,000. The rest of the smaller stones were used in making fine jewelry such as bracelets and tiaras.

4.Star of Sierra Leone

Discovery: The Star of Sierra Leone was discovered in Diminico mine in Sierra Leone in February 1972.

Famous for: The Star of Sierra Leone is the world’s third largest and best gem in quality, and the largest diamond discovered on an alluvial mine. It is also known for its perfect chemical purity, and the absence of plastic distortions in its crystal. The stone was first cut in an  emerald shape FCUSHweighting 143.2 carats, but had to be re-cut into 17 diamonds that meet the perfect cut scale. The largest stone of the Star of Sierra Leone weights 53.96 carats cut in a flawless, pear shape. Six of the smaller diamonds were made into a famous brooch called the “Star of Sierra Leone” by the jeweler Harry Winston.

Value: In 1972, the initially cut Star of Sierra Leone was sold to Harry Winston for around $2.5 million USD.

5. The Incomparable Diamond

Discovery: The Incomparable was discovered in a pile of rubble in Mbuji Mayi in the Democratic Republic of Congo in the 1980s. The rough stone weighed 890 carats.

Famous for : The extraordinary color of the Incomparable showed varying colors of pale yellow to amber. The biggest cut produced a diamond of 407.48 carats and graded as internally flawless clarity. The Incomparable appeared in an auction in London, and then in New York in 1988. It is the biggest diamond to be offered for sale in the public, but was never sold as the bidding did not reach the seller’s reserved price of $20 million USD.

Value: Estimated at $20 million USD.

6. The Millennium Star

Discovered: Discovered in 1990 in an alluvial deposit in Mbuji-Mayi district, Zaire.

Famous for : The biggest gem cut from the original stone weighs 203.04 carats and is famous for being internally and externally flawless with top color grade. The Millennium is the second largest colorless diamond. Its pear cut was done with the use of lasers, and it took three years to finish.

Together with the other Millennium collection diamonds, it was displayed in London’s Millennium Dome in 2000 where an attempt at stealing the collection was stopped by the police.

Value: It is insured for £100,000,000.

7. The Woyie River Diamond

Discovered: It was discovered in the Woyie River in eastern Sierra Leone in January of 1945.

Famous for: The uncut stone was originally 770 carats, the largest of its kind (alluvial diamond) to be discovered at the time. It was also the third biggest diamond found in Africa, before the Star of Sierra Leone was discovered in 1970. The stone was sent to London to be cut by Briefel and Lemer and was cut into 30 stones. The largest diamond cut from the rough stone is known as the Victory diamond, which is an emerald cut and weighs 31.25 carats.

Value: The Victory diamond is currently auctioned at Sotheby’s for at least $25 million.

8. The Golden Jubilee Diamond

Discovered: The Golden Jubilee was found in the Premiere Mine in South Africa in 1985, the same mine where the Cullinan was discovered.

Famous for: The Golden Jubilee diamond is the world’s biggest cut and faceted diamond to date. Weighing 545.67 carats, it is 15.37 carats larger than the famous Cullinan I diamond. In 1997, the diamond was brought to the King of Thailand during his 50 ^thyear as King. It was presented to the King by the Thai Diamond Manufacturers Corporation.

Value: The Golden Jubilee diamond is currently valued at $12 million.

9. The Vargas Diamond

Discovery: The Vargas Diamond was discovered in the San Antonio River in Minas Gerais, Brazil in August 1938. Two gold miners found the diamond and sold it to a dealer for $56,000, who later sold it to a Dutch group for $235,000. It was named the Vargas diamond after the Brazilian president Getulio Dornelles Vargas.

Famous for : The 726.6 carat diamond was cut into 29 smaller diamonds. The largest was a 48.26 carat emerald cut, which was named President Vargas. The diamonds are D color, structurally perfect and chemically pure.

Value: The 28.03 carat President Vargas IV was sold for $781,000 in 1992, while the 25.4 carat President Vargas VI was sold for $396,000.

10. The Jonker Diamond

Discovery: The Jonker diamond was discovered at the Elandsfontein mine in South Africa in January 1934, just 5 kilometers away from the location of the Cullinan diamond.

Famous for : Weighing 726 carats, the Jonker is the fourth biggest rough diamond ever found. It was cut into 13 gems; the largest called the Joker I, weighing 149.9 carats. Later it was re-cut into a 125.35 carat piece. It is a D-color flawless diamond and was bought by Egyptian King Farouk in 1949, eventually making its way to an anonymous buyer from Hong Kong who bought it for $2,259,000.

Value: Current estimated value is $2.25 million.

11. The Jubilee Diamond

Discovery: The Jubilee was discovered in 1895 at the Jagersfontein mine in South Africa, the same mine which yielded the Excelsior diamond.

