• CENTRAL AFRICA | GABON French mining company Eramet’s Gabon-based subsidiary and manganese miner Compagnie Minière de l’Ogooué, (Comilog), together with the Gabonese government and its state-owned mining company Société Equatoriale des Mines (SEM), have partnered to undertake a strategic review of the Maboumine niobium and rare earths project to evaluate how to best develop it. CHANTELLE KOTZE writes. IN SHORT The Maboumine polymetallic project is rich in size as well as niobium and rare earth concentration. T he project is one of many currently being undertaken in the Central African country to rebalance its largely oil and gas driven economy to a more natural resource diverse economy. Located near Lambarene in central Gabon, the world-class Mabounié polymetallic ore deposit has, since 2005, been developed by Maboumine, a company owned partly by Comilog (76%), the Gabonese state (15%) and other minority shareholders (9%), under the leadership of Eramet, in partnership and with the strong support of Gabonese authorities and local communities. The Gabonese state acquired the second largest stake (15%) in the project in 2014, as a means to add to its investment portfolio for the benefit of the Gabonese minerals sector. In an exclusive interview, SEM CEO Fabrice Nze-Bekale notes the extensive development effort carried out so far has enabled the establishment of a sound knowledge of the deposit while developing an innovative and bespoke metallurgical process able to recover most of the value metals embedded in the ore. The deposit was historically explored for phosphates some 20 years ago by SOMIMO (Société Minière Du Moyen Ogoué) – a JV between the State and foreign investors that was formed in 1992 to investigate phosphate mining potential in Gabon. Deposit specifics MINING REVIEW AFRICA Comilog, explored the deposit for rare earths and niobium for more than 10 years. During this time Eramet and Comilog carried out several exploration drilling surveys – drilling more than 1 000 holes and extracting over 40 kg of ore. Moreover, extensive geotechnical and hydrogeological surveys have also been performed inside and outside the deposit to validate project site selection. “The Mabounié deposits’ ore mineralogy is complex but well understood,” says Nze-Bekale, adding that the niobium is contained mainly in complex to “ The Mabounié ore deposit is arguably one of the most attractive known deposits in the high value metals sector,” Fabrice The deposit was subsequently acquired by Eramet, which through its subsidiary 26 Ore drilling at the Mabounié site | Nze-Bekale SEPTEMBER 2016 process pyrochlore and ferrocolumbite rock, and rare earths hosted in pyrochlore, apatite and crandallite. Maboumine benefits from a very favourable rare earths distribution compared to other projects with a high content of “magnet rare earths” including neodymium and praseodymium – two rare earth metals higher in value because of their magnetic properties. The Mabounié ore deposit is rich both in size (>$US50 billion) and concentration ($1 400/t). “It is arguably one of the most attractive known deposits, in the high value metals sector,” says Nze-Bekale. The Mabounié ore deposit has indicated mineral resources of 2.3 Mt of niobium petoxide (Nb 2 O 5 ) grading at 1.2% and a rare earths mineral resource of 2 Mt of rare-earth oxides (REO), grading at 1%. These mineral resource estimates, which were independently certified in 2015 by Canada-based mineral resource