Prospective buyers in Hong Kong are preparing to be dazzled by a first glimpse of one of the largest and “most coveted” red diamonds ever discovered. The Argyle Everglow is a 2.11 carat red diamond mined by industry giant Rio Tinto from the Argyle Diamond Mine in Western Australia – the world’s largest source of pink diamonds. Red is considered to be the rarest diamond colour as less than one carat of such stones are extracted from the mine each year. The diamond was found in January 2016 and is expected to be one of the last discovered before the mine closes in 2021. It was the largest red diamond found by the company. The rare jewel was part of a collection of 58 diamonds of various colours. “It was over four carats in the rough, and the depth of colour was very rich. In fact we called it ‘Everglow’ because it looked like it glowed,” Rio Tinto Diamonds global marketing director Josephine Johnson said. The diamond is expected to sell for “millions [of US dollars] per carat”, she added. Red diamonds are created by a rare process in the stone’s atomic structure, known as “plastic deformation”. Special equipment is required to cut such gemstones since they are much harder than ordinary white diamonds. Mystery diamond buyer revealed: Joseph Lau spends US$48m on ‘Blue Moon Diamond’ for daughter, 7 Red is considered an auspicious colour in China and the diamond is expected to attract bidders from around the country. Coloured diamonds are also a favourite of Japanese bidders, especially stones in cherry blossom tone. Unlike the traditional auctions of bigger auction houses, Rio Tinto is inviting bidders to a five-star hotel in the city – by invitation only and under tight security – to examine the diamond until September 17. Potential clients can then place a bid through a secure online portal, which closes on October 11. All bids are anonymous and can’t be seen by other bidders. The company will only be able to view the highest bid when the auction closes. Man who swallowed diamonds in HK$89 million attempted robbery arrested as shopkeeper found unconscious Australian jeweller and designer John Calleija has bid on multiple coloured diamonds in the past and hopes to be able to purchase the Argyle Everglow for his clients. “As a designer that stone has to talk to me; I have to see something in it that is remarkable. It’s a natural instinct as soon as you view the diamond,” he said. “It’s so much like other things such as a suit or art – you either connect to it or you don’t. They all have a soul of their own.” Calleija said that if bidders were unsuccessful, a flurry of phone calls would be made among them to identify the winner and see if he or she would be willing to sell off the diamond. In 2015, coloured diamonds came under the spotlight in the city when property tycoon Joseph Lau Luen-hung named three precious stones he bought at auctions after his daughter Josephine.