Resolution Minerals reports exceptional high-grade antimony and silver results at Antimony Ridge, Idaho

Jane Morgan Management

14 January 2026 – Adelaide, Australia | Resolution Minerals Limited (ASX: RML; OTCQB: RLMLF) has reported exceptional high-grade antimony, silver and gold results from a recently completed rock sampling program at the historical Antimony Ridge Mine, part of its Horse Heaven Project in Idaho, United States.

The results confirm widespread, very high-grade antimony mineralisation at surface, with assays of up to 48.7% antimony and up to 890 g/t silver, reinforcing the project’s potential as a strategically significant source of antimony in the US. Antimony Ridge is located immediately adjacent to Perpetua Resources’ Stibnite Gold Project, a large, recently permitted antimony-gold development.

Outstanding antimony and silver grades from five massive stibnite samples (an antimony sulphide mineral) collected in October 2025 from the historical Antimony Ridge Mine were as follows: 

• Sample 732005: 48.7% Sb, 270 g/t Ag and 0.69 g/t Au; 

• Sample 732006: 35.5% Sb, 223 g/t Ag and 1.07 g/t Au; 

• Sample 732007: 42.0% Sb, 200 g/t Ag and 0.85 g/t Au; 

• Sample 732008: 37.9% Sb, 890 g/t Ag and 0.81 g/t Au; and 

• Sample 732009: 31.7% Sb, 567 g/t Ag and 1.19 g/t Au. 

The five rock samples averaged 39.2% Sb and 430 g/t Ag, confirming consistently high-grade antimony mineralisation and strong silver mineralisation.

Across the five samples, grades averaged 39.2% antimony and 430 g/t silver, demonstrating consistent high-grade antimony mineralisation with strong associated precious metal values. The samples were significantly larger than typical rock chips, averaging approximately 3.6 kilograms each, and are considered representative of historical mineralisation.

The latest assays support and extend earlier rock chip and soil sampling reported in September 2025, which delineated a broad antimony-gold-silver mineralised footprint at Antimony Ridge. The current program also forms part of an initiative to collect approximately 100 kilograms of representative high-grade stibnite material for metallurgical test work.

Craig Lindsay CEO of U.S. Operations, commented:

“These results represent a significant validation of the Antimony Ridge Target and further demonstrate the exceptional grade potential of the Horse Heaven Project. Antimony grades of this magnitude are rarely reported globally, particularly exposed at surface, and the consistent association with strong silver and gold values materially enhances the projects overall value proposition. 

Importantly, Antimony Ridge is emerging as a large, coherent, high-grade system within a strategically critical jurisdiction at a time when sure U.S. antimony supply has become a national priority. With metallurgical test work underway and permitting progressing toward drilling and bulk sampling, we believe Horse Heaven is rapidly advancing toward becoming a highly strategic U.S critical minerals asset.”

Resolution has submitted the bulk stibnite samples to metallurgical laboratories in Canada and Australia for preliminary test work and mineralisation characterisation. Results from this work will be reported to the market as they become available.

In parallel, assay results are pending for the final diamond and reverse circulation drill holes completed during the 2025 drilling season at the Golden Gate target within the Horse Heaven Project. The company expects to update the market once results are received.

Near-term activities at Horse Heaven will focus on advancing permitting to enable drilling and bulk sampling at Antimony Ridge, commencing initial drill programs once approvals are received, delivering metallurgical test work outcomes, and progressing the next phase of drilling at Golden Gate.

Jane Morgan Management
Investor & Media Relations
[email protected]