Exceptional Gold Recovery Boosts Rox Resources’ Youanmi Gold Project

Youanmi's Golden Promise: High Recovery Rates Boost Project Potential

Rox Resources Limited (ASX: RXL) has announced significant metallurgical test results from its Youanmi Gold Project, revealing gold recovery rates that exceed expectations and potentially enhancing the economics of the project.

Outstanding Recovery Results Strengthen Development Case

Recent metallurgical testing at the Youanmi Gold Project in Western Australia's Mid West region has delivered exceptional results, with 91.6% gold recovery to concentrate confirmed during bulk flotation tests. The tests also achieved a remarkable 98.3% sulphur recovery to concentrate with a corresponding concentrate grade of 49.9g/t gold.

These findings represent a critical milestone for Rox Resources as it advances toward completion of its Definitive Feasibility Study (DFS), expected in November 2025.

Further enhancing the positive outlook, additional gold recovery of 36%-62% was achieved through cyanide leaching of the flotation tailings, suggesting potential for even higher overall gold recoveries.

"The results received so far from the metallurgical test work program reinforce what we already knew about the highly prospective nature of our Youanmi Gold Project," said Rox Resources Managing Director & CEO Phill Wilding. "It was exciting to see the high gold recoveries returned were better than the PFS estimates."

The Albion Process: A Game-Changer for Semi-Refractory Gold

A key component of Rox's ongoing metallurgical program is testing of the Albion Process™, an atmospheric oxidative leaching technique specifically designed for treating semi-refractory gold ores like those found at Youanmi.

The Albion Process™ could provide several significant advantages:

• Improved overall gold recovery
• Reduced reagent consumption
• Lower power requirements
• Decreased operating and capital costs

This two-stage process begins with ultrafine grinding of the flotation concentrate using an IsaMill™ to a grind size P80 of 8-20 µm, followed by oxidative leaching in the OxiLeach™ Reactor under specific conditions:

• Atmospheric pressure
• pH of 4-5
• Elevated temperature of 95°C
• Residence time up to 72 hours

The technology is particularly well-suited to Youanmi's semi-refractory gold concentrates, which don't require more than 90% sulphur oxidation to achieve acceptable gold recoveries.

Understanding Youanmi's Gold Mineralogy

The metallurgical testing has provided valuable insights into the nature of gold mineralisation at Youanmi. Petrographic analysis revealed three distinct types of gold occurrence:

1. Refractory ore – Very fine-grained gold particles enclosed within pyrite grains
2. Semi-refractory ore – Gold within pyrite grains that lie in and/or along fractures and cavities
3. Free-milling ore – Gold in open cavities, attached to external margins of sulphide grains, or occurring within silicate matrix

Mineralogy testing indicates that 75-80% of gold at Youanmi is either free-milling or semi-refractory and primarily associated with pyrite. The remaining gold (up to 25%) is locked in solid solution in arsenopyrite, which cannot be recovered through conventional cyanide leaching or ultrafine grinding—highlighting the potential value of the Albion Process™.

What Is Semi-Refractory Gold?

Semi-refractory gold deposits represent a classification between free-milling gold (easily extractable by conventional cyanidation) and fully refractory gold (highly resistant to standard recovery methods).

In semi-refractory ore bodies:

• Gold particles are partially encapsulated within sulphide minerals (primarily pyrite and arsenopyrite)
• Standard cyanidation typically yields suboptimal recovery rates (30-80%)
• The ore requires additional processing to liberate gold trapped within sulphide structures
• Recovery methods typically involve partial oxidation of sulphide minerals through various techniques

At Youanmi, the semi-refractory nature of the gold is demonstrated by:

• Microscopic gold grains occurring along fractures and cavities within pyrite crystals
• Gold in solid solution within arsenopyrite (at concentrations of 242-447 ppm)
• Variable recovery rates from different ore domains

The Albion Process™ is well-suited for semi-refractory gold as it provides controlled oxidation of sulphide minerals, liberating the encapsulated gold without the high capital and operating costs associated with pressure oxidation or roasting methods used for fully refractory ores.

Comprehensive Sampling Across Multiple Lithologies

The metallurgical test work utilised samples that represent over 95% of the planned plant feed identified in the Pre-Feasibility Study:

• High iron (Fe) tholeiite (basalt) – ~25% of plant feed
• High magnesium (Mg) tholeiite (basalt) – ~60% of plant feed
• Banded Iron Formation (BIF) – <5% of plant feed
• Granite – <10% of plant feed

This comprehensive approach ensures that the test results accurately reflect the diverse mineralisation at Youanmi and provides confidence in the projected recovery rates.

On Track for Production with Clear Development Timeline

The metallurgical test work results will be incorporated into Rox's Definitive Feasibility Study, with the company making steady progress on its pathway to production:

• Drilling completed on time and within budget
• Refurbishment of evaporation ponds complete
• Tenders awarded for major DFS work streams
• Dewatering pipe/pump installation underway
• Comminution/flotation metallurgical test work complete

With these latest results, Rox Resources is positioned to release its DFS in November 2025, representing a major step toward bringing the historic Youanmi Gold Project back into production.

Why Investors Should Take Note of Rox Resources

The latest metallurgical results underscore the compelling investment case for Rox Resources:

1. Resource Strength: Youanmi boasts a Total Mineral Resource of 2.3Moz of contained gold with significant expansion potential.

2. Technical De-risking: Each phase of testing continues to validate and enhance the project's technical fundamentals.

3. Historical Precedent: Youanmi was previously a high-grade gold mine that produced approximately 667,000oz of gold at an impressive grade of 5.47 g/t Au.

4. Infrastructure Advantage: The project is classified as a disturbed site with existing mining leases and infrastructure, significantly reducing development costs and timelines.

5. Near-term Catalysts: With the DFS expected in November 2025, investors can anticipate a steady stream of news flow as Rox Resources continues to advance the project toward a production decision.

For gold investors seeking exposure to advanced development projects with proven metallurgy and clear paths to production, Rox Resources' Youanmi Gold Project offers a compelling opportunity backed by increasingly positive technical results.

Ready to Unlock Youanmi's Golden Potential?

Discover how Rox Resources is positioning the Youanmi Gold Project for success with exceptional recovery rates and innovative processing techniques. To learn more about this compelling investment opportunity and stay updated on the company's progress towards its November 2025 DFS completion, visit Rox Resources' website today.