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OPERATIONS
Armidale Antimony-Gold Project, NSW, Australia (RMX 100%)
Red Mountain's Armidale Antimony-Gold Project encompasses 391km2 of prospective ground within the Southern New England Orogen (SNEO) in north-eastern NSW. The SNEO is recognised as Australia's premier antimony province and hosts Australia's largest known antimony deposit, Larvotto Resources' ((ASX:LRV) ; Market cap ~A$700 million) Hillgrove deposit. Antimony in the SNEO occurs in hydrothermal quartz veins, breccias, and stockworks, often with associated gold and/or tungsten mineralisation.
Red Mountain's project area lies west of Hillgrove and covers part of the Peel Fault system, which has recognised potential for orogenic gold and antimony mineralisation. Several known mineral occurrences lie within EL9732, where historical small-scale shallowshafts and open pits, thought to date from the early 1900s, have exploited stibnite and gold (Figure 1*). Given the age of these workings, the little exploration conducted since and the proximity of EL9732 to the Peel Fault, RMX believes there is untested potential for antimony and gold within the tenement.
During the June Quarter, the Oaky Creek antimony prospect has continued to be the focus of RMX's exploration program within EL9732.
ORIENTATION IP SURVEY SHOWS POTENTIAL STRIKE EXTENSIONS FOR OAKY CREEK SOUTH MINERALISATION
In May, the Company engaged Fender Geophysics to complete a four-line, 6.2 line-km, orientation induced polarization (IP) survey at Oaky Creek South. The survey was designed to test the subsurface electrical response across the coherent antimony-arsenic auger soil anomaly at the Oaky Creek South Main Grid, to extend across the soil anomaly, surface quartz-carbonate-stibnite vein mineralisation and shallow historical pits and shafts at the Oaky Creek South Workings; and to cross a major fault splay of the Namoi Fault that is interpreted to be a potential major feeder structure for the orogenic antimony mineralisation at the Oaky Creek Prospect (Figure 2*).
The survey that was completed forRed Mountain collected dipole-dipole IP (DDIP) data at a spacing of 50m along three 1.6km long, 100m spaced NW-SE oriented lines and one 1.5km long SW-NE oriented line. Gradient array IP (GAIP) data was also collected along the three NW-SE oriented lines to test the relative effectiveness of the two techniques, as GAIP data can be collected more quickly and therefore is more cost-effective, particularly for large survey areas, but is less effective at detecting narrow, steeply-dipping targets, such as those expected for the Oaky Creek vein system. Due to its potential greater effectiveness, Red Mountain prioritised modelling of the DDIP data from the survey, the results of which were reported after the end of the June quarter on 9 July.
Modelled 2D chargeability cross sections for the four DDIP lines are shown in Figure 3*. The data show a clear coherent chargeability anomaly associated with anomalous auger soil antimony values, outcropping quartz-carbonate-stibnite veins and shallow historical workings at the Oaky Creek South Workings (OCSW - Figure 3). The anomaly has a maximum observed chargeability of 7.2 mV/V, compared to background values that typically range from 2 to 3 mV/V, and is most strongly developed on Line 10000N, which is the southernmost line through the OCSW, so remains open in that direction.
The 2D modelling indicates that the chargeability anomaly dips steeply to the southeast, while 3D modelling (Figure 4*) suggests that the anomaly is most strongly developed southwest of Line 10000N, and implies that it extends at least a further 150m beyond it. The anomaly is interpreted to potentially represent the presence of chargeable sulfide within steeply dipping quartz-carbonate-stibnite veins, similar to those mapped and sampled at the surface within and adjacent to the historical workings.
The modelling therefore suggests that the veins both persist to depths of greater than 100m, and potentially much deeper, below surface and that theyextend along strike over a total distance of at least 400m (Figure 4*) well beyond the ~120m surface footprint of the outcropping veins, and extending the size of the drill target at OCSW.
As can be seen on Figure 3 and Figure 4 the DDIP data also show a weak chargeability response beneath the strong antimony-arsenic auger soil anomaly at the Oaky Creek South Main Grid (OCSMG).
The maximum observed chargeability of this response, which is most strongly developed near surface on Line 20000E immediately southwest of its intersection with Line 10100N, is 3.91 mV/V. The response appears to have a near-vertical dip on Line 10100N, but has limited depth extent on the other lines. It appears shallow and near flat-lying on Line 20000E, asthis line is oriented within and parallel to the strike of the auger soil anomaly at OCSMG.
APPROVAL SECURED FOR MAIDEN DRILL PROGRAM AT OAKY CREEK
As was announced in May, during the Quarter Red Mountain also secured approval from the NSW Resources Regulator for a reverse circulation (RC) drilling program at Oaky Creek, comprising up to 32 drillholes to a maximum approved hole depth of 300m.
