AVZ Minerals is drilling below the floor of the Roche Dure pit at its giant Manono lithium and tin project in the Democratic Republic of Congo hoping to upgrade a portion of the pegmatite ore to an indicated from inferred mineral resource category.
Previous drilling had defined more than 400Mt of potential ore at a startling grade of 1.65 per cent lithium oxide but it has been held over in the inferred category unable to be accessed after the pit floor became flooded, according to AVZ.
Whilst the company did not expect to see an increase in the overall resource tonnage, the ASX-listed company did say it expects a ‘wedge’ of the pegmatite ore will be upgraded to the Indicated Resource or possibly even the Probable Reserve category.
AVZ said it would rerun and optimise its existing mine design, once it receives assay results from the drilling which is now underway. Management are hoping some waste rock can be re-classified as mineable ore.
The company said there will be positive advantages from this work being undertaken with the most obvious being that two years of potential pre-stripping will be avoided and the payback period for financing will be positively impacted pro rata.
AVZ said it now expects a revised Ore Reserve Estimate and financial model to hit the streets around Christmas time this year.
In the meantime, the company said its engineering team was fine-tuning the mine’s plant location and design, with geotechnical work ongoing ahead of the future earthworks program.
AVZ said it was optimising the design of the site’s tailings dam by placing future mine tailings inside the waste rock dump - an advantageous design which is commonly adopted in Australia.
Known locally as an Integrated Waste Landform, the design minimises land disturbance by storing the tailings inside a rock barrier, increasing the stability of the overall tailings storage facility, substantially saving on dam wall construction and easing future rehabilitation, according to AVZ.
The company has also commenced a second phase of hydrogeological field work to assess the impact of deepening the Roche Dure pit on the water table and updating the hydrological model to be included in the Manono Environmental and Social Impact Assessment report.
AVZ looks to be ticking all the boxes as it pushes on toward a final investment decision to mine lithium in Africa.
Is your ASX listed company doing something interesting? Contact: matt.birney@businessnews.com.au
