Yanfolia Gold Mine

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This is the area covered by the Yanfolia Mining Permit and includes the Yanfolia Gold Mine which is comprised of multiple deposits, and covers and area of 2,300 km2. Hummingbird Resources acquired the project from Gold Fields in 2014 for US$20 million by way of 21.3m ordinary shares in Hummingbird at 56 pence/share, giving Gold Fields a 26% stake in Hummingbird. Hummingbird owns 80% of the project.

Regionally The Yanfolila Project is situated within one of several sub-basins along the eastern margin of the Greater Siguiri Basin. The GSB straddles the Mali-Guinea border and forms the western margin of the Birimian Volcano-Sedimentary Basin. Combined with the Archaean Kenema-Man Domain and the pan-African Benin-Nigeria Shield these form the West African Craton which is one of the major gold producing regions and gold rich areas in the world.

Locally the project is situated in the north-south orientated Yanfolila Belt which is located on the eastern margin of the Greater Siguiri Basin. The belt contains several sub-basins including the Komana Mafic Sub-Basin (KMSB) and the Kabaya Sub-Basin. The KMSB has an abundance of mafic rock units, basalt, and dolerite that have proven to host mineralisation and correspond to a broad gravity high. The KMSB hosts the majority of the Yanfolila gold targets and deposits that have been currently defined. It has a stratigraphic sequence of basalt, polymictic conglomerate, feldspathic sandstone, silt-shale, and a lithic-dominated greywacke. The stratigraphy of the KMSB is crosscut by Porphyry, granodiorite and diorite intrusions.

The Yanfolila Project is made up of seven main deposits, five of which have been subjected to resource definition drilling, modelling and grade estimation and reported as containing mineral resources compliant to JORC Code. As of March 2018 the estimated gold resource was 2.2 Moz @ 2.4 g/t and initial production will be 132,000 oz/year, which will decrease to 107,000 over a 7.5 year life of mine. Estimate waste rock is 106.7 Mt which will be deposited in waste dumps adjacent to the pits.

Mining will use conventional drill-blast and load-haul methods. African Mining Services appointed mining contractor for initial three year period, with option to extend by a further year. The contract is $112 million over the three years. Blasting is carried out using non-electric downhole delay detonators with ammonium nitrate fuel oil (ANFO) for dry holes and emulsion explosives for wet holes. AEL is providing an explosive storage and supply service to AMS.

Construction of the mine commenced in October 2016 with IMAGRI as the civils contractor. Mining commenced in August 2017, the Process plant was commissioned in November 2017 with SENET as the EPCM contractor. In December 2017 first gold was poured and the first shipments of gold doré bars to the refinery, and plant throughput was at 75% capacity.

Yanfolila ore is non-refractory and requires only a basic process plant that ultilizes gravity and CIL processes for the gold recovery. The design incorporates industry standard unit process operations consisting of primary and secondary crushing, closed-circuit ball milling with gravity concentration, intensive leach of the gravity concentrate, carbon-in-leach of the gravity tailings, elution, electro-winning, and smelting to produce gold doré.

Recovery of gold will be through a combination of gravimetric means and direct cyanidation. Gravity concentrate is treated through an intensive cyanidation process with the pregnant solution pumped to an independent gravity electrowinning circuit. The CIL circuit consists of seven tanks in series: one pre-leach tank and six CIL tanks.