Million dollar Argyle red diamond coin unveiled at Perth Mint
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12 July 2016 Rio Tinto is delighted to reveal the world’s first coin to feature a rare red diamond from the Argyle Diamond Mine. Known as The Kimberley Treasure and for sale at AUD$1million, the breath-taking collectable has been crafted from one kilogram of 99.99% fine gold, and features a radiant cut 0.54 carat red …