Picture: ISTOCK
Picture: ISTOCK

JSE-listed Namibian investment holding company Trustco said on Thursday morning it had sold the 29th-largest diamond ever discovered for $16.5m.

On November 10, Trustco announed its 51%-owned subsidiary Meya Mining had discovered a 477-carat diamond in the Kono district of Sierra Leone.

Trustco said what it called the "Meya Prosperity Diamond" had been sold to an unnamed "first-tier global jewellery brand" which had agreed to pay an additional bonus to the $16.5m price if the largest polished stone cut from the rough diamond is graded "D flawless".

Trustco is heading to be the JSE’s second-best performing share for 2017 with a gain of 111%, placing it behind Kumba Iron Ore, which has risen 120%.

Besides announcing the sale of the Meya Prosperity Diamond, Trustco said in Thursday’s operating update it had recovered 3,333.23 carats from the first 5,162 tonnes of kimberlite processed from its Meya River project. This included the giant 477-carat diamond.