Resolution Minerals Ltd (ASX: RML; OTCQB: RLMLF) (“Resolution Minerals” or “Company”) has announced outstanding assay results from surface rockchip and soil sampling at its Antimony Ridge target. The target sits within the Horse Heaven Gold(Au)-Antimony(Sb)-Silver(Ag)-Tungsten Project, Idaho, USA.
Ultra-High-Grade Samples Strengthen Project
The Company is conducting a surface sampling program to define an Sb-Au-Ag JORC-compliant target. As part of the rockchip and soil sampling program, seven samples were taken from Antimony Ridge. Two samples were taken from ore material adjacent to an abandoned mine. The assay results of these samples are as follows:
- 730253: 49.8% antimony, 1,420g/t silver, and 3.12g/t gold
- 730255: 10.35% antimony, 68.5g/t silver, and 4.43g/t gold.
Visual mineralisation is confirmed to be stibnite (antimony sulphide mineral). The stibnite occurs in massive form, with an estimated abundance ranging from 75% to 90% in the rock specimens.
Figure 1: Location of Rockchip Sampling Sites at Antimony Ridge.
Expanding the Mineralisation Footprint
The Company recently completed a soil sampling program at Antimony Ridge. It revealed a large corridor of mineralisation, trending northeast-southwest. The Sb-Ag-Au mineralisation zone measures approximately 1,000m * 700m. Results returned up to 0.5% antimony, 0.9g/t gold, and 68g/t silver.
Craig Lindsay, the Company’s CEO of US operations, said, “We are very encouraged by the recent sampling program results from Antimony Ridge, which indicate that the mineralised target is larger than initially thought. As we expand outwards from the immediate area of the historic workings, we look to expand the target even further.”
These results significantly expand the known potential of Antimony Ridge. Importantly, the anomalies remain open in both directions, with indications of possible parallel mineralised zones. The broader corridor confirms that mineralisation is not limited to historic workings but extends well beyond previously tested areas.
Historical Work Supports Strong Potential
Past trench rockchip sampling within the Antimony Ridge area had identified strong Sb, Ag, and Au mineralisation. Previous testing included 61 rockchip samples, and more than 60% returned results greater than 1g/t gold. Peak results included 5.9g/t gold, 19% antimony, and 367g/t silver.
Figure 2: Average Au, Ag, and Sb Grades from Historic Rockchip Sampling.
The Company has also reported many significant rockchip samples from Antimony Ridge:
- 329003: 3.68g/t Au, 303g/t Ag and 2.72% Sb over 4m.
- 329014: 1.33g/t Au, 367g/t Ag and 13.75% Sb over 1m.
- 329015: 4.65g/t Au, 70.5g/t Ag and 19.15% Sb over 1m.
- 329085: 3.21g/t Au, 178g/t Ag and 0.37% Sb over 3m.
- 329089: 5.99g/t Au, 246g/t Ag and 0.71% Sb over 1m.
Bulk Sampling and Metallurgical Studies Planned
The Company plans to continue surface exploration at Antimony Ridge, including additional rockchip and soil sampling. Bulk sampling will follow to refine metallurgical understanding. The Company intends to apply for permits to conduct a Phase 1 drill program at Antimony Ridge. This will build on the strong surface results and test extensions of the mineralised system. At the same time, drilling at Golden Gate will continue, with results to be released as they become available. Resolution is also running a stream sediment sampling program across the broader Horse Heaven Project.
The Company has commenced collecting representative bulk samples from stibnite-silica vein exposures at Antimony Ridge. These will undergo preliminary metallurgical testing to understand processing options and potential product characteristics. The Company sees strong potential for direct shipping ore, given the exceptionally high antimony grades.
The Company’s Senior Strategic Advisor, Steve Promnitz, said, “High grades (of antimony) around 50% Sb are truly rare. They usually reflect crystalline antimony, potentially available for direct shipping ore as an oxide. This is because high-grade antimony requires limited processing – and is therefore sought after.”
Horse Heaven Project Becomes More Promising
The soil sampling results have expanded the target area at Antimony Ridge to 1,000m × 700m. Antimony Ridge lies within the Horse Heaven Project, located in a mining-rich area. Horse Heaven lies only 6km west of the Stibnite Gold Project, a large-scale development of Perpetua Resources. Once operational, the Stibnite Gold Project is expected to produce 450,000 ounces of gold per year. It is expected to supply 35% of the U.S.’s annual antimony demand.
The proximity underscores the potential of Horse Heaven to emerge as a major supplier of critical minerals, particularly antimony. The demand for antimony in energy storage, defence, and electronics applications is steadily increasing. The Antimony market is expected to grow at a CAGR of 6.1% in 2024-2030. Estimated at USD 1,191.3m in 2023, it is projected to grow to USD 1,657.9m by 2030.
Figure 3: Projected Growth of the Global Antimony Market Size.
U.S. antimony is known for its high heat resistance and conductivity. Both these properties are beneficial for flame retardants, lead-acid batteries and ceramics. Furthermore, antimony is in high demand in the U.S. automotive sector.
Investor Outlook
Resolution Minerals (ASX: RML; OTCQB: RLMLF) is trading at $0.054, within a 52-week range of $0.007 to $0.093. The Company’s market capitalisation as of 15th September 2025 is $60.21 million. The Company’s latest exploration results at Antimony Ridge highlight the strong upside potential of the Horse Heaven Project. With assays confirming some of the highest antimony and silver grades recorded to date, the Company is well-positioned to advance towards defining a JORC-compliant exploration target.
