Red Mountain Mining Confirms Tungsten Skarn Mineralisation at Pioneer Montana

Red Mountain Mining Confirms Tungsten Skarn Mineralisation at Pioneer Project in Montana

Red Mountain Mining Ltd (ASX: RMX) has reported analytical results for 30 rock chip samples from its 100% owned Pioneer Tungsten Project in Montana, USA. The Red Mountain Mining Pioneer tungsten project results in Montana represent a significant early-stage milestone, with one third of these due diligence samples returning more than 500 ppm WO₃ and peak values up to 3,159 ppm (0.32%) WO₃.

These results confirm the presence of garnet skarn hosted tungsten mineralisation on the company's Greenstone and Mammoth claim areas. Furthermore, they indicate grades comparable, on a sample basis, to the 6.83 Mt @ 0.315% WO₃ Gentung Tungsten Deposit located within approximately 200 m of Red Mountain Mining Ltd's Mammoth claims.

"The best results returned comparable values to the grade of Almonty's Gentung tungsten deposit, which lies within 200 m of Red Mountain's Mammoth claims," — Red Mountain Mining ASX announcement, 1 July 2026.

According to the report, further systematic sampling at the highest priority Greenstone prospect is scheduled for mid July 2026, with drill testing of targets considered the next logical step, subject to positive follow-up results.

Headline Assay Results From Pioneer Tungsten Project

The 30 rock chip samples were collected across two of the three Pioneer claim areas, Greenstone and Mammoth. As reported by Red Mountain Mining Ltd:

• 10 out of 30 samples (around 33%) contained more than 500 ppm WO₃
• Five Greenstone samples exceeded 1,000 ppm (0.10%) WO₃
• The highest WO₃ value was 3,159 ppm (0.32%) from a garnet skarn float sample at Greenstone
• A Mammoth skarn outcrop returned 2,856 ppm (0.29%) WO₃

In addition, six samples from the Greenstone area, including three with more than 500 ppm WO₃, were taken north of the current claim boundary on ground that has been staked and is expected to be granted by the end of July 2026.

Key Rock Chip Results at a Glance

WO₃ values are calculated from average W assays from two multielement suites (ME‑MS61 and ME‑MS81), as reported by Red Mountain Mining Ltd.

Relative to the adjacent Gentung Tungsten Deposit (6.83 Mt @ 0.315% WO₃), the peak rock chip grades at Pioneer are of similar order on a sample basis. The company emphasises, however, that rock chip sampling is reconnaissance focused and indicative of surface mineralisation only, with no mineral resource yet defined at Pioneer.

What Is Tungsten Skarn Mineralisation and Why Is It Important?

The Pioneer Tungsten Project results are framed around garnet skarn hosted tungsten mineralisation. For many investors, understanding what a skarn is and why it matters can help interpret these early-stage results.

What Is a Skarn?

A skarn is a hard, coarse-grained rock that forms when hot fluids from an intrusive body — a mass of molten rock that solidified underground — react with nearby carbonate-rich rocks such as limestone.

In the case of the Pioneer Tungsten Project, the Uphill Creek Granodiorite (part of the Torrey Batholith) intruded into Snowcrest Range Group carbonate-rich sedimentary rocks. Where these two rock types meet, hot fluids and heat altered the original rocks, replacing them with new minerals and forming garnet skarn. In this environment, the tungsten-bearing mineral scheelite (CaWO₄) can form in the skarn zone.

Key Terms Explained

WO₃ (tungsten trioxide / tungstate) — The standard way tungsten grades are reported. Assays measure tungsten (W), which is then converted to equivalent WO₃ content.

Scheelite (CaWO₄) — The main tungsten ore mineral in many deposits. It is a calcium tungstate mineral and the primary tungsten mineral at Pioneer.

Garnet skarn — A skarn rock rich in garnet minerals, often with pyroxene and other silicate minerals. It commonly hosts tungsten, copper and other metals.

Rock chip sample — A hand sample collected from surface outcrop, float or waste material for geochemical analysis. It provides an indication of surface mineralisation but does not define thickness or continuity.

ppm (parts per million) — A concentration unit. 1,000 ppm equals 0.10%.

Why Do Skarn Deposits Matter to Investors?

From an investor perspective, skarn-hosted tungsten deposits are of interest for several reasons:

• Predictable geometry — Once the contact between the intrusive rock and the carbonate host rocks is mapped, geologists can often follow this contact and trace where skarn is likely to occur at depth.
• Association with known districts — Skarns often form in clusters around large intrusive complexes. The Pioneer Mountains district already hosts past-producing mines and a defined tungsten resource, supporting the broader geological model.
• Potential for grade continuity — In some skarn systems, massive garnet skarn zones can be thick and continuous. Historical information for the Mount Torrey Batholith area mentions limestone-hosted garnet skarns up to 25 m thick.

These general characteristics do not guarantee economic mineralisation. However, they explain why confirmation of garnet skarn hosted tungsten at Pioneer is an important technical milestone for Red Mountain Mining Ltd.

Project Setting and Regional Context

According to the ASX announcement, the Pioneer Tungsten Project comprises three main claim areas — Greenstone, Mammoth and Lost Creek — situated along the eastern margin of the Mount Torrey Batholith in southwest Montana, specifically where the Uphill Creek Granodiorite contacts the Snowcrest Range Group carbonate-rich rocks at surface.

The company reports that the district hosts massive limestone-hosted garnet skarns up to 25 m thick containing scheelite, and that Red Mountain Mining Ltd's claims cover areas where tungsten-bearing skarn mineralisation was mapped and sampled in the mid 20th century. Several historical workings, including trenches and adits, remain visible.

