The mine is expected to more than double Petra’s annual production (steady state), contributing about 1.5 million carats per annum (mctpa) to group production, rising to nearly 2mctpa by financial year 2018.

Finsch is also expected to add about 125,000 carats per month to the company’s output after an initial three month bedding down period, adding at least 1mcts for the financial year 2012.

Petra CEO Johan Dippenaar said this acquisition is a further progression of the company’s strategy to build one of the world’s leading diamond mining groups.

"Finsch is an ideal addition to our portfolio, contributing a world-class mining operation with exceptional infrastructure, a major carat base and a sustainable, long-life outlook for the duration of our initial 18-year mine plan," Dippenaar said.