It seems like just about everyone is catching on to the rarity of the Argyle Pink Diamonds and such they are becoming increasingly difficult to procure.
Quoted from the Argyle Website:
An Argyle pink diamond is admired as the most concentrated form of wealth in the world.
One and a half billion years ago, forces of nature rewarded the land in Western Australia’s vast Kimberley, with pink diamonds. The exact story behind their formation remains largely a mystery, adding to their allure and intrigue.
Diamonds were first discovered in the region in 1979, when a geologist noticed a diamond embedded in an anthill. A Rio Tinto owned mine was built on the site in 1985, and of the 600 million stones it produces each year, just one tenth of one percent is pink.