Relationship to the Adjacent Gentung Deposit and Historic Mines

Red Mountain Mining Ltd's tenements sit immediately adjacent to claims acquired in November 2025 by Almonty Industries (market capitalisation around $6.7 billion, as cited in the ASX announcement). Those claims host the Gentung Tungsten Deposit at 6.83 Mt @ 0.315% WO₃, as well as the Ivanhoe (Brown's Lake) Mine and Lost Creek Mine, with an estimated combined production of approximately 680 kt of tungsten ore during the 1950s and 1970s.

Consequently, this context indicates that Pioneer is located within an established tungsten mining district with documented production and a current mineral resource adjacent to Red Mountain Mining Ltd's ground.

Geological Model and Exploration Implications

The ASX announcement describes the geological model for the Pioneer Tungsten Project in accessible terms. Tungsten mineralisation is associated with scheelite-bearing massive garnet skarns, occurring where Snowcrest Range Group limestones are in contact with the Uphill Creek Granodiorite along the eastern margin of the Torrey Batholith.

Magnetic modelling undertaken by Arrow Geosciences is reported to show subsurface magnetic bodies beneath quartzite cover, interpreted as granodiorite intrusions that could be the source of additional skarn mineralisation at relatively shallow depths below surface.

For investors, this model suggests there may be additional skarn zones below surface that are not directly visible in outcrop. Surface rock chips confirming tungsten in garnet skarn therefore provide a first layer of evidence that supports targeting these zones with drilling.

Forward Work Programme and Near-Term Catalysts

Red Mountain Mining Ltd has outlined several immediate steps for the Red Mountain Mining Pioneer tungsten project results in Montana and across its broader portfolio.

Planned Work at Pioneer Tungsten Project

According to the 1 July 2026 announcement:

1. Mid July 2026 – systematic sampling at Greenstone — Focused on the Greenstone prospect, which returned five samples above 1,000 ppm WO₃ including the peak 3,159 ppm WO₃ result, aiming to improve understanding of the extent, variability and continuity of surface garnet skarn mineralisation.
2. End of July 2026 – expected grant of Greenstone North claims — Six samples, including three above 500 ppm WO₃, lie north of the current claim boundary, with the company expecting these claims to be granted by the end of July 2026, subject to regulatory processes.
3. Potential drill testing of downdip extensions — Subject to positive analytical results, the company states it expects to move rapidly to drill testing of the downdip extensions of skarn mineralisation at one or more locations.

Parallel Activity: Armidale Antimony-Gold Project (NSW)

Alongside work at Pioneer, Red Mountain Mining Ltd reports that drilling at its Armidale Antimony-Gold Project in New South Wales is scheduled to commence in July 2026, with a drilling contractor already secured. The project has previously delivered rock chip samples grading up to 39.3% Sb (antimony).

For investors, this means there are multiple potential newsflow events in the near term, spanning Pioneer Tungsten systematic sampling, potential drill target definition, and commencement of results from Armidale Antimony-Gold.

Investment Considerations: Positioning in Critical Minerals

Red Mountain Mining Ltd presents itself as a critical minerals exploration and development company with projects in tier-1 mining districts in the United States and Australia. The 1 July 2026 ASX announcement emphasises that the company is focused on accelerating development across its tungsten and antimony assets.

Within this context, the Red Mountain Mining Pioneer tungsten project results in Montana contribute several elements to the investment case:

• Confirmation of target mineralisation style — Rock chip sampling has confirmed garnet skarn hosted tungsten on the Greenstone and Mammoth claims, consistent with the established geological model for the district.
• Proximity to a large tungsten resource and historic production — The project sits adjacent to Almonty's Gentung Tungsten Deposit (6.83 Mt @ 0.315% WO₃) and historical producers Ivanhoe and Lost Creek.
• Early-stage but data-driven pathway — With reconnaissance sampling completed and systematic follow-up planned, the progression towards drill testing is clearly described.
• Commodity focus on tungsten and antimony — Tungsten is identified as a critical mineral in several Western jurisdictions, and antimony is also widely regarded as strategically important.

Why Monitor Ongoing Results From Red Mountain Mining Ltd?

The 1 July 2026 exploration update on the Red Mountain Mining Pioneer tungsten project results in Montana indicates that the company has achieved its first technical objective at Pioneer: verifying the presence of surface tungsten skarn mineralisation at grades that are meaningful when compared to the nearby Gentung resource grade on a sample-by-sample basis.

Key points for investors to track from here include:

• Results from systematic sampling at Greenstone and across any newly granted Greenstone North claims.
• Any subsequent drill programme design and commencement at Pioneer, particularly targeting downdip extensions of known skarn zones.
• The outcomes of drilling at Armidale Antimony-Gold Project and how these may influence overall project prioritisation.
• Ongoing refinement of the geological model around the Uphill Creek Granodiorite and Snowcrest Range Group contacts, including any new geophysical or structural interpretations.

As analytical and drilling data accumulate, investors will be better positioned to assess how Pioneer fits within the broader critical minerals portfolio of Red Mountain Mining Ltd and how the project's tungsten potential may evolve relative to its well-established district neighbours.

Want to Track Red Mountain Mining's Progress at Pioneer and Beyond?

Red Mountain Mining Ltd (ASX: RMX) is advancing a compelling critical minerals portfolio across Montana and New South Wales, with systematic sampling at Greenstone and drill programmes at Armidale both scheduled for July 2026. For investors seeking to follow the company's next steps at the Pioneer Tungsten Project and stay across upcoming newsflow, visit Red Mountain Mining's investor hub to access the latest announcements, project updates, and company information.