PERTH (miningweekly.com) – Gold miner Theta Gold Mines has extended the prefeasibility study (PFS) into its Theta underground project to include the Rietfontein mine, in South Africa.

The PFS, which was announced in April of last year, originally only incorporated the Beta, Frankfort and CDM mines.

“The board is pleased with initial results from the Rietfontein PFS and has decided to add Rietfontein to the Theta Underground definitive feasibility study (DFS). It is expected that the addition will increase the production profile and mine life, along with further improving project economics,” said chairperson Bill Guy.

“Rietfontein high-grade ore was successfully mined up to 1945 using the shrinkage stoping method, producing 65 000 oz of gold from 227 000 t of ore, recovering more than 8 g/t. This method was also chosen for the PFS due to the proven methodology and relatively low ore dilution. The Rietfontein development will take place within the existing historical footprint, with minimal new surface disturbance.

“All workstreams for the Rietfontein PFS were completed, except for the metallurgical test work, due to backlogs currently experienced globally within labs. The DFS has been running alongside the Rietfontein PFS and solid progress has been made by the team.” 

The company told shareholders on Thursday that it would continue to build up its mining reserves during the next year by progressing Rietfontein and other mines through to DFS level. The company said that it remained focused on its target of reaching 160 000 oz/y within five years from a multi-mine development programme.

Theta Gold Mines has undertaken an off-market takeover of fellow-listed Focus Minerals, and is offering two of its own shares for every one Focus share held. The offer valued Focus shares at 36c each, representing a 41.2% premium to the company’s closing price on December 8.