MINER Petra Diamonds said it recovered a high-quality 25.5-carat blue diamond at its Cullinan mine , near Pretoria, sending its shares up as much as 5%.
Blue diamonds are extremely rare and Cullinan mine has produced some that have fetched high prices, including a 26.6-carat rough stone that sold for $9.49-million (R86.9-million) in 2009.