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RED MOUNTAIN MINING LIMITED
Symbol	RMXFF
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Red Mountain Mining Limited (RMXFF) Systematic Exploration Underway at Pioneer Tungsten Project

2026-07-28 18:50 ET - News Release

Perth, Australia, July 29, 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, announced that the company's US-based field crew is currently on the ground completing a program of systematic rock chip sampling at the Company's 100% owned Pioneer Tungsten Project, targeting tungsten-bearing garnet skarn mineralisation along the eastern Margin of the Cretaceous Mount Torrey Batholith in Montana, USA. (Figure 1*).

HIGHLIGHTS:

- Red Mountain has commenced systematic rock chip sampling at the Company's 100% owned Pioneer Tungsten Project in Montana, USA.

- The systematic sampling is focused on Red Mountain's Greenstone and Lost Creek claims, two of three claim areas, along with the Mammoth claims, that collectively comprise the Pioneer Tungsten Project. The claims are located along the eastern margin of the Mount Torrey Batholith, which locally features massive limestone-hosted garnet skarns, up to 25m thick. These skarns are known to contain tungsten mineralisation as scheelite (CaWO4).

- Red Mountain's initial reconnaissance rock chip sampling, reported on 1 July, returned anomalous values of upto 3159ppm (0.32%) WO3 from the Greenstone claim area and 2856ppm (0.29%) WO3 from the Mammoth claims, which will be further sampled later, confirming the presence of garnet skarn hosted tungsten mineralisation at these prospects. Initial sampling did not include Lost Creek.

- Outcropping garnet skarns are reported within the Company's Greenstone and Lost Creek claims and the current round of sampling is designed to better define the surface grade, extent, variability and continuity of the tungsten mineralisation at these two sites.

- The relatively simple and well-understood geology of the Pioneer Project means that the Company anticipates that it will be able to move rapidly to drill testing of downdip extensions of skarn mineralisation, subject to positive analytical results from the current sampling.

- Red Mountain's Pioneer Tungsten Project claims encompass similar geology and lie adjacent to claims purchased in November 2025 by Almonty Industries (Market Cap AU$5.8 billion), hosting the Gentung Tungsten Deposit, with a mineral resource of 6.83Mt @ 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 1970s.

Drilling atArmidale Antimony-Gold Project, NSW, Australia:

- RMX has advised by the drilling contractor that commencement will occur during the first week of August, with the drilling rig receipt held back due to wet weather. Access tracks are in place andinitial drill sites have been prepared, positioning the Company to move directly into maiden drill testing of multiple priority targets at Oaky Creek.

SYSTEMATIC SAMPLING DESIGNED TO DEFINE POTENTIAL DRILL TARGETS

The current round of systematic sampling is focused on Red Mountain's Greenstone and Lost Creek claims, two of three claim areas, along with the Mammoth claims, that collectively comprise the Pioneer Tungsten Project (Figure 1*).

Red Mountain's initial reconnaissance rock chip sampling, reported on 1 July, returned anomalous values of up to 3,159ppm (0.32%) WO3 from the Greenstone claim area and 2,856ppm (0.29%) WO3 from the Mammoth claims, confirming the presence of garnet skarn hosted tungsten mineralisation at theseprospects. Due to time constraints, this initial sampling did not include Lost Creek. Significantly, the best results from Greenstone and Mammoth are comparable to the grade of Almonty's Gentung tungsten deposit, which lies within 200m of Red Mountain's Mammoth claims and has an estimated mineral resource of 6.83Mt @ 0.315% WO3.

Published US Bureau of Mines mapping records outcropping garnet skarn within the Company's Greenstone (Figure 2*) and Lost Creek (Figure 3*) claims and the currentround of sampling is designed to better define the surface grade, extent, variability and continuity of the tungsten mineralisation across these mapped surface exposures in order to identify areas where there is potential for tungsten mineralisationto extend down dip to the east, which, subject to positive surface assay results, will be prioritized for drill testing. Sampling is being be carried out on east-west traverses across the mapped garnet skarn mineralisation at a nominal spacing of 50m.

Where possible, representative channel samples are being collected across 5m of outcrop, with individual rock chip grab samples collected where the outcrop is not near-continuous. At Greenstone, systematic sampling will also be completed northof the current Red Mountain claim footprint over part of an area that the Company has staked and expects to be granted by the end of July 2026.

NEXT STEPS FOR PIONEER

As can be seen on Figure 2 and Figure 3*, USGS mapping shows that the prospective Snowcrest Range Group, which hosts the tungsten skarn mineralisation at Pioneer when in contact with the Uphill Creek Granodiorite, extends well beyond the area mapped by Pattee (1960) throughout the strike length of Red Mountain's claims at both Greenstone and Lost Creek. At Lost Creek, Snowcrest Range limestone is shown in contact with the Granodiorite at 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 reported in June, magnetic modelling undertaken by Arrow Geosciences 10, indicates shallow subsurface magnetic bodies, interpreted to represent the granodiorite source of the skarn mineralisation beneath the overlying limestone.

