Magnum Mining’s initial 24 auger holes at Piracanjuba North all intersected near-surface rare earth mineralisation, showing promising grades and high desorption rates that suggest efficient extraction potential under mild conditions.
- All first 24 holes report near-surface REE mineralisation
- Desorption rates up to 65% TREO and 82% MREO under mild conditions
- High-value magnet rare earths TbDy and SEG+Y show strong leach response
- Drilling supports 85km² geophysical anomaly validation
- Exploration Target and JORC Resource expected by September and November
Consistent Rare Earth Mineralisation Across Initial Drilling
Magnum Mining and Exploration Limited (ASX:MGU) has reported that its first 24 auger holes at the PN-04 area within the Piracanjuba North target have all intersected near-surface rare earth element (REE) mineralisation. This early batch from the ongoing 810-hole, approximately 10,000-metre drilling campaign confirms the continuity of mineralisation over a 4km² area, validating the broader 85km² geophysical anomaly that the company is targeting in Goiás, Brazil.
The reported total rare earth oxide (TREO) grades are notable, with intervals such as 2 metres at 651ppm TREO and 188ppm medium rare earth oxide (MREO) from 8 metres depth, alongside others reaching over 1,000ppm TREO. These grades are complemented by desorption rates; an indicator of how readily the rare earths can be extracted under mild conditions; reaching as high as 65% for TREO and 82% for MREO, measured using ammonium sulphate at pH 4.
Desorption Highlights Strategic Rare Earth Value
Desorption is a critical metric for ionic adsorption clay (IAC) rare earth systems, as it indicates the potential for efficient leaching and recovery. Magnum’s results show particularly strong desorption in key magnet rare earths such as terbium and dysprosium (TbDy), with rates up to 66%, and the combined medium and heavy rare earth elements plus yttrium (SEG+Y) reaching 72%. These elements are highly sought after for their applications in permanent magnets, essential for electric vehicles and renewable energy technologies.
Managing Director Antonio Vitor Junior emphasised the significance of these findings, noting that the combination of consistent mineralisation and exceptional desorption characteristics supports the potential for a world-class IAC REE system. The results differentiate Piracanjuba from deposits dominated by lower-value light rare earths, highlighting its medium and heavy rare earth content as a key value driver.
Drilling Progress and Resource Development Timeline
The current drilling program is designed to systematically test the continuity and scale of mineralisation with a 200m x 200m grid over priority targets, while a broader 1,000m x 1,000m grid explores the wider geophysical anomaly. Magnum plans to report assay and desorption results in batches as the campaign advances.
The company remains on track to deliver an Exploration Target by September 2026 and a JORC Mineral Resource Estimate by November, subject to ongoing results. These milestones are critical steps towards assessing the economic viability of the deposit, alongside planned metallurgical optimisation to improve recovery rates beyond the initial screening conditions.
Early-Stage Results Support Exploration Vectoring
While the data are encouraging, Magnum cautions that the reported intervals are apparent down-hole lengths from vertical auger drilling, and true widths and lateral continuity have yet to be confirmed. The desorption figures are preliminary screening values and not final metallurgical recoveries. Further drilling, mineralogical studies, and detailed metallurgical testwork will be essential to refine the resource model and processing approach.
The Piracanjuba North project lies within the Azimuth 125 district, a region with classic IAC-style REE potential. The company’s systematic approach focuses on assessing desorption quality, repeatability, domain definition, and optimised metallurgy to advance the project through exploration and towards development.
Bottom Line?
Magnum’s consistent early results at Piracanjuba North reinforce the prospect of a large-scale, high-value ionic clay rare earth system, but critical follow-up drilling and metallurgical work will determine its economic potential.
Questions in the middle?
- How will metallurgical optimisation improve recovery rates beyond initial desorption screening?
- Can the lateral continuity and true widths of mineralisation be confirmed with ongoing drilling?
- What impact will medium and heavy rare earth prices have on the project's economic viability?