Byro

The Byro Critical Minerals Project is located on the Byro Plains of the Gascoyne Region, Western Australia, 220 km south-east of Carnarvon and 650 km north of Perth. It consists of two granted Exploration Licences – E 09/2673 and E 09/2674 – totalling 555 km2. The Byro project is prospective for critical minerals including rare earths (REE’s), lithium and base metals

The Byro Project has Native Title agreements in place. Nearby infrastructure includes accessibility to a commercial port (Geraldton) and power from the NW gas pipeline and future potential access to Western Australian government proposed green energy sites.

The target stratigraphy is the sedimentary Permian black shales and siltstones located within the Byro Sub-Basin of the Carnarvon Basin. The restricted basin is approximately 100km by 150km in size, and up to 3km in depth. Permian Black shales are known worldwide for their potential to host large, enriched poly-metallic deposits.

Previous GSWA regional soil sampling (4km by 4km sample spacing) identified extensive anomalous halos of REO & Li2O over 40km in strike length and 20km wide. The tenement area also contains five wide-spaced historic RC drillholes over a ~ 25km strike length and four historic petroleum boreholes over 5km. This historic drilling supports the continuity of the metal hosting black shale horizon at Byro.

Project location map & Byro tenements.

Biomining microorganisms (Photo by courtesy of CSIRO)

Biomining / Bioleaching of Black Shale – Potential application to the Byro Project

Biomining is the technique of extracting metals from ores and other solid materials typically using micro-organisms (i.e. bacteria, fungi or plants).

It was discovered in the mid-1900s that some microorganisms can use metals to support theirenergy needs. In addition, certain microbes excrete compounds that break down the metal containing chemical complexes in ores. As a result, they are capable of separating metals fromores, providing a soluble form of metals, which can then be isolated. Black shales are a favourablehost for biomining given their reduced nature and high sulphide content.

Bioleaching has distinct sustainability and operational advantages over traditional extraction methods:

Reduced chemical use – avoids the use of highly toxic chemicals
Energy Efficient – Bioleaching consumes up to 90% less energy than conventional production methods, operating at ambient temperatures significantly reducing the energy needed for heating and reduced CO2 footprint
Lower operating costs – simpler, cost-effective process

Examples of biomining applications include numerous copper mines in Chile, gold processing (e.g. BIOX process developed by Gold Fields1) and the polymetallic black shale Talvivaara heap leach mine in Finland.

The black shales of the Byro sub-basin are a vast accumulation of critical metals, covering 10km’s and up to 100m metres in thickness from near surface. Octava envisages a potential pathway to production for a-large-scale, low-grade deposit, which can utilise cost effective heap leaching using microbial bioleaching as the extractant.

Bioleaching Testwork Results

Biomining is project specific and a specialised science and Octava co-ordinated two parallel work streams, testing the extraction potential of the Byro Project black shale material, namely through CSIRO in Australia and BiotaTec in Europe.

Results of initial bioleaching testwork on the Byro material by both BiotaTec and CSIRO have recorded excellent extraction rates of rare earths and lithium.

Results included:

69-75% for Nd, Pr & Dy key elements used in magnet production
40 – 50% for Li, V & Terbium key elements in battery technology.

The test program used proprietary microbial cultures to extract REE’s, Li and other critical minerals from the Byro Project material. The test results also confirm that further optimisation will improve the metal recoveries and upscale the process.

Having two, independent expert groups produce excellent initial testwork on Byro material is a great outcome, indicating significant potential for a rapid heap leach operation.

Sample spoils of black shale, from historic RC drilling at the Byro Project.

Potential scheme for processing Byro Project Black Shale

In January 2024, Octava announced it had signed a binding conditional share sale agreement to purchase 100% of the shares in Byro, from the vendors (shareholders) of Byro. Byro is the registered holder of the Byro REE and Li Project, which comprises tenements E 09/2673 and E 09/2674.

Following the strong initial testwork results achieved on Byro material by BiotaTec and CSIRO, Octava will, subject to all necessary shareholder and regulatory approvals, exercise its option to acquire 100% of the Byro Critical Minerals Project.