During the current two-week field visit, Red Mountain's exploration team is also undertaking initial reconnaissance mapping and rock chip sampling beyond the areasof skarn mapped by Pattee (1960) at Greenstone and Lost Creek to define areas for further follow up sampling during the current northern hemisphere field season. Further geological mapping and follow-up sampling is also planned for Mammoth during the current quarter.

Red Mountain anticipates that assay results from the current systematic sampling program at Greenstone and Lost Creek will be received by the end of August. As noted above, assuming that these results are positive, the companywill use the extent and geometry of the surface mineralisation to define down dip targets for drill testing.

PIONEER PROJECT GEOLOGY

The Pioneer Tungsten Project claims cover three discrete locations, the Greenstone, Mammoth and Lost Creekprospects, where the eastern margin of the Uphill Creek Granodiorite is in direct contact at surface with the Snowcrest Range Group (Figure 1). Red Mountain's claims encompass Tungsten bearing skarn mineralisation mapped and sampled in the middle oflast century and a number of historical workings still visible today. The claims also lie immediately adjacent to claims purchased in November 202511 by Almonty Industries ( (NASDAQ:ALM)(TSE:AII)(ASX:AII)(FRA:ALI1); Market Cap AU$6.7 billion), whichinclude 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 to 1975.

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, interpreted to represent the granodiorite source of the skarn mineralisation.

The Torrey Batholith is a large volume composite complex that forms the core of the Pioneer Mountains in southwest Montana. The batholith ranges in composition from gabbro to granite, but is dominantly granodioritic in composition. Tungsten mineralisation occurs along the entire eastern contact of the Pioneer Batholith where it is in contact with mid-Paleozoic carbonate-rich sedimentary rocks (Figure 1), but to date significant mineralisation, occurring in scheelite-bearing massive garnet skarns, has only been found where the limestones of the Snowcrest Range Group contact the Uphill Creek Granodiorite.

Significantly, there does not appear to be any skarn development or tungsten mineralisation associated with the Grayling Lake Granite, which cuts and is therefore younger than the granodiorite and associated skarn mineralisation at the Mammoth Prospect.

HISTORICAL TUNGSTEN PRODUCTION

The earliest recorded interest in the garnet skarn hosted tungsten mineralisation surrounding the Mount Torrey Batholith dates from the early 1950s, driven by the US Federal Government's strategic metal stockpiling program, with significant production recorded from the Ivanhoe and Lost Creek mines (Figure 1*).

Exploration for tungsten was carried out between 1951 and 1953 around the Ivanhoe Mine (also known as theBrown's Lake Mine), which had been mined for copper, silver and gold in 1928 and 1929, recording production of 5.7t Cu; 647 oz Ag and 1 oz Au. Open pit tungsten production from the Ivanhoe Mine commenced in October 1953 and initially ceased in 1957,with total production during this period of 567kt at an average grade of 0.35% WO3.

Similar skarn-hosted tungsten mineralisation was mined by the Minerals Engineering Company between 1952 and 1956 from a series of adits and small open pits at the Lost Creek Mine, ~5km southeast of Ivanhoe. The total recorded production from Lost Creek during this period is 19kt at an average grade of 0.18% WO3.

Both mines remained idle until 1971, when General Electric purchased the properties and rebuilt the mill at Ivanhoe, which operated until 1975. Minor Tungsten production is also recorded from the Greenstone Mine during the 1950s, with recorded production of 900kg of sorted ore, containing 1.2% WO3. It is estimated that total production from the district from the 1950s and 1970s is approximately 680kt of tungsten ore.

DRILL SITES READY TO GO AT OAKY CREEK, NSW, AUSTRALIA

Following NSW Resources Regulator approval of the proposed program, Red Mountain's Australian field team has been focused on preparations for maiden drill testing of multiple priority targets at the Okay Creek antimony prospect within the Company's Armidale Antimony-Gold Project in northeast NSW, Australia.

Access tracks are in place and initial drillsites have been prepared for the program, which will comprise up to 32 RC drillholes to a maximum depth of 300m. The Company's drilling contractor has advised that drilling is set to commence the first week of August, with the drilling rig receipt held back due to wet weather at another project. At the Armidale Project, access tracks are in place and initial drill sites have been prepared, positioning the Company to move directly into maiden drill testing of multiple priority targets at Oaky Creek.

*To view tables and figures, please visit:
https://abnnewswire.net/lnk/RHGAT2S6

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