This project is owned by Xtract Resources PLC and is located in western Manica Province of Mozambique, some 4 km north of the town of Manica within the Beira Corridor. The project entails the construction of an open pit gold mine feeding the oxide material to a leaching plant and the sulphides to a flotation plant. Whole-ore leaching of oxides is expected to achieve a recovery of up to 95% while flotation of sulphides showed recoveries of approximately 94%.
The nature of the orebody influences the mining method and extraction methodology. The mineralised zone is confined by a meta-conglomerate hanging wall unit, and a carbonate altered, meta-basalt footwall. The basic geologic units have been divided into the talc schist footwall and metaphyllite hanging wall. The orebody is sub-vertical with the dip ranging from 70° N to 75° N. The required production plant feed rate for the production scheduling is 42 ktpm and the final pit has resulted in a life of mine of seven years. The project has a Mineral Reserve of 3.21 Mt with a life of mine average delivered grade of 2.62 g/t Au.
Minxcon conducted a Definitive Feasibility Study for the design of the gold mine. The economic cut-off grade from the pit optimisation was calculated as 1.05 g/t Au. All material between 0.4 g/t Au and 1.0 g/t Au was classified as low grade material. The low grade material was not considered for this investigation and will be stockpiled as strategic ore to be utilised at the end of the mining operation if viable in future economic conditions.
A decision was made that the ore will be stockpiled into different grade categories because of the varying ore grades in the orebody. This will provide the flexibility of targeting a plant feed head grade by blending ore from the different stockpiles. In-pit assaying will be implemented to achieve the classification of different grades. The blending strategy provides the ability to feed the plant with the required head grade from the different grade stockpiles.
Minxcon has invoked to stockpiling to ensure the highest possible oxide and sulphide grades report to the plant in advance to the lower grade. This enables the highest cash flow and margins being realised in earlier years. The valuation has determined that the oxides provide a two year window of high margin material which will be available to pay back the peak funding requirement of USD44 million within two years.
Minxcon provided project critical information to the power plant feasibility study ensuring continued communication, information sharing, project coordination and integration throughout the duration of the project.