JOHANNESBURG (miningweekly.com) – Aim-listed Premier African Minerals expects to update its resource estimate at its RHA tungsten mine, in Zimbabwe, before month-end, following the completion of an underground implementation study.

The preparation of the update was delayed following the need to review the openpit ore for purposes of possible bulk mining following successful test work using X-ray transmission technology.

The study, prepared by RHA and Whaleside Shaft Sinkers Zimbabwe, showed that the company would need $406 000 in capital cost for underground development, while confirming that the project schedule for equipping the vertical shaft hoist and commissioning of operations on 870 level remained on schedule for February.

Further, the study highlighted that the miner would follow a six-month underground mining plan on 926 level, while re-equipping the vertical shaft to 870 level.
 
"RHA was always planned, in the longer term, to be an underground mine. Unforeseen developments during the initial openpit operations led the company to accelerate the move to underground mining.

“This change in strategy has resulted in the need to finance company overheads for an extended period without recourse to cash flow generated from the openpit and finance substantial additional debt generated by RHA,” CEO George Roach said.

He added that Premier had successfully extracted and stockpiled ore from underground since late November and now anticipated RHA to generate positive operational cash flow during the course of this year.

The company also anticipated a liquidity event in relation to its interest in Circum Minerals. “These two events should significantly strengthen the company's balance sheet,” Roach noted.
 
RHA's implementation plan was based on targeting the processing of about 32 000 t of run-of-mine ore at an average grade of 6.20 kg/t to produce 249 t of concentrate at 63% tungsten trioxide over a six-month period from February.