Resolution Minerals Ltd reports significant 3D modelling results at its Antimony Ridge Mine Project in Idaho, revealing over 100 high-grade antimony-silver veins over a large area. The project has secured FAST-41 status to accelerate permitting and development.
- 3D modelling identifies 30 vein swarms over 1000m x 700m area with 250m vertical extent
- Historical mining yielded antimony grades consistently above 30% and silver up to 1,420 g/t
- Project selected for US FAST-41 permitting to expedite development
- Plans include up to 250 drill holes and bulk sampling pending Plan of Operations approval
- Metallurgical test results from high-grade stibnite samples are forthcoming
3D Modelling Highlights Large-Scale Antimony-Silver Mineralisation
Resolution Minerals Ltd (ASX:RML; OTCQB: RLMLF) has released detailed results from three-dimensional modelling of its Antimony Ridge Mine Project in Idaho, USA. The modelling reveals more than 100 high-grade antimony (Sb) and silver (Ag) bearing veins arranged in 30 discrete vein swarms, fault breccias, and stockworks. These mineralised structures extend over an area approximately 1,000 metres long by 700 metres wide, with a vertical range of 250 metres, indicating significant size and expanding scale potential for the deposit.
The veins are exposed in historical open pits and trenches, with some veins exceeding 100 metres in strike length and true thicknesses up to 1 metre. This extensive network of stacked "en echelon" veins forms a broad corridor of mineralisation, which remains open-ended in all directions, suggesting further exploration upside.
Historical Mining and High-Grade Assays Support Project Potential
Antimony Ridge has a history of mining by the US Government during World War I, World War II, and the Korean War, serving as a key domestic source of antimony for military applications. During World War II, the district including the adjacent Stibnite mine produced over 90% of US antimony supply, underscoring the strategic importance of the region.
Recent rock chip sampling and large-volume bulk samples from the prior open pits have confirmed exceptionally high grades, with antimony consistently above 30% and reaching up to 48.7% Sb. Silver grades range from 250 grams per tonne to a peak of 1,420 grams per tonne, with gold also present at lower levels. Surrounding the high-grade veins is a broader halo of lower-grade mineralisation, with antimony grades between 0.5% and 2%, and silver between 5 and 60 g/t, extending the footprint of the mineralised system.
FAST-41 Permitting Status to Accelerate Development
Antimony Ridge was recently selected for the US FAST-41 Transparency Coverage by the US Permitting Council, a designation intended to streamline and accelerate permitting timelines for critical mineral projects. This status reflects the project's strategic importance as a potential domestic source of antimony, a metal critical for defence, energy, and industrial applications.
Resolution plans to undertake a substantial bulk sampling program and an extensive drilling campaign of up to 250 drill holes, pending approval of a Plan of Operations. These activities aim to better define the resource scale and support future development decisions.
This permitting progress aligns with Resolution’s broader Horse Heaven Project strategy, which also includes tungsten and gold assets. The company is preparing for a major Phase 2 drilling program at its Golden Gate Project starting in May 2026, targeting gold and tungsten mineralisation, with the goal of defining a maiden Mineral Resource Estimate. The FAST-41 status supports this integrated US-focused critical minerals platform, enhancing the potential for coordinated project advancement. This follows the recent advancement of FAST-41 permitting status for Antimony Ridge that highlighted the project's strategic positioning.
Metallurgical Testing and Future Work
Preliminary metallurgical test work is underway on approximately 100 kilograms of representative high-grade stibnite material. Testing is being conducted by multiple independent laboratories across pyrometallurgical and hydrometallurgical processes to validate processing routes. An end-product of antimony trioxide is anticipated soon for pre-qualification with potential US end users, which will be critical to assess the economic viability of the deposit.
Further exploration including detailed mapping, sampling, bulk sampling, and drilling is planned to expand understanding of the vein systems and mineralisation continuity. The company confirms that exploration remains incomplete and expects to define additional mineralised zones as work progresses.
Bottom Line?
Resolution Minerals’ 3D modelling and FAST-41 permitting status position Antimony Ridge as a strategically significant project, though metallurgical results and drilling outcomes will be key to confirming its development potential.
Questions in the middle?
- How will forthcoming metallurgical test results influence processing strategies and project economics?
- What scale and grade continuity will the planned 250-hole drilling program reveal about the Antimony Ridge deposit?
- How might FAST-41 permitting accelerate timelines compared to typical US mining project approvals?