The output was recovered from 0.5 million tonnes of ore mined from Diavik located in Northern Territories of Canada.
It demonstrates 21% increase in carats when compared to 1.6 million carats from 0.5 million tonnes of ore processed in the comparable quarter of 2012.
The increase is attributed to the improvement in kimberlite pipe grade. The average grade of ore processed increased to 3.87 carats per ton, against 3.03 carats per ton in the corresponding quarter of the previous year.
Meanwhile, Dominion Diamonds has secured approval for the mine plan and capital investment for 2013 from its joint venture partner Rio Tinto.
It estimates annual production of 6 million carats from the mining and processing of nearly 1.6 million tons of ore along with additional 0.2 million tons processed from stockpile ore.
Also, it expects to mine ore of 0.7 million tons, 0.5 million tons and 0.4 million tons from kimberlite pipes A-154 North, A-154 South, and A-418, respectively.
However, it has blocked the development of A-21 citing the identification of extensions to the existing pipes.