Greenstone Gold Mines – a 50:50 joint venture of Centerra Gold and Premier Gold Mines – has received approval from the provincial environment ministry for development of the Hardrock gold mine 2 km south of Geraldton, Ontario. Federal approval was received late last year.
An open pit and 27,000 t/d mineral processing plant are planned. The pre-production capex will be near C$1.25 billion to create a project that produces an average of 300,000 oz. of gold over a 14.5-year mine life. The project has a an expected after tax net present value (5% discount) of $818 million, an internal rate of return of 17.5%, and a payback period of 4.5 years.
The project has probable open pit reserves of 141.7 million tonnes grading 1.02 g/t gold for 4.6 million contained oz. Both the indicated and inferred estimates contain underground as well as open pit resources. The cut-off for pit material is 0.30 g/t and for underground is 2.0 g/t. Using those numbers, the indicated resource is 25.1 million tonnes at 2.29 g/t gold for 1.9 million contained oz., and the inferred portion is 21.7 million tonnes at 3.55 g/t gold for 2.5 million contained oz.
The 2019 work plan for Hardrock is to advance the permitting process, proceed with detailed engineering, drill a further 18,000 metres to update reserve and resource estimates, incorporate the optimization work that was done over the past two years, and update the project economics.
(This article first appeared in the Canadian Mining Journal)