Dual-listed Pensana Rare Earths has upgraded the measured, indicated and inferred mineral resource estimate of its Longonjo project, in Angola, to 313-million tonnes at 1.43% total rare earth oxides (REO) including 0.32% neodymium and praseodymium (NdPr) for over 4.4-million tonnes of REO, including 990 000 t of NdPr.
The upgraded estimate contains more than 2.3 times the previous estimate of the measured and indicated resources used in the prefeasibility study (PFS) and has increased the proportion of the resources reported in the measured and indicated categories from 31% to 68%.
It has also increased the overall contained NdPr by 35%.
A number of previously announced drill holes in fresh rock mineralisation immediately below the weathered zone have reported continuous mineralisation to a depth of 80 m, which Pensana says remains open.
Further drilling is planned in this area, which will form the basis for future mineral resource estimation.
The upgraded resource estimate is being incorporated into the technical studies currently underway and is expected to support an extended mine life on completion of additional workstreams of the bankable feasibility study (BFS).
Executive director Dave Hammond says the “substantial upgrade” will underpin the BFS, which the company expects will lead to a significantly extended mine life beyond the nine years defined in the PFS published in 2019.
“We have only just begun to explore the fresh rock mineralisation which lies immediately beneath the weathered zone and metallurgical test work is currently under way on this material to confirm the optimum process route to treat this second style of mineralisation, which if successful, could add significantly to the scale of the project.”