Additional Strong Assays Results Extend High-Grade Antimony Mineralisation at Oaky Creek

Red Mountain Mining Limited (ASX: RMX, US CODE: RMXFF, or “Company”) a Critical Minerals exploration and development company with an established portfolio in Tier-1 Mining Districts in the United States and Australia, is pleased to announce that it has received continued strong assay results from the second tranche of assays for its auger soil sampling program at the Oaky Creek prospect at the Company’s 100% owned Armidale Antimony-Gold project in New South Wales.

HIGHLIGHTS:

• Red Mountain has confirmed the presence of multiple drill-ready Antimony targets at the Oaky Creek Prospect following the second batch of analytical results from its comprehensive auger soil sampling program at the Armidale Antimony-Gold Project
• Newly discovered stibnite vein rock samples return up to an exceptionally high grade of 28.1% Sb. The new samples collected ~600m NNW of the Oaky Creek South workings, highlight the potential for a new extension to the current mineralised system at Oaky Creek
• Conventional and auger soil sampling and rock analytical results of up to 39.3% Sb and 1.09ppm Au for Oaky Creek indicate the potential of a large-scale orogenic Antimony-gold vein system with a strike extent of ~3km at surface, which is analogous to Larvotto Resources’ Hillgrove project, Australia’s largest known Antimony deposit
• Previously identified 200m x 30m Antimony-arsenic anomaly near the Oaky Creek South Main Grid has been extended by a further 30% and remains open to the northeast, with values of up to 251ppm Sb and 1,443ppm As returned
• Soil sampling from southern end of Oaky Creek North has further supported the NNW- trending Antimony anomaly, with values of up to 137ppm Sb and 334ppm As. Aligning with previously identified conventional soil anomaly and mineralised stibnite-bearing rock sampling, providing further evidence for widespread antimony mineralisation at Oaky Creek
• Results for approximately 900 further auger soil samples collected during January and February are pending and expected to be received before the end of March. These samples will expand auger coverage at both Oaky Creek North and Oaky Creek South, including the newly collected anomalous rock sample, and will be used in conjunction with existing datasets to refine multiple orogenic Antimony vein targets ahead of planned drill-testing
• Further assays pending for Thompson Falls Antimony Project in the US following recently announced initial high-grade Antimony results

Assay results from the January-February field program across Oaky Creek North and Oaky Creek South have reported numerous highly anomalous samples including a stibnite vein sample collected ~600m NNW of the Oaky Creek South workings returning 28.1% Sb. 42 rock samples now exceed 0.5% Sb at Oaky Creek, further supporting the presence of widespread antimony mineralisation across the Oaky Creek Prospect and potentially indicating an extension to the Oaky Creek South mineralised system (see below).

Results for approximately 900 further auger soil samples collected during January and February remain pending, with assays expected before the end of March. These results will significantly expand coverage at both Oaky Creek North and Oaky Creek South (Figure 1) and will be used in conjunction with datasets for additional expected orogenic antimony vein targets ahead of planned drill testing in Q2 2026.

New Auger Assay Results Extend Antimony-Arsenic Anomaly at Oaky Creek South

As was reported in November 2025¹, initial auger sampling at the Oaky South Main Grid, located approximately 400m north-northwest of the small historical pits and shafts at Oaky Creek South, defined a coherent NE-striking ~200m x 30m Sb-As anomaly that remained open to the northeast.

Newly received results from sampling completed in late 2025 returned values of up to 251ppm Sb and 1,443ppm As (Appendix 1) and extend this anomaly ~60m further to the northeast (Figure 2). The anomaly remains open in that direction, with analytical results for sampling completed in January and February 2026 pending and represents a priority target for planned drill testing in Q2 2026.

The new results comprise approximately 180 auger soil samples collected over conventional soil anomalies at Oaky Creek South and Oaky Creek North, expanding coverage from the initial ~250 auger samples collected at Oaky Creek South in November 2025² (Figure 1).

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