DiamondCorp (LON:DCP) is still targeting the start of underground mining at the Lace Mine in South Africa for the end of the first half next year despite the ongoing strike.
The strike, by AMCU miners, over the appointment of two further salaried shop stewards, will cause a one-week delay every fortnight it continues, the firm said.
"Until such time as the strike ends, tunnelling in the UK4 block and processing of kimberlite ore is continuing with non-AMCU members, DiamondCorp said.
It added: "Installation of the underground conveyor belt is unaffected by the strike action. Final commissioning of the conveyor will be dependent upon development schedules but the commencement of mining of the UK4 block is currently still on target for the end of H1 2015."
The firm said management met last week with AMCU officials in a bid to end the action, but no agreement has yet been reached.
Broker Sanlam said the firm's update was to keep the market informed.
"Although there is as yet no resolution, management is standing firm and will not bow to AMCU’s demands.
"Fortunately, DiamondCorp’s strong balance sheet allows a strong stance. Development will continue with the non-AMCU workforce focusing on the UK4 block from where early production and cashflows will come in 1H15."