Rare stones are just three of six to be certified by GIA since 1983.
Rio Tinto is set to sell three rare red diamonds from its Argyle Diamond mine in Australia at its annual tender of rare coloured stones later this year.
The sale marks the first time that red diamonds have been offered at a tender in the 30-year history of the Argyle Diamond mine. Rio Tinto will host world previews of the stones ahead of the tender.
Argyle Pink Diamonds manager Josephine Johnson said: "Since mining began in 1983 only six diamonds certified as fancy red by the Gemmological Institute of America have been presented for sale at the annual tender. To have three of these rare red diamonds in one tender is a very special moment in time.”
The annual Argyle Pink Diamonds Tender showcases the best stones of a year’s production from the Argyle mine in Western Australia.
This year’s highlight, among the red stones, is the 1.56ct round diamond named the Argyle Phoenix in honour of the newly commissioned Argyle underground mine.
Johnson added: “The intrinsic beauty and unrivalled colour intensity of this red diamond is symbolic of its East Kimberley birthplace and the treasures that lie within the depths of the new underground mine."
For the first time in eight years the tender will also feature a diamond of more than three carats – the 3.02 carat radiant, fancy intense orangey-pink diamond, named the Argyle Imperial.
A blue heart shaped diamond totalling 0.71 carat blue heart-shaped called the Argyle Celestial is expected to be sold with a matching heart-shaped fancy pink diamond from the collection.
The total 2013 Argyle Pink Diamonds Tender will feature 64 diamonds, including 58 pink diamonds, three fancy red diamonds and three blue diamonds. All 64 diamonds in this year’s collection were cut and polished in Western Australia by Rio Tinto’s craftsmen.
Tender viewings will be held in Perth and Hong Kong with previews in Sydney, New York and Tokyo. Bids are set to close on October 8 2013.