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RED MOUNTAIN MINING LIMITED
Symbol	RMXFF
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Red Mountain Mining Limited (RMXFF) Exploration Results Highlight Copper Potential at Pioneer

2026-10-14 20:37 ET - News Release

Perth, Australia, Oct 15, 2026 - (ABN Newswire) - Red Mountain Mining Limited (ASX:RMX) (OTCMKTS:RMXFF), 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 report the potential for significant copper mineralisation at the Company's 100% owned Pioneer Tungsten Project, located along the eastern Margin of the Cretaceous Mount Torrey Batholith in Montana, USA.

In addition to confirming the presence of tungsten skarn mineralisation across all sampled areas, Red Mountain's initial reconnaissance sampling at the Mammoth prospect, and more detailed sampling at the Glow Worm and Greenstone prospects, has returned multiple samples including very high copper values (Table 1*).

Rockchip sampling at Greenstone and Glow Worm has returned copper values of up to 6.72% Cu and 3.92% Cu, respectively (Table 1). As can be seen on Figure 1*, high copper values are spatially associated with areas of mapped garnet skarn and are concentrated in the northern portion of the Greenstone prospect, immediately west of the Greenstone Mine Claim and through the central and southern portions of the Glow Worm prospect.

The copper potential of both Greenstone and Glow Worm was recognised historically. The Greenstone Mine has reported historical production of 96 metric tonnes of copper ore across 1908, 1909 and 1949, which reportedly yielded a total of 3.0t of copper, 4.3kg of silver and an ounce of gold. At Glow Worm, initial exploration commencing in 1919 was also focused on copper mineralisation, with six adits and four shallow shafts completed, targeting copper-stained skarn outcrop. However, there is no recorded production from the workings.

Red Mountain has also completedlimited reconnaissance sampling at the Mammoth Prospect, with only ten rock chip assay samples collected to date from the Company's Mammoth claims. Two of these samples (Table 1, Figure 2*) returned copper results of >0.1% Cu, with a very high maximum value of 19.15% Cu for a sample collected from a skarn outcrop. Like Greenstone, the Mammoth area has recorded small-scale historical copper, silver and gold production, with the Ivanhoe Mine Claims producing 5.7t of copper, 18.3kg of silver and an ounce of gold from 79t of ore mined during 1928 and 1929.

HIGHLIGHTS:

- Desktop study highlights the Copper potential at the Pioneer Tungsten Project. In addition to confirming the presence of tungsten skarn mineralisation, Red Mountain Mining's sampling at the Pioneer Tungsten Project in southwest Montana has returned multiple rock chip samples of up to 19.15% Cu (Table 1*).

- The high copper samples are concentrated at the Glow Worm prospect, in the northern portion of the Greenstone prospect, and from the Mammoth prospect, where minor copper, silver and gold production were recorded for early 20th century artisanal mining.

- Southwestern Montana is a recognised globally significant copper province, with polymetallic porphyry, vein and skarn copper mineralisation known to be associated with Late Cretaceous granitic batholiths that include the Pioneer Batholith; most significantly the Butte deposits, hosted within the Boulder Batholith, which have an estimated totalproduction and remaining resource of 37.9Mt Cu, 1.8Mt Mo, 45.7kt Ag and 79t Au, only 60km northeast of Pioneer.

- Red Mountain's US field team is finalising plans for the upcoming surface sampling program targeting both tungsten and copper mineralisation.

- As part of Red Mountain Mining's ongoing portfolio expansion in critical and strategic metals, the Company is reviewing new Copper asset opportunities to increase exposure and complement its existing Antimony and Tungsten projects which are currently being advanced.

Southwest Montana is a globally significant copper province

Southwestern Montana is a recognised globally significant copper province, with multiple examples of polymetallic porphyry, vein and skarn copper mineralisation known to be associated with a suite of Late Cretaceous granitic batholiths that includes the Pioneer Batholith; The most significant of these deposits are the Butte deposits, which are hosted by the Boulder Batholith only 60km northeastof Red Mountain's Pioneer Project (Figure 3*). The polymetallic mineralisation at Butte has been continuously mined since the discovery of placer gold mineralisation there in 1864 and has an estimated total production and remaining resource of 37.9MtCu, 1.8Mt Mo, 45.7kt Ag and 79t Au.

Tungsten mineralisation demonstrated across all four prospects at Pioneer

Red Mountain Mining's Pioneer Tungsten Project claims cover four discrete locations, the Greenstone, Glow Worm, Mammoth and Lost Creek prospects, where the eastern margin of the Uphill Creek Granodiorite is in direct contact at surface with the Snowcrest Range Group (Figure 4*). Red Mountain's claims encompass Tungsten-bearing skarn mineralisation mapped and sampled in the middle of last century and a number of historical workings still visible today. The claims also lie immediately adjacent to claims purchased in November 2025 by Almonty Industries (NASDAQ:ALM) (TSE:AII) (ASX:AII) (FRA:ALI1) ; Market Cap AU$4.9 billion), which include the Gentung Tungsten Deposit, which has a total mineral resource of 6.83 Mt @ 0.315 % WO3; as well as the Ivanhoe and Lost Creek Mines, which are estimated to have collectively produced 680kt of tungsten ore in the 1950s and from 1970 to1975.

As previously reported, Red Mountain's surface sampling to date has confirmed the presence of garnet skarn hosted tungsten mineralisation at all four identified prospects, returning maximum rock chip tungstate (WO3) assay results of 0.55%WO3 for Greenstone, 0.40% WO3 for Glow Worm, 0.32% WO3 for sampling over a small portion of Lost Creek and 0.29% WO3 from reconnaissance sampling at Mammoth. In addition to the exposures of garnet skarn at surface, Red Mountain's claims also have clear geological potential for limestone-hosted tungsten-bearing garnet skarn mineralisation at shallow depths beneath overlying quartzite units, where magnetic modelling undertaken by Arrow Geosciences, indicates subsurface magnetic bodies, interpretedto represent the granodiorite source of the skarn mineralisation.

Next steps for Pioneer

USGS mapping shows that the prospective Snowcrest Range Group, which hosts both tungsten and copper skarn mineralisation at Pioneer when in contact withthe Uphill Creek Granodiorite, extends throughout the strike length of Red Mountain's claims at Glow Worm, Greenstone, Lost Creek and Mammoth (Figure 4*). At Lost Creek and Mammoth, Snowcrest Range limestone is shown in contact with the Granodioriteat surface throughout the claim area, which implies potential for additional skarn development at the surface. In the southern part of the Greenstone area, the limestone is not in direct contact with the Granodiorite at surface. However, as reportedin June, magnetic modelling undertaken by Arrow Geosciences, indicates shallow subsurface magnetic bodies, interpreted to represent the granodiorite source of the skarn mineralisation beneath the overlying limestone.

Red Mountain's exploration team is finalising plans for further mapping and sampling across the Pioneer Project. The work will expand Red Mountain's coverage beyond the areas that have been previously targeted and seek evidence of both tungsten and copper mineralisation.

Following completion of the surface sampling program, Red Mountain will prioritise targets for drill testing, with this phase of work expected to commence during the 2027 Northern Hemisphere field season.

*To view tables and figures included in the announcement, please visit:
https://abnnewswire.net/lnk/69EXQ475

About Red Mountain Mining Limited:

Red Mountain Mining Limited (ASX:RMX) 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.

Contact:

 
Mauro Piccini 
Company Secretary