Andrada Mining has updated the mineral resource estimate for the Uis Tin Mine announced on 6 February 2023 and incorporated analytical results from the final 16 drill holes of the 2022 programme, as well as a volume depletion surface as of 30 August 2024.
The update shows an increase in average lithium grade and volumes of the measured and indicated resource classifications.
It also shows an increase of the average lithium grade to 0.79% Li2O from 0.73% Li2O declared in 2023.
The contained lithium oxide increased from 587,000 tons to 610,000 tons, while the measured resource tonnage increased by 30% to about 27.3 million tons.
The indicated resource tonnage increased by 2% to 17.5 mt, but the mineral resource estimate total tonnage decreased from 81 mt in 2023 to 77.5 mt due to depletion from ongoing mining.
The 145 historical ISCOR drill holes, comprised of eight diamond, 137 reverse circulation, 77 validation, 48 diamond and 29 reverse circulation holes drilled by Andrada between 2018 and 2023, informed the mineral resource estimate.
The Andrada drill holes were completed on a nominal grid spacing of 60 metres by 60 metres, with wider spacing of up to 80 metres by 200 metres for the deeper portions.
Most holes were drilled vertically, but selected shallower holes were inclined at angles up to -70° southeast to obtain intersections more perpendicular to the dipping pegmatite.
The updated mineral resource estimate is reported by the JORC Code (2012) and identifies 77.51 Mt of mineralised pegmatite with an average grade of 0.79% Li2O, 0.15% Sn, and 82 ppm Ta.
This mineral resource estimate includes 27.33 mt at an average grade of 0.82% Li2O, 0.15% Sn, and 90 ppm Ta for the near-surface measured category, 17.50 mt at an average grade of 0.79% Li2O, 0.15% Sn, and 86 ppm Ta for the indicated category, and 32.68 mt with an average grade of 0.76% Li2O, 0.16% Sn, and 73 ppm Ta for the inferred category.
The contained lithium is also stated in the lithium carbonate equivalent, the metal converted to lithium carbonate by a factor of 5.323.
Andrada Mining CEO Anthony Viljoen said this updated resource estimate is another positive step toward becoming a premiere African producer of tin, lithium, and tantalum.
“Critically, this updated resource also allows us to quantify better the potential lithium concentrate credits we can generate alongside our tin production, optimising the overall project economics,” Viljoen said.
He added that the updated mineral resource estimate further enhances the project economics of the Uis mine operations and will enable the determination of a lithium mineral reserve.