AVZ Minerals (ASX: AVZ) has re-started geological diamond core resource drilling at its Manono lithium-tin project in the Democratic Republic of Congo after the country lifted travel restrictions in mid-September.
Drilling is taking place at the Roche Dure pit floor with a planned total 10 new geological holes for 1,700m. It is in an area previously inaccessible because of water, and will continue over the next four weeks.
The program aims to upgrade some inferred resources to indicated status.
Also, new ore reserves are to be generated from an updated mine design.
Manono is 65% owned by AVZ, with the DRC Government holding a 25% stake and 10% being held by another Congolese entity.
AVZ revealed last month it was increasing its ownership to 75% by buying out the Congolese entity’s 10% for US$15.5 million.
Manono is expected to have a development bill of US$545 million (A$750 million).
Waste rock may be changed to mineable ore
Previous drilling at Roche Dure defined more than 7Mt of potential ore at an average grade of 1.65% lithium oxide.
But the material immediately beneath the then water-filled open pit could not be accessed physically and therefore remained in the inferred category.
This meant that the pit floor rock could not be considered as mineable ore in the existing mine plan.
AVZ says it expects some of the pegmatite may be upgraded to either indicated resource or probable reserve categories.
“The updated geological resource is not expected to increase overall resource tonnes but the combined indicated and measured resource tonnage is expected to increase,” the company said.
Assay results are expected next month provided drilling can be finished by the end of this month.
However, some of the rock previously classified as waste may then be reported as mineable ore.
Improved tailings storage using rock dump
Meanwhile, AVZ has confirmed a site for tailings storage.
AVZ has made a technical decision to place future mine tailings inside the waste rock dump to the west of the Roche Dure open pit.
This design, commonly used in Australia, minimises land disturbance and means a substantially increased savings on dam wall construction and improves ease of future rehabilitation.
Last month AVZ was accepted as a member of the European Battery Alliance, an organisation launched by the European Commission. The commission has recently added lithium to the European Union’s critical raw materials list.
Battery capacity in Europe is expected to rise from 100 gigawatt hours in 2022 to more than 500GWh by 2029.
Europe’s share of global battery production is forecast to increase from 6% now to 16% by 2030.