A spectacular 507 carat white diamond has been recovered by Petra Diamonds at the Cullinan mine in South Africa.

507 carat diamond; photo by Petra Diamonds

Petra made the announcement this morning as they reported their preliminary annual results in which they declared that they had mined over 1 million carats of diamonds for the first time – a five-fold increase on the previous period.

But the operational statistics were easily overlooked on a day when Petra unveiled such an important gem, recovered just last week on Thursday 24th September.

The actual weight of the diamond is 507.55 carats, and although the stone has yet to be classified for its exact attributes, it is appears to be of exceptional colour and clarity – the key determinants of its value along with its obvious size.

At 507 carats (just over 100 grams) the diamond, which has yet to be named, is considered to be amongst the top 20 largest high quality rough diamonds ever found worldwide and ranks alongside other illustrious diamonds recovered at the celebrated Cullinan mine.

Cullinan has a special place in the history of diamonds as the source of the world’s largest gem diamond ever recovered, the ‘Cullinan’, at 3,106 carats rough.

It has also produced a further two of the world’s largest diamonds, the Golden Jubilee at 755 carats rough and the Centenary at 599 carats rough, and many other famous gems including the Taylor-Burton (69 carats polished).

The 507 carat diamond was recovered alongside three other special white stones of similar colour and clarity in the same production run: another very large stone of 168.00 carats and two other stones of 58.50 and 53.30 carats.

The Cullinan mine also produced a blue diamond which sold for a record price earlier in 2009.