I read an interesting article about the "Once in a Blue Moon" diamonds produced in Australia. The article reads:
"Perth, Australia--Rio Tinto is set to showcase a selection of diamonds as rare as a blue moon.
A sale of blue diamonds known as the "Once in a Blue Moon" collection will be held as a closed tender in Hong Kong, Tokyo and Perth, Australia, prior to bids closing on April 8, according to a release from Rio Tinto.
While Rio Tinto's Argyle Diamond Mine in Australia is noted for producing both champagne and pink diamonds, "Once in a Blue Moon" is Rio Tinto's first collection of blue and violet diamonds, which are rarely found in nature.
"We are excited to showcase our first-ever collection of precious blue and violet Argyle diamonds, sourced from several years of production at the mine," Argyle Pink Diamonds Sales and Marketing Manager Josephine Archer said of the unusual offering. "It is an enchanting collection that will appeal to connoisseurs and collectors alike."
The "Once in a Blue Moon" collection includes a range of premium and commercial diamonds and features single cuts, a number of matching pairs and a selection of smaller diamonds, according to the release.
With only 10 years of production left for the Argyle mine, and only a sporadic occurrence of blue diamonds, Rio Tinto expects the "Once in a Blue Moon" collection to attract considerable attention, both in Australia and overseas."