Columbus Gold reported that a preliminary economic assessment (PEA) of the Montagne d’Or gold deposit on its Paul Isnard project in French Guinea supports average production of 273,000 oz/y of gold over the first 10 years of operation. Life-of-mine production over a period of 13 years would total 3.05 million oz.
Capital costs to develop a mine on the Montagne d’Or deposit are estimated at $366 million, including a $44 million contingency. All-in sustaining costs are estimated at $711/oz of gold produced.
The Montagne d’Or open-pit mine is sized to produce 12,500 metric tons per day (mt/d) of mill feed, with a low-grade stockpile to ensure high-grade feed is processed first. Conventional open-pit mining methods would create a pit approximately 2.5 km long by 500 m wide by 400 m deep. Mined volume would total 127.7 million m3, with a 5:1 strip ratio, waste to ore. Life-of-mine grade would average 1.8 g/mt gold.
The PEA base case calls for power supply from on-site generation at a cost of $0.20/kWh, however, a connection to the power grid 125 km from the project at the port of Saint-Laurent-du-Maroni would reduce the cost to $0.11/kWh. This option is currently at an advanced stage of study. Due to a low ball mill work index of 12 kWh/mt, Columbus Gold anticipates that the mill will have a competitive processing cost in either power-supply scenario.
Columbus Gold intends to start a feasibility study of Montagne d’Or development in the third quarter of 2015 and targets completion in the fourth quarter of 2016. The project’s preliminary Environmental and Social Impact Assessment (ESIA) has been completed, and delivery of the final ESIA is anticipated by the fourth quarter of 2016.
Feasibility study work is being funded by Nord Gold N.V. as part of a minimum $30 million exploration and development program pursuant to earning a 50.01% interest in the project.
Columbus Gold Chairman and CEO Robert Giustra said, “The advancement of the Montagne d’Or Gold deposit to the PEA stage achieves a significant milestone that clearly indicates the potential to develop a low-capex gold deposit with scale and good grade at below industry average cash costs. Additional drilling and continued refinement of operating costs, including various energy proposals in the upcoming feasibility study, hold the potential for a reduction in overall costs.”