20.08 carat Type IIb blue diamond recovered at Cul
20.08 carat Type IIb blue diamond recovered at Cullinan on 23 September 2019. (Petra Diamonds)
  • A 20.08 carat blue diamond found outside Pretoria in September has just been sold for R220 million.
  • The diamond is rated as a Type IIb stone, which are among the rarest and most valuable diamonds in the world.
  • It is only slightly lighter than the biggest blue diamond ever found, in diamond-rich Botswana.
  • For more stories, go to www.Businessinsider.co.za.

A rare 20.08 carat blue diamond found outside Pretoria has just been sold for R220 million, Petra Diamonds announced on Friday. 

The buyer is a leading diamond company that wishes to remain anonymous.

The gem-quality diamond, classified as a Type IIb stone, is among the rarest and most valuable diamonds, with very low levels of impurities. Only about 0.1% of all natural diamonds fall into the class.

The diamond was found in the Cullinan Diamond Mine, 40km east of Pretoria, in September.

See also: A massive, rare blue diamond has just been found outside Pretoria

The gem is only slightly lighter than the biggest blue diamond (of 20.46 carat) ever found in diamond-rich Botswana. Named "Okavango Blue", that diamond was found in the Orapa mine, the world's largest diamond mine by area.  

Bloomberg reported that a 30-carat blue diamond from Cullinan was sold for $26m (around R400 million at current exchange rates) in 2014.

Earlier this year, two massive yellow diamonds of more than 70 carats were found in Lesotho.

See also: Another monster diamond has been found in Lesotho

Petra Diamonds, which is listed on the London Stock Exchange, is South Africa's second largest diamond operation by production and has two other mines, in the Northern Cape and the Free State.

"We are very pleased with this result which is in line with our expectations and confirms the resilience in the value of very high quality blue diamonds, undoubtedly one of nature's rarest treasures. We look forward to following this exceptional stone's journey to its polished form, " Richard Duffy, Chief Executive of Petra, said.

See also: This record-breaking blue diamond from Botswana will only show imperfections under 10x magnification

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