BlueRock Diamonds - which owns and operates the Kareevlei diamond mine in the Kimberley region of South Africa - said production of run of mine material from its developed K2 pipe recommenced through the processing circuit on 8 Jan after the three-week Christmas break.
The company said that during the break it made a number of planned modifications to the crushing circuit designed to improve the method of feeding ore to the crushers.
It said these changes had now been tested and the crushing circuit has been back in full production since Monday (15 Jan).
Chief executive Adam Waugh said: 'We have used the time afforded to us by the Christmas break to make further improvements to our crushing circuit in order to increase throughput to the processing plant.
'I'm pleased to say that these improvements have been completed within the planned timeframe and budget.
'The sampling of the first tonnages from K5 during December were encouraging.
'Although K5 is smaller than K1, K2 and K3, early indications suggest a similar grade to K2. However, the average size of diamonds mined were much larger than those of K2.'
At 9:20am: (LON:BRD) Bluerock Diamonds Plc Ord 1p share price was -0.1p at 2p