Famous for: The Jubilee is the world’s sixth biggest diamond and weighs 245.35 carats. It was originally called the Reitz diamond, after Francis William Reitz, who was the current president of the state where the diamond originated. It was renamed the Jubilee in 1897 in honor of Queen Victoria’s 60 ^thcoronation anniversary. The rough stone was an octahedron which weighed 650.80 carats. It was the largest diamond until 1905 with the discovery of the bigger Cullinan diamond.

Value : Undisclosed.

12. The Sefadu Diamond

Discovery: The Sefadu was discovered in 1970 in Sefadu, Sierra Leone.

Famous for : In the present time the Sefadu is the world’s biggest rough diamond, and the seventh biggest diamond to be discovered. It weighs 620 carats and remains uncut. Although its value would greatly increase once it is cut and polished, its owner Lazare Kaplan has chosen to keep it in its original state as a mineral specimen.

Value: Unknown.

13. The Kimberley Octahedron

Discovery: The Kimberley Octahedron was discovered in the Dutoitspan mine in the Kimberley region of South Africa in 1964.

Famous for: At 616 carats, it is the world’s biggest naturally formed diamond in the octahedral form, and currently the 14 ^thbiggest gem quality rough diamond in the world. It remains uncut up to this day, and is currently on display at the Big Hole Museum in South Africa.

Value : Unknown.

14. The Lesotho Promise Diamond.

Discovery: The Lesotho Promise was discovered in August 2006 at the Letseng mine in Lesotho.

Famous for: It is the largest diamond to be extracted in the current century, and the world’s 15 ^thbiggest diamond. The stone is rated D color, and was sold for $12.4 million to the South African Diamond Corporation. The largest diamond cut from the rough stone is 75 carats. 26 diamonds in total were fashioned from the original stone.

Value: Estimated at $20 million.

15. The Lesotho Brown Diamond

Discovery: The Lesotho Brown, or simply the Lesotho, was found in the year 1967 at the Letseng mine in Lesotho.

Famous for : The rough stone weighed 601 carats. It was cut into smaller gems with the largest at 71.73 carats called the Lesotho I. One of the smaller diamonds, the Lesotho III which weighs 40.42 carats was given to Jackie Kennedy and it was sold for $2,587,500 at an estate auction in 1996. The largest stone, the Lesotho I remains unsold.

Value: Estimated at $5 million.

16. The Centenary Diamond

Discovery: The Centenary Diamond was found in the South African Premier mine in July 1986, and was named in honor of the centennial celebration of De Beers Consolidated Mines in 1988.

Famous for : The original rough stone was 599 carats, and was described as “perfect in color”, being a grade D colorless stone. Its final form was presented in May 1991, weighing 273.85 carats.

Value: Estimated at $90 million.

17. The Spirit of De Grisogono

Discovery: The Spirit of De Grisogono was found in Central African Republic.

Famous for : It is the world’s biggest cut black diamond to date, and the fifth biggest diamond. The rough stone weighed 587 carats, and was cut by the famous jeweler De Grisogono. The mogul cut gem weighs 312.24 carats and is set on a ring which was sold for an undisclosed amount.

Value: Unknown.

18. The Letseng Legacy

Discovery: The Letseng Legacy was discovered in September 2007 at the Letseng mine in Lesotho.

Famous for: The rough diamond was 493 carat when discovered, which makes it the world’s 18 ^th biggest diamond found. It was bought by the Graff-SAFDICO group for $10.4 million.

Value: $10.4 million.

19. The Kimberley Diamond

Discovery: The Kimberley was discovered in the Kimberley mine in South Africa.

Famous for : The champagne colored rough stone was originally 490 carats. Its final cut led to a 55.09 carat flawless emerald shape.

Value: Estimated at more than $500,000.

20. The De Beers Diamond

Discovery: The De Beers was discovered in the De Beers mine in South Africa in 1888.

Famous for : The rough stone weighed 428.5 carats, and was cut into a 234.65 carat  cushion cut. It is the world’s second biggest cut yellow diamond, and the biggest yellow cushion cut diamond. It is also the seventh biggest faceted diamond (regardless of color). The diamond became part of a necklace commissioned by the Maharaja of Patiala, but eventually disappeared without any traces.

Value: Estimated to be at least $4.5 million.

21. The Regent Diamond

Discovery: The Regent was discovered in 1698 at the Kollur mine in Andhra Pradesh in India.

Famous for : After several attempts to sell the stone to members of the European royalty, it was finally bought by the Duke of Orleans, French Regent Philippe II for £135,000 (equivalent to £18,337,900 as of 2015). It eventually became a part of the Crown Jewels of France, and is now on display at the Louvre.

Value: Estimated at £48,000,000