Sierra Rutile said a new study of its mine in south west of Sierra Leone 'definitively' showed the world-class nature of the deposit and its ability to support multiple mining units.
The firm hailed the results as showing "exceptional feasibility study economics", including a $472m project pre-tax net present value.
The study returned a 27-year modelled project life, with significant scope for further extensions to the length of operations.
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It also showed low cash-cost operation at just $394 per tonne for the life-of-mine, including $219 per tonne for the first five years.
Chief Executive Officer John Sisay said the value of the project and its potential returns was impressive, and it further highlighted the inherent value of Sierra's existing, operating assets and near-term expansions.
"The low-cost nature of this project provides [the firm] with the opportunity to be an extremely profitable supplier of rutile to the market for the long-term," he said.
Rutile is predominantly used in the manufacture of white pigment for paint and plastics.
