JOHANNESBURG (miningweekly.com) – Aim-listed diamond mining and exploration company Firestone Diamonds could recover 1.2-million tons a year from a new openpit mine in Lesotho, a definitive feasibility study has shown.

The company said production at Liqhobong could start in 2015 and that the mine would operate for 15 years.

The study has estimated capital expenditure of $167-million for the plant and associated infrastructure. It is envisaged that the plant and infrastructure will be completed in about 24 months, with commissioning expected in the second half of 2015.

The project has an estimated pretax net present value of $441-million, applying an 8% discount rate, with a 44% internal rate of return with 28-month payback period.

Firestone Diamonds has a 75% interest in the project with the government of Lesotho holding the remaining 25%.

Firestone CEO Tim Wilkes said the results confirmed management's belief in the robustness of the project. “There could also be considerable upside from the recovery of larger special diamonds that have been catered for in the design of the new treatment plant.”

The company said it was progressing discussions with debt providers and considering other marketing arrangements to minimise dilution to shareholders.

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