Bayan Mining Launches First Reverse Circulation Drilling at Desert Star Rare Earth Project in California

Desert Star Maiden Drilling Program Initiates First Subsurface Testing of Rare Earth Targets

On 4 June 2026, Bayan Mining announced the start of its maiden reverse circulation drilling program at the Desert Star Rare Earth Project. This marks the company’s first subsurface test of priority targets developed through integrated geological mapping, geophysical surveys, and high-grade surface geochemistry. The program involves up to 1,000 metres of RC drilling aimed at assessing the scale, continuity, and geometry of rare earth element mineralisation at depth. The drilling targets down-dip extensions of mapped structures where previous surface sampling returned elevated rare earth values, including rock chip samples with up to 66,810 ppm TREO (6.68% TREO) and heavy mineral concentrate samples reaching 91,092 ppm TREO (9.11% TREO).

The main goal of the Maiden Drill Program is to define the geometry, continuity, and alteration characteristics of rare earth element-bearing zones beneath the surface. Drilling also evaluates the potential link between surface rare earth anomalies and a low-susceptibility, high-density geophysical body identified via detailed 3D geophysical modelling, which is interpreted to start around 100 metres depth and intensify near 300 metres. RC samples are collected regularly and logged by the geological team, with representative chips retained for interpretation. Selected samples undergo analysis following Bayan’s quality assurance and control protocols.

Monazite-Hosted Rare Earth Mineralisation Validated by Petrography and XRD Analysis

Mineralogy and petrographic results released on 9 April 2026 confirmed monazite-hosted rare earth element mineralisation across high-grade samples from Desert Star. XRD analysis identified a monazite-bearing rare earth element assemblage in all three samples, consistent with a light rare earth element-dominant system. Surface sample 19583 contained 6.54 wt% monazite, 3.06 wt% allanite, 4.10 wt% fluorapatite, and 0.15 wt% xenotime. Petrographic examination by Spectrum Petrography described altered diorite hosting monazite, xenotime, allanite, zircon, and apatite, providing strong evidence of hard-rock, phosphate-rich to mixed phosphate-silicate rare earth mineralisation at Desert Star.

Heavy mineral concentrate sample 19597 showed the highest monazite content at 14.84 wt%, along with 3.36 wt% fluorapatite and 0.43 wt% xenotime. Sample 19598 contained 4.10 wt% monazite and was dominated by almandine at 43.47 wt%, indicating mineralogical variability along the sampled corridor. Bayan noted these heavy mineral concentrate samples may represent residual or colluvial concentrations from nearby hard-rock sources rather than direct analogues of exposed lithology. The confirmed presence of monazite across multiple samples supports the geological interpretation of a phosphate-rich, intrusive-related rare earth system at Desert Star.

Site Preparation and Contractor Engagement Ensure Safe, Compliant Drilling Operations

On 7 May 2026, Bayan Mining appointed two specialist contractors to support the Maiden Drill Program. Kyle Mountain Fire LLC, trading as WaterPros, manages field water logistics, including sourcing, transport, and on-site supply for drilling. MP Environmental Services Inc. handles earthworks, drill site preparation, cleanup, and close-out activities. Both contractors conducted detailed site inspections with Bayan’s project team to confirm scope, access, pad locations, and health, safety, and environmental requirements. This coordination aimed to minimize startup risks and ensure efficient, safe drilling operations.

MP Environmental completed all site preparation at Desert Star on 4 June 2026, meeting Bureau of Land Management operational standards. Work included drill pad construction, sump excavation, and access road upgrades to enable safe, efficient access to drill sites. The company confirmed all infrastructure was ready to support the Maiden Drill Program, allowing drilling to proceed on schedule and in compliance with regulatory requirements. This preparation was essential for smooth, safe drilling execution.

Strategic Collaboration with US Critical Materials Corp to Evaluate Rare Earth Beneficiation Technologies

Bayan Mining signed a non-binding Memorandum of Understanding with US Critical Materials Corp to assess beneficiation technologies developed by the Colorado School of Mines on bastnaesite- and ancylite-hosted rare earth mineralisation from the Sheep Creek Project in Montana. This partnership establishes a framework for metallurgical testing and evaluation of future commercialisation opportunities, advancing the company’s rare earth processing capabilities. The non-binding agreement underscores Bayan’s commitment to progressing both exploration and downstream processing aspects of its rare earth projects.

This collaboration aligns with Bayan’s broader strategy to develop processing technology alongside exploration and project development. Leveraging US Critical Materials Corp and Colorado School of Mines expertise, the company aims to evaluate beneficiation approaches for its mineralisation styles. The Sheep Creek Project hosts bastnaesite and ancylite mineralisation, distinct from Desert Star’s monazite system, providing exposure to diverse deposit types and processing options. This evaluation may support future commercialisation and enhance recovery understanding across Bayan’s portfolio.

