Cobra Resources Completes Sonic Core Drilling at Boland REE Prospect

19 February 2024 15:27

Cobra Resources PLC (LSE:COBR) has completed sonic core drilling at the Boland Rare Earth Element (REE) Prospect, situated within its Wudinna Project in South Australia, unveiling positive preliminary geological observations that suggest the Boland Discovery possesses the necessary characteristics to serve as a cost-effective, environmentally friendly source of magnet REEs.

Cobra’s Boland Objectives

Earlier this month, the Company initiated drilling after to confirming ionic REE recoveries in September of last year.

The sonic core drilling program, consisting of five holes, was designed to assess the scale, grade concentration, and in situ recovery (ISR) potential of the discovery.

Following the completion of drilling, the holes were cased and screened using slotted PVC screens, strategically positioned at a depth corresponding to Zone 3 mineralisation.


Figure 1: Installed wells, associated hole numbers and location of Aircore hole CBAC0164

The preliminary observations post-program were exceedingly encouraging and positive across all outlined objectives. The Wudinna Project continues to uphold its potential as a pioneering rare earth development endeavour through ISR mining.

Preliminary Observations

Cobra has released several of the observations made during the drilling program:

  • High grade concentrations of REEs occur within permeable zones.
    • Consistently high XRF grades coincide with the interval that delivered exceptional metallurgical recoveries (47% Pr, 60% Nd, 67% Dy, 79% Tb at pH3).
    • Casing and screens have been set to test this horizon
  • Multiple zones of mineralisation:
    • XRF downhole analyses supports grade concentration within three zones (Zones 1-3) where mineralisation is concentrated at permeable boundaries
    • The three zones have produced consistent high XRF spot readings (>2,000 ppm) (Ce+La+Nd+Pr+Y) contacting permeable sands across all five cores
    • Zone 1: elevated XRF REE grades either side of a medium grained, reduced sand unit from 16-17 metres
    • Zone 2: elevated XRF REE grades within smectite clays that contain fine sand interbeds from 21-23 metres
    • Zone 3: reduced basal unit with high sand content in direct contact with underlying saprolite. Upward coarsening unit 26-28 metres

Figure 2: CBS0001 – mineralised Zone 3 core photographs with corresponding downhole XRF readings (Ce+La+Pr+Nd+Y) compared to the downhole 3m composite grades reported for Aircore hole CBAC0164 (drilled C~20m east of CBS0001)

Scale and ISR Potential

During the drilling campaign, the Project’s scale potential was evaluated, revealing mineralised sequences within regionally extensive geological units. This discovery significantly enhances the potential REE footprint.

Cobra’s tenure spans approximately 2,000 square kilometres of promising palaeochannel geology, highlighting the expansive scale potential of the Wudinna Project.

The drill campaign successfully assessed the potential for ISR mining, with core samples collected indicating the presence of geological conditions conducive to ISR mining across the tenure.

Notably, the collected core samples showed mineralised intervals containing moderate sand quantities or contacting permeable sands. These intervals exhibit excellent lateral connectivity within a confined aquifer, further supporting the ISR potential.

The Next Steps

Building on these promising findings, Cobra is poised to advance the Project towards its development objectives. The PVC screens, strategically placed during the drilling campaign to align with Zone 3 mineralisation, will serve as conduits for hydrology studies slated to commence in the upcoming weeks, thereby laying the groundwork for a future pilot study.

Cobra has additionally dispatched select core samples to the Nuclear Science and Technology Organisation in Australia for column ISR testing, with results anticipated within several weeks.

During the drilling, the collected core was sampled and halved, with a portion sent fpr further testing to evaluate grade variability across different horizons, guiding resource drilling parameters.

Permeability testing is currently underway to delineate the production potential of the site.

Company Comments

Cobra Resources CEO Rupert Verco commented on the promising results.

“We are truly excited about what this drilling is defining. The Boland prospect presents as a world first for palaeochannel hosted ionic REEs via in situ recovery mining,” he said.

“Initial indications for grade concentration are positive and geological conditions reinforce our belief that recovery by ISR will be highly successful.”

“Cobra is taking the right steps to demonstrate that the Boland ionic rare earths discovery has the potential to change the global supply of magnet rare earths through low disturbance, low cost in situ recovery mining at significant scale.”

“We are grateful to Star Drilling, our contractors, staff, and stakeholders who have done an exceptional job to ensure the programme has been safe and seamless.”

“We eagerly await the follow-up assays and studies that we believe will establish this project as a worldclass rare earths project. We could not have asked for a better start to 2024.”

COBR’s London Stock Exchange-listed share price is currently trading at 0.93 pence (3.30pm UTC+ 8 hours).

The Market Bull Logo


Join our mailing list to receive the latest stock market news.

You have Successfully Subscribed!

Share This