ASX-listed Ionic Rare Earths has received assays from the Phase 3 rotary air blast (RAB) exploration drill programme at its 51%-owned Makuutu project in Uganda, with these indicating positive results.

Clay and saprolite mineralisation intersections above the cut-off grade of 200 parts per million total rare earth oxide less cerium oxide, consistent with the current mineral resource estimate (MRE) cut-off, have been achieved in many target areas at notable intervals.

In a positive development for the project, rare earth element- (REE-) bearing clay mineralisation has been intersected in-between previously targeted areas that indicate a laterite hardcap is present at surface, the company notes.

The drilling has shown that the hardcap is buried by over 1 m of soil in some areas.

These results indicate new areas for follow-up exploration that were previously not tested.

Mineralisation in the regolith potentially derived from, and underlain by, rocks outside the mineralised basin has also been intersected in the RAB drilling.

The company will progress a selection of these samples through salt desorption testwork to confirm the proportion of ionic adsorbed rare earth content prior to confirming a plan for further drilling these targets.

“The Phase 3 RAB assay results confirm this significantly successful exploration campaign. They confirm the massive potential of EL00147, having identified immediate extensions to the resource estimate beyond previous radiometric targeting, and additionally, indicate potential extension of ionic adsorption clay (IAC) mineralisation outside of the basin which was thought to confine the IAC mineralisation.

"We will now progress initial salt desorption testwork to confirm the metallurgical characteristics of these new mineralisation areas identified, given that some of the mineralisation appears to be derived directly from granitic rocks, therefore it is possibly more consistent with those IAC deposits of southern China.

"The Phase 3 drill assays clearly confirm the significance of Makuutu as a world class and expanding IAC deposit. The project scale expected will substantially increase in the future, with these new assays inferring considerable upside at Makuutu, beyond initial estimations. Simply put, there appears to be much more rare earth elements-bearing clay at Makuutu than we had initially expected,” MD Tim Harrison says.