The World's largest octahedral diamond is from the Du Toitspan Mine.

Whilst researching the Du Toitspan Mine in South Africa for my second WW2 spy thriller The Imperative , I note that it produced the largest naturally formed octahedral diamond crystal in the world back in 1964. It is a 616 carat yellow crystal named The Kimberley Octahedral. The owners of the diamond, De Beers Consolidated Mines, who were aware of the rarity of this exceptional find decided to preserve it for the sake of posterity. The chances of finding a similar diamond of such enormous size is extremely remote. The diamond is exhibited in the "Diamond Vault" of the visitor’s centre at the 'Kimberley Big Hole', Kimberley, South Africa.