Rockwell Diamonds Inc. said diamond output from its South African mines increased by 12 percent to 5,950 carats for the third quarter of fiscal 2013 ending November 31.

The rise came about despite having to deal with operational challenges and on-going industrial action at Tirisano, the firm said in a statement.

The Saxendrift operation delivered solid results and Klipdam made progress in addressing efficiency improvements, whilst Tirisano was placed on care and maintenance to preserve cash resources and allow management to focus on projects more in line with Rockwell's diamond value management strategy.

"Our overall throughput and diamond production volumes are consistently tracking closer to expectations, with stable overall diamond production of 5,950 carats for the quarter," says Chief Executive Officer James Campbell. "We are pleased with the continued performance at the Saxendrift complex, whose diamond yield increased by 59 percent, including the Bulk X-ray system that will be key to any future Rockwell mine developments in the region.

"We have taken decisive action to address Tirisano's persistent financial losses, putting our operations at the mine on care and maintenance in order to preserve our cash resources while appropriately planning the way forward. With the initial royalty mining contracts having made a positive contribution to overall production, we are working on additional agreements to extend these revenue streams."