Red Mountain engaged contractors to complete the maiden drilling program at Oaky Creek. Dueto delays on a previous job for another client from wet weather, drilling is now expected to commence in the first week of August.
The RC drilling program is designed to test four of five compelling orogenic antimony-gold targets defined from Red Mountain's comprehensive surface rock chip, conventional soil and auger soil sampling program, completed over the past 12 months (Figure 5*). The program will drill test the coherent 300m x 30m Oaky Creek South Main Grid antimony-arsenic auger soilanomaly, which has also returned rock chip results of up to 39.3% Sb & 1.09ppm Au; the historical workings and outcropping quartz-carbonate-stibnite veins at the Oaky Creek South Workings and the chargeability anomaly that extends to the SSW; the Oaky Creek North Workings; and the Sb-bearing creek exposure to the north of it.
The approved drilling approval application does not limit Red Mountain to specific collar locations, allowing the Company the flexibility to adjust drill locations inresponse to initial results, for example to test for depth or strike extensions to early mineralised intercepts. Initial drillholes are planned to be between 100m and 150m deep, significantly shallower than the maximum approved hole depth of 300m, inorder to establish continuity of mineralisation from surface. However, the maximum depth of 300m will allow for testing of further down-dip extensions of mineralisation, if justified by early results. Orogenic antimony vein systems such as those present at Oaky Creek are known to have significant depth extent, with Larvotto Resources' analogous Hillgrove deposit known to extend over vertical depths of more than 1km.
Red Mountain's initial drilling program at Oaky Creek is expected to be completed, including assay results for all drillholes, during the September Quarter.
OAKY CREEK REPRESENTS A SIGNIFICANT 3KM LONG OROGENIC ANTIMONY SYSTEM WITH MULTIPLE DRILL-READY TARGETS
The Oaky Creek prospect features quartz-carbonate-stibnite veins and breccias hosted within a tightly folded and faulted sequence of metamorphosed Carboniferous mudstone, siltstone and fine sandstone. The mineralisation has been targeted by two groups of shallow historical pits and shafts at Oaky Creek North and Oaky Creek South.
The Company's initial sampling program at Oaky Creek comprised a 50m x 100m spaced grid soil sampling program centered on a major splay of the Namoi Fault, accompanied by rock chip sampling.
As initially reported inJune 2025, the soil sampling defines a coherent, ~1.5km long, 100-200m wide, NNW-trending >2ppm Sb in soil anomaly extending both north and south of the historical workings at Oaky Creek North and a similarly-oriented ~1km long >2ppm Sb in soil anomaly extending north from the Oaky Creek South workings.
Sampling campaigns at Oaky Creek, returned multiple rock chip samples with values of over 25% Sb and 0.1g/t Au for five different areas, with mineralised and anomalous rock samples showing astrong spatial correlation to the antimony soil anomaly (Figure 5*). When considered collectively, the soil and rock chip results indicate a significant orogenic antimony mineral system with a strike extent of 3km, which is analogous to Larvotto Resources' (ASX : LRV; Market Cap. ~AU$700 million) Hillgrove Project, which lies east of Red Mountain's project area.
Red Mountain's ~1300 sample infill hand auger soil sampling campaign across the full ~3km strike extent of the Oaky Creek prospectwas completed across the past two Quarters to tighten the Company's existing 100m x 50m spaced soil grid in order to better constrain individual high priority drill targets. This detailed systematic work has allowed the company to define five high priority orogenic antimony targets13 for drill testing at Oaky Creek (Figure 5*).
FUTURE EXPLORATION PLANS
Drill testing of the accessible priority targets at Oaky Creek is Red Mountain's highest priority for the Armidale Antimony-Gold Project during the third Quarter of 2026.
The Company also continues to work towards securing additional land access to ground truth stibnite and jarosite spectral anomalies across EL9732, in particular those that lie adjacent to known mineralisation and/or are along the known major Peel, Namoi and Cobbadah faults.
*To view the full Quarterly Report including tables and figures, please visit:
https://abnnewswire.net/lnk/80ICP2OD
About Red Mountain Mining Limited:
Red Mountain Mining Limited (ASX:RMX,OTC:RMXFF) is a mineral exploration and development company. Red Mountain has a portfolio of US, Canada and Australia projects in Critical Minerals and Gold. Red Mountain is advancing its Armidale Antimony-Gold Project in NSW, Utah Antimony Project in the Antimony Mining District of Utah, US, Fry Lake Gold Project and US Lithium projects.
Source:
Red Mountain Mining Limited
Contact:
Mauro Piccini
Company Secretary
