RAPAPORT... BlueRock Diamonds has recovered a 58.6-carat rough stone at its Kareevlei mine in South Africa, the company's largest to date.The stone is a D-color makeable - meaning it is suitable for having one large polished diamond cut from it - so the selling price will likely be "significant," said CEO Mike Houston in a Monday statement. He added, however, that it contained spotted black sulphide intrusions."The final value [will be] dependent upon the buyer's confidence of what cut stones can be recovered," Houston explained. The discovery of the diamond - which will go on sale at BlueRock's August tender - supports the company's belief that Kareevlei can deliver high-value stones in addition to its regular, run-of-mine goods, the executive asserted. Parcels of the standard material have sold for more than $400 per carat this year.Before this find, the miner's largest diamond was a 24.98-carat rough that it unearthed in 2019. The company also dug up two stones weighing 21.56 and 9 carats respectively earlier this month.Last week, BlueRock trimmed its production and revenue forecast for 2021, citing the impact of the recent South Africa riots on its operations.Image: The 58.6-carat diamond. (BlueRock Diamonds)