This chicken egg-sized diamond, as called by Bloomberg, is a 507.6 carat rough stone that was found at Petra Diamonds’ Cullinan mine in South Africa in September. The diamond was part of a haul of four large stones found at the same mine in September. The other stones included a 168-carat stone, which sold for $6.28 million last week, and the rest have all been sold off. The other two stones sold for a total of $2.8 million. BMO Capital Markets is predicting a possible price of $31 million for biggest stone!
However, the diamond is not yet on sale, as Petra is still considering all angles before any potential sale of this extremely rare diamond. The company’s goal is to get the biggest price for the stone, but to also make sure that the stone’s legend lives on. Unlike small diamonds, large stones tend to carry the name of their source along with them, and it’s hard to say what the final carat count will be, since a lot of rough stones can lose half their carat weight in polishing. This means that depending on the flaws that diamond cutters will have to work around, it might end up becoming several cut stones which could each be worth a multi-million dollar price tag.