A rare diamond has been unearthed from a diamond mine in South Africa. The stone is unusual partly because it's blue - which is one of the rarest diamond colours. It's also enormous - weighing in at 29.6 carats. And it is said to have outstanding tone, clarity and saturation.
The stone could fetch £10.3 million. But how does it compare to the most expensive diamonds ever sold?
The owner of the mine, Petra Diamonds Limited, released a statement announcing the find at Cullinan mine in South Africa.
It said: "The stone is an outstanding vivid blue with extraordinary saturation, tone and clarity, and has the potential to yield a polished stone of great value and importance." It added that "Blue diamonds are among the rarest and most highly coveted of all diamonds." CBS reported the company's chief executive as saying it was probably the most significant blue diamond that the company had ever recovered.
The BBC estimates that it could be worth £10.3 million: the company unearthed a stone of similar size and it sold for this sum last year.
However, Diamond Expert, and founder of Vashi.com, Vashi Dominguez told AOL: "Depending on when it's auctioned, it could be worth £18 million. The stone is an exceptional vivid blue colour of outstanding quality, therefore there is the potential for it to yield one of the world's most special polished diamonds."
Most expensiveIt's an impressive stone, but it's not a patch on the most expensive diamond in the world, which sold at Sotheby's for a record £83 million in November. That was The Pink Star, a 59.6 carat pink diamond, which was renamed The Pink Dream by the buyer.
Then there's the Archduke Joseph, a 76.02 carat colourless diamond which sold for $21.4 million in 2012, setting a record for the most expensive colourless diamond per carat ever sold at auction.
And if you're looking for impressive blue diamonds, there's the Wittlesbach-Graff, a 31.06 carat stone which sold in 2008 for $24.3 million.
It isn't the most impressive diamond to come from this mine either. That title is held by the Cullinan Diamond found in 1905, which was the largest diamond ever found. The rock was cut into 106 diamonds, including the the First Star of Africa, which is 530 carats and is set in the Queen's crown, and the Second Star of Africa at 317 carats, which is set in her sceptre.
It might not be the most exiting recent find either. How could it match the thrill of the 12-year-old at a diamond hunting tourist attraction in Arkansas, who picked up a £7,700 stone within ten minutes of looking last summer.