Study Supports Restart of Aurizona Mine in Brazil

Workers install a CIL tank at the Aurizona gold operation
prior to the mine’s transition to care and maintenance status
in 2015. (Photo: Luna Gold)
Luna Gold Corp. has reported the results of a prefeasibility study (PFS) of a potential restart of operations at its Aurizona gold mine in northeast Brazil. The mine has been on care and maintenance since August 2015. The PFS mine plan would continue mining in the existing Piaba open pit, deepening the pit and mining harder rock types that will be amenable to treatment in an upgraded processing plant following installation of a new comminution circuit.

The Aurizona redevelopment project has 969,000 oz of gold in proven and probable mineral reserves at an average diluted grade of 1.62 g/mt gold and 1.60 million oz of gold in measured and indicated resources, inclusive of reserves, at an average diluted grade of 1.67 g/mt gold.

The upgraded processing plant will have throughput capacity of 8,000 mt/d, with production forecast to average 150,000 oz/y over the first five years of operation. Initial capital costs to restart operations are estimated at $146 million, including a new mine fleet. All-in sustaining costs of production are estimated at $708/oz of gold produced.

Procurement and construction of the new components and equipment for the restart is expected to take 18 months. The PFS recommends that the Aurizona restart project continue to its next phase with the preparation of a feasibility study. Additional geotechnical field work is recommended to support suggested pit slopes, waste storage facilities, and tailings dam raises; and additional metallurgical testwork is recommended to confirm preliminary indications that the presence of arsenic does not materially impact gold recovery in the process plant. A $2.4-million program has been outlined by Luna to address these and other items, with the objective of issuing the feasibility study by end of the first quarter of 2017 and targeting a first gold pour in the second half of 2018.

As featured in Womp 2016 Vol 10 -