Octava Minerals Defines Massive Byro Exploration Target with Strong Bioleaching Potential

• Byro exploration target between 4.9 and 7.4 billion tonnes
• Grades of TREO, lithium oxide, and vanadium oxide confirmed
• Bioleaching tests achieved 70-80% recoveries within 21 days
• Aircore drilling delineated 11km by 10km mineralised area
• Next steps include resource definition and heap bioleaching trials

Byro Project Reveals Giant Critical Minerals Target

Octava Minerals Ltd (ASX:OCT) has unveiled a conceptual exploration target of between 4.9 and 7.4 billion tonnes of mineralised black shale at its 100% owned Byro Critical Minerals Project in Western Australia. This vast tonnage hosts significant concentrations of rare earth oxides (TREO), lithium oxide (Li2O), and vanadium oxide (V2O5), positioning Byro as a potentially major source of these strategic commodities.

The exploration target was derived from a recent aircore drilling campaign comprising 16 holes totaling 870 metres, which delineated an 11 by 10 kilometre area of mineralisation to a depth of 50 metres. Grades range from 207 to 431 ppm TREO, 159 to 331 ppm Li2O, and 173 to 359 ppm V2O5, consistent with earlier samples used in bioleaching testwork.

Bioleaching Success Points to Sustainable Processing

Octava’s Managing Director Bevan Wakelam highlighted the importance of the bioleaching results, which demonstrated 70-80% recoveries of critical minerals within a 21-day leaching period. Conducted by independent experts CSIRO and BiotaTec, the bioleaching process operates at lower temperatures and uses microorganisms to extract metals, offering potential reductions in energy consumption, chemical use, and overall operating costs.

This sustainable extraction method could be a game-changer for large, lower-grade deposits like Byro. The company is now focused on scaling up bioleaching testwork, including laboratory and continuous column trials to simulate heap leaching conditions, which if successful, would further reduce capital and operational expenditures.

Geological Setting and Historical Context

Byro lies within the Permo-Carboniferous Byro Sub-basin of the Carnarvon Basin, a 100 by 150 kilometre sedimentary basin known for its black shale formations. The key target zone is the Coyrie Formation, a 200-400 metre thick sequence of interbedded black shale, siltstone, and sandstone.

Historical exploration, including government soil sampling and drilling by Pioneer Resources, identified extensive rare earth and lithium anomalies over a 40-kilometre strike length. Octava’s recent drilling has confirmed and extended these mineralised zones, providing the foundation for the current exploration target.

Next Steps Toward Resource Definition and Pilot Trials

With a conceptual target now in place, Octava plans further drilling to progress towards a maiden mineral resource estimate. This will refine the tonnage and grade model and support feasibility studies.

Simultaneously, metallurgical programs will evaluate the feasibility of heap bioleaching at scale, aiming to establish optimal operating parameters and assess technical risks. Success here would mark a significant step toward commercialising a low-impact, cost-effective extraction process for Byro’s critical minerals.

Strategically, the project benefits from existing infrastructure, including proximity to the Geraldton port and access to power from the Northwest gas pipeline, alongside a native title agreement with the Wajarri Yamaji Aboriginal Corporation, smoothing the path for development.

Bottom Line?

Octava's Byro project stands out with its immense scale and promising bioleaching recoveries, but the path from exploration target to resource and commercial viability hinges on upcoming drilling and heap leaching trials.

Questions in the middle?

• Can Octava scale bioleaching from laboratory to industrial heap trials effectively?
• How will the evolving grades and tonnage from further drilling impact project economics?
• What partnerships or funding strategies will support the next development phases?