BHP Billiton released its annual production report. According to the report, diamond production dropped in the past year. The year that ended in June 2011 saw an 18% decline as compared to the year that ended in June 2010. The report attributed the drop to lower average ore grades.

Ore grades have proven to be variable since they come from a mix of open pit and underground mining. BHP Billiton stated in its report that it expects lower average ore grades to impact the Ekati diamond mine's production in the 2012 fiscal year.



In the second quarter of 2011, BHP Billiton saw production of 576,000 carats. This was a 5% increase over the first quarter of the year. However, the second quarter of 2011 produced 22% less than the same period for the previous year.