Chilwa Minerals (ASX:CHW) has reported widespread rare earth element (REE) mineralisation in clays directly beneath its Mposa heavy mineral sands deposit at the Lake Chilwa project in southern Malawi.
Assays from 200 samples confirm total rare earth oxide (TREO) grades averaging 525 parts per million (ppm) across an 8km corridor, with 114 samples returning over 500 ppm and 17 samples exceeding 750 ppm.
Chilwa says a peak grade of 987 ppm was also recorded in hole MPOSD509.
The rare earths are hosted within basal clay intervals sitting immediately below the company’s established HMS deposit, opening up the potential for a dual-commodity mining operation.
While the clay unit extends to depths of tens of metres, the company notes it has not yet been systematically sampled.
Managing Director Cadell Buss describes these recent results as “exciting”.
“The assays have come back confirming widespread REE mineralisation — averaging 525 ppm TREO and consistently above 500 ppm across an eight-kilometre corridor,” Buss says.
“The basket is encouraging too, with the valuable magnet rare earths — neodymium, praseodymium, dysprosium and terbium — making up around a fifth of the total.”
Chilwa says heavy rare earth oxides make up about 19.6% of the total basket, with neodymium-praseodymium oxide averaging 102 ppm across all samples.
The company now intends to conduct initial metallurgical testwork at the Australian Nuclear Science and Technology Organisation (ANSTO) in Sydney to determine the proportion of recoverable rare earths in ionic-adsorbed form.
Following these results, Chilwa plans to extend deep drilling to HMS deposits on its licence, including the substantially larger Mpyupyu deposits, which cover 15km2 compared to Mposa’s 5.5km2.
Chilwa Minerals is a southern Malawi-focused critical minerals explorer advancing four concurrent programs within its Lake Chilwa licence.
Write to Paula Fabe at Mining.com.au
Images: Chilwa Minerals
