London - Petra Diamonds said revenue rose 24% for the year to end June as higher rough diamond prices and sales outweighed a decline in production.
Mine revenue rose to $221m and would have jumped 55% if the exceptional sale of the $35m Cullinan Heritage diamond was excluded from the 2010 figures.
Production declined 2% to 1 116 965 carats and the company, the largest diamond producer on London's junior AIM market, expects output to double in the 2012 financial year.
Petra expects to produce more than 2 million carats in the current financial year, chief executive Johan Dippenaar told Reuters on Tuesday.
The company will provide a more detailed guidance at the time of its full-year results once it has a clearer idea of when the Finsch mine acquisition in South Africa will start to contribute.
It expects to close the acquisition of the Finsch mine in coming weeks.
Petra plans to move to the London Stock Exchange's Main Market by the end of 2011.