It was found at Rio Tinto’s Argyle diamond mine in western Australia’s East Kimberley region.
The rare stone – already named the Argyle Pink Jubliee, presumably after the Queen’s historic achievement this year – is 12.76 carats, making it the largest pink diamond ever found in Australia.
It is currently being cut and polished in Perth in preparation for a team of international experts who will grade the diamond, and it will then be sold later in the year after touring the world.
A Rio Tinto spokesperson said that, although 90 per cent of the pink diamonds in the world come from the Argyle mine, finding a diamond of this calibre was “unprecedented”.
The Argyle Pink Jubilee is similar to the Williamson Pink – the diamond that Queen Elizabeth II received as a wedding gift.
To put the new discovery in context, a 24.78-carat pink diamond sold for £29 million in 2010, making it the most expensive jewel ever.