The Argyle Diamond Mine in Western Australia has released its precious pink offerings for the year as the world's rarest diamonds continue to become even scarcer.
Meanwhile, the mine may still be on the market with owner Rio Tinto reiterating a review of its diamond business as it continues to explore potential divestment options in its first half underlying earnings released last month.
Rio Tinto, the world's third largest mining company, first flagged a review of its diamond business in March.
Despite reporting diamond underlying earnings were up 107 per cent to $US203 million in the half year to June 30 compared to first half 2011, Rio Tinto chief financial officer Guy Elliott told reporters the company was still advancing potential divestment options.
Production from Argyle was up 24 per cent on first half 2011, which had been plagued by record wet seasons in the Kimberley region of WA through first half 2011.
Cut from the remote Kimberley Argyle Diamond Mine 56 single pink diamonds, two red diamonds and 19 lots of blue diamonds would now be showcased for tender in Perth, London and Hong Kong and with final bids received by October 15.
Argyle produces more than 90 per cent of the world's pink diamonds, which are even rarer than their white counterparts often commanding higher prices.
In February, Rio Tinto revealed it had discovered the largest pink rough diamond known in the world at Argyle, which went on to be called the Argyle Pink Jubilee.
Argyle Pink Diamonds manager Josephine Johnson said this year's tender collection was destined for investment portfolios or heirloom jewellery pieces.
Going with a "hero" theme, the collection's stars include the Argyle Siren, a 1.32 carat square radiant cut Fancy Vivid Purplish Pink diamond and the Argyle Satine, a 1.02 carat cushion cut Fancy Intense Purplish Pink diamond.
Rio Tinto Diamonds chief commercial officer Jean-Marc Lieberherr said the pink diamonds were a "diminishing natural treasure", in a statement today.
As well as the Argyle mine, Rio Tinto also has a 60 per cent interest in the Diavik mine in Canada, a 78 per cent interest in the Murowa mine in Zimbabwe and interest in an advanced diamond project in India.
Rio Tinto has targeted the first half of financial 2013 for first production from Argyle's underground project, which is expected to increase the mine's life to at least 2019.