African Mining Network

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AMN - TANZANIA: Mahenge graphite resource increases

Black Rock Mining continues to advance the Mahenge Graphite Project in Tanzania and has recently announced a 14% increase in total graphitic carbon (TGC) at the Cascades deposit. Utilising results from an additional 19 infill drill holes completed in late 2016, the Cascades resource now stands at 60.2 million tonnes at 8.1% TGC.

The updated Cascades estimate takes total Mahenge resources to 211.9 million tonnes at 7.8% TGC, making it the world’s fourth largest JORC-compliant graphite mineral resource. The total resource includes a high-grade component of 46.6 million tonnes at 10.6% TGC.

Cascades measured and indicated resources have increased by 25% to 32.9 million tonnes at 8.3% TGC with a high-grade portion of 14.6 million tonnes at 12.2% TGC. This includes a higher grade zone from surface of 12.9 million tonnes at 12.5%, which is likely to enhance mining grade in early years and deliver significantly lower operating costs.

Black Rock says the resource upgrade is expected to enhance the Mahenge PFS optimisation study which is currently being completed with results expected shortly.

The Cascades deposit contains substantially higher grade zones from surface than the Ulanzi high-grade component, providing the potential to deliver higher grades to a mining operation. As a result, Black Rock is assessing the impact of Cascade’s higher grade feed with an expected increase in free dig depth and higher proportion of coarse flake.

The Mahenge project has the potential to be mined from multiple zones at low strip ratios, high-graded to accelerate capital payback in early years and can be scaled up in future due to the large resource size.

Additionally, extensive metallurgical test work indicates that high purity concentrates up to 99% TGC can be made from a straightforward flotation circuit for both oxide and primary mineralisation.

Black Rock’s interim CEO John de Vries said, “The increase in the Cascades mineral resource estimate is extremely exciting in terms of how it will benefit the Mahenge Graphite Project. Whilst the 14% increase of Cascades mineral resource is pleasing, we are most excited by the 25% increase of proportion of measured and indicated resource.

“We believe this will directly assist in delivering industry leading low operating cash costs for a project that has already demonstrated its ability to deliver high purity product from conventional flotation circuit process.

“We believe that we have the best graphite resource of any development stage project and look forward to incorporating this development into the soon to be released PFS that considers a third milling module.”

www.blackrockmining.com.au