Diamond mining company Petra says it has found an "exceptional" 122.52-carat blue diamond. The "unique" stone was found at the Cullinan mine near Pretoria in South Africa, the company said.
The crystal is being analysed in order to gauge its value, and the company will not put it up for sale before its financial year runs out at the end of this month. Petra Diamonds shares jumped 6.5% after the announcement on Friday morning.
The highest price on record for a rough diamond is $35.3m
507.55-carat rough recovered from Cullinan in 2010 and sold for $ 35.3m