New Geophysical Data Refines Bayan Springs North Exploration Targets

Bayan Mining reported that interpretation of new USGS Earth MRI airborne magnetic and radiometric data identified two priority exploration targets at Bayan Springs North. These targets are supported by coincident geophysical signatures and anomalous pathfinder geochemistry, offering a clear framework for upcoming sampling and target refinement. The company’s geophysical analysis has effectively translated new survey data into actionable exploration priorities, demonstrating disciplined, systematic target generation.

The integration of airborne magnetic, radiometric, and geochemical data enhances understanding of Bayan Springs North’s prospectivity and guides exploration focus. Defining two priority targets with multiple supporting data layers reduces exploration risk by concentrating efforts where evidence converges. This data-driven targeting exemplifies systematic rare earth exploration and positions Bayan to efficiently advance its California project portfolio.

Strong Cash Position Supports Exploration Strategy Through June 2026

As of 30 June 2026, Bayan Mining reported A$1.44 million in cash and cash equivalents, providing financial backing for ongoing exploration and advancement of rare earth processing technology initiatives. This liquidity supported the initiation of the Maiden Drill Program at Desert Star and other activities across the company’s portfolio during the quarter. Effective cash management enabled Bayan to meet key milestones including site preparation, drilling commencement, and contractor engagement without external capital constraints.

The cash balance reflects prioritization of high-confidence targets and foundational infrastructure development. With A$1.44 million available at quarter-end, Bayan maintains sufficient liquidity to continue drilling, sample analysis, and project development across its California and Montana assets. Investors should monitor cash burn as drilling progresses and follow-up work advances at identified targets.

Diverse Rare Earth Exploration Portfolio Across California and Montana

Bayan Mining and Minerals Limited’s rare earth exploration portfolio includes projects in California and Montana. The Desert Star Rare Earth Project and Desert Star North Projects in California are the company’s primary focus, with Desert Star wholly owned by Bayan. These projects feature monazite-bearing, light rare earth element-dominant mineralisation in a phosphate-rich, intrusive-related geological environment. Comprehensive Phase 1 and Phase 2 surface sampling at Desert Star generated high-grade samples that justified progression to drilling during the June 2026 quarter.

The Sheep Creek Project in Montana represents a secondary asset, hosting bastnaesite- and ancylite-hosted rare earth mineralisation, contrasting with Desert Star’s monazite system. This geographic and mineralogical diversification provides exposure to multiple deposit types and prospective terranes. Bayan’s exploration strategy integrates geological, geochemical, mineralogical, petrographic, and 3D geophysical modelling techniques to systematically define and evaluate targets. Maintaining a portfolio spanning different projects and mineralisation styles maximizes opportunities within the rare earth sector.

Rare Earth Market Dynamics and Strategic Positioning in US Critical Minerals Supply Chain

Rare earth elements are essential for renewable energy, defense, electronics, and advanced manufacturing worldwide. The United States classifies rare earths as critical minerals, fostering government policies and investments supportive of domestic exploration and development. Bayan’s focus on California and Montana projects positions it to participate in North American supply chains and benefit from domestic sourcing preferences and policy incentives. The Desert Star drilling commencement amid heightened strategic emphasis on rare earth supply chain resilience may accelerate project development and commercialization prospects.

Bayan’s collaboration with US Critical Materials Corp and Colorado School of Mines on beneficiation technologies highlights its integrated approach from exploration to processing. Securing efficient processing pathways is as vital as resource identification, and Bayan’s early-stage beneficiation evaluation positions it to address both exploration and downstream development. The current market context, characterized by supply chain concerns and supportive policies in North America, creates a favorable environment for companies expanding rare earth production and processing capabilities.

Exploration Risk Management and Regulatory Compliance in Desert Star Drilling

Bayan Mining’s execution of the Maiden Drill Program at Desert Star demonstrates thorough exploration risk management through specialist contractor engagement, comprehensive site preparation, and strict adherence to Bureau of Land Management regulations. The appointments of WaterPros and MP Environmental Services mitigated operational risks related to water logistics and site infrastructure, facilitating efficient drilling. Early alignment on scope, access, and health, safety, and environmental standards minimized startup risks and promoted controlled operations, reflecting management’s commitment to discipline and compliance.

Exploration in California requires navigating complex environmental and regulatory frameworks, including BLM authorizations and state permits. Bayan’s focus on regulatory compliance during site preparation and contractor selection indicates a structured approach to permitting. Successful drilling depends on geological results and flawless operational and regulatory performance. Potential operational delays, regulatory challenges, or environmental issues during drilling could impact timelines and costs. Investors should closely monitor drilling progress and compliance outcomes.