A new gemstone sets a world record. A rare diamond known as the Pink Star has been sold in Hong Kong for more than $71m (£57m). This has set a new world record for any gemstone at auction.

According to a report, Pink Star is oval-shaped 59.6 carat stone. This was bought in mere five minutes' bidding at Sotheby's. The buyer was Hong Kong jewellery retailer Chow Tai Fook Jewellery.

Pink star is the largest polished diamond in its class to go under the hammer.

Previously, Pink star has been sold for $83m in Geneva in 2013 but the buyer later defaulted. The record until now was held by the Oppenheimer Blue, which sold for $50m last May.

The Pink star was found by De Beers at a mine in Africa in 1999 and is cut over a period of two years. The bidding for the gem began at $56m.

Alexander Breckner, head of diamonds at jewellers "77 Diamonds", told the BBC that the stone is exceptional. "It's the largest pink diamond ever found in the history of humankind. It's an incredible colour to it. The sheer size of the stone already makes it so rare and so beautiful."

Previous records set by a Gem stone

May 2016: Oppenheimer Blue : sold at $50.6m (£34.7m at the exchange rate then current). The buyer's identity is unknown.

November 2015: The Blue Moon, a 12.03-carat ring-mounted with cushion-shaped blue diamond, bought by Hong Kong tycoon Joseph Lau at a record price of $48.4m (£31.7m). He renamed it the "Blue Moon of Josephine" after his 7-year old daughter.

May 2015: The Sunrise Ruby, a 25.59-carat "pigeon blood" coloured gemstone sold at $30m (£19.1m) to an unnamed buyer. With the given price, it became world's most expensive precious stone other than a diamond.

November 2013: The "largest vivid orange diamond in the world", according to Christie's, attracted the highest price paid per carat for any diamond at auction, selling for $35m (£22m), or $2.4m (£1.5m) per carat.

November 2010: The Graff Pink, a 24.78-carat "fancy intense pink" stone, auctioned for $46.2m (£29m). At the time it was believed to be the most expensive gemstone bought at auction. It was sold to the well-known British dealer Laurence Graff.

Source: BBC News