Pantera Minerals Reports 19.2% Antimony at Gillham, Arkansas

Pantera Minerals Delivers Standout Antimony Grades at Gillham, Setting the Stage for Maiden Drilling

Pantera Minerals Limited (ASX: PFE) has reported Phase 2 exploration results from its 100%-owned Gillham Project in southwest Arkansas, with rock chip assays returning up to 19.2% antimony, 63.8 g/t silver, 8.6% zinc, and 7.44% lead. The latest sampling has refined multiple drill targets across a project area that hosts more than 18 historical antimony and silver workings but has not previously been tested by modern drilling.

For investors following the antimony sector, the update matters because Gillham is moving from early surface work toward a maiden drilling programme. The Phase 2 results appear to strengthen the geological case for a broader mineralised system, particularly across the Stewart, May and Davis prospects, which the company has identified as current priorities.

What Has Phase 2 Uncovered?

According to the announcement, Gillham covers about 5,000 acres across two project areas: Gillham East at roughly 3,000 acres and Gillham West at about 2,000 acres. Pantera completed 30 follow-up rock chip samples and 75 soil samples across historical workings, mine dumps and recently identified geochemical targets.

The company said this work was designed to improve its understanding of the geometry, continuity and scale of mineralisation in under-sampled areas. In practical terms, that means testing whether elevated metals found at surface line up with structures and historical workings in a way that can support drilling.

The strongest Phase 2 rock chip results reported were:

These are selective grab samples, collected from surface outcrop and historic workings. As the company states in its JORC tables, rock chip samples are not representative of average grade, but they are useful for identifying where strong surface mineralisation is present.

That distinction is important. High-grade rock chips can point to a compelling exploration target, however drilling is still needed to determine thickness, continuity, orientation and grade distribution at depth.

Prospect-by-Prospect Results Refine the Drill Story

Stewart and Stewart North Emerge as Core Targets

The Stewart Prospect appears to be one of the most advanced targets in the Phase 2 update. Historical records cited by Pantera indicate that the Stewart Mine produced about 1,000 tonnes of stibnite from small-scale surface workings, giving the area an established antimony history before modern exploration began.

The latest assays added further weight to that history. Sample GR055 returned 7.55% Sb, 63.8 g/t Ag, 7.44% Pb and 8.6% Zn, while GR058 from Stewart North returned 19.2% Sb, 12.25 g/t Ag and 1.1% Pb.

The company also reported coincident soil anomalism of up to 2,660 ppm Sb along the broader Stewart and May trend. When surface rock results, soil anomalies and historical workings all line up, explorers generally treat that as a stronger indication that the underlying system merits drill testing.

For investors, Stewart stands out because it combines several favourable features:

• Documented historical production
• High-grade rock chip assays
• Supporting soil anomalies
• A place within a broader mineralised trend

That combination does not confirm an economic deposit, but it does help explain why Stewart has been elevated as a key focus ahead of maiden drilling.

May Prospect Delivers First Modern Rock Chip Assays

The May Prospect is also material in this update because Pantera said the latest results are the first modern-day rock chip assays ever received from the area. According to the announcement, May sits at the eastern limit of the historical mines and was originally opened in 1877 by the United States Antimony Company.

Historical workings followed a stibnite-bearing quartz vein striking 080° with a steep south to vertical dip. Recent assays included 9.3% Sb from GR072, 4.92% Sb from GR069, and 1.4% Sb from GR068.

Pantera said these results validate previously identified soil anomalies of up to 1,205 ppm Sb. In exploration terms, this matters because soil geochemistry is often used to define targets under shallow cover, but direct rock assays help confirm that the anomaly relates to actual mineralisation rather than background noise.

May has furthermore been ranked by the company as a high-priority drill target. Given the lack of historic modern sampling and drilling, the first drill holes here could add substantial geological information.

Antimony Bluff Helps Refine Structural Understanding

At Antimony Bluff, Pantera completed follow-up field mapping and sampling aimed at refining its understanding of the controls on mineralisation. The company said the work focused on extending the known extent of mineralisation and identifying the structural controls on the quartz veins.

The standout result was 15.0% Sb in sample GR063. Pantera also collected an additional 29 soil samples south of the prospect to test for antimony mineralisation beneath shallow cover.

While Antimony Bluff delivered one of the stronger individual assays, the company noted that soil work at Andrews Gold Prospect and Antimony Bluff has improved understanding of those lower-priority areas. This has allowed management to focus attention on Davis, Stewart and May. In exploration, deciding where not to spend capital can be almost as important as identifying the strongest targets.

Understanding the Geology: What Is a Stibnite Quartz-Vein System?

For readers less familiar with antimony exploration, Gillham is described as a structurally controlled orogenic quartz-vein antimony-silver-base metal system. This sounds technical, but the basic concept is manageable.

Stibnite is the main ore mineral of antimony. It is a sulphide mineral, meaning antimony is chemically combined with sulphur. At Gillham, the stibnite is hosted in quartz veins — bands or sheets of quartz that formed when mineral-rich fluids moved through cracks in the rock and then cooled.

The host rocks at Gillham are reported to be Palaeozoic sandstones and shales of the Stanley Formation. Mineralisation is concentrated along faults, fractures and fold hinges, which are the broken or bent sections of rock that can act as pathways for mineral-bearing fluids.

Why Does This Geology Matter to Investors?

First, this type of system can produce high-grade but structurally focused mineralisation. That means grades can be strong, but the geometry of the veins matters a great deal. Second, if the surface expressions are linked to deeper structures, then drilling may show whether those veins continue below surface.

That appears to be part of Pantera's working model, particularly where soil anomalies, rock chip assays and historical workings occur together. A few key technical terms are worth clarifying:

• Rock chip sample: A selective surface sample taken from exposed rock or old workings. It shows where mineralisation exists but does not define an average deposit grade.
• Soil anomaly: An area where metal levels in soil are above normal background levels, suggesting a possible source below.
• Structural control: The way faults, fractures or folding influence where mineralisation forms.
• Orogenic vein system: A vein system formed during periods of mountain building and crustal deformation.

"The strong correlation between high-grade rock-chip results, extensive soil anomalies and historical workings continues to support the potential for significant mineralisation at depth," said Barnaby Egerton-Warburton, Executive Chairman and CEO.

The District-Scale Picture Investors Are Watching

One of the more important takeaways from the update is not just the individual sample grades, but the scale of the mineralised footprint being outlined. Pantera said the two previously reported antimony anomalies at Stewart and May extend about 400 metres and 500 metres respectively.

Both sit within a broader 2-kilometre trend, which the company said supports the potential for a district-scale mineralised system. That does not mean a resource has been defined — no drilling has yet been completed, and no Mineral Resource Estimate has been reported. Even so, a broader trend may indicate that the project hosts more than a series of isolated small occurrences.

The current project metrics, based on the announcement, are summarised below:

The broader appeal of Gillham for some investors is also tied to location. The project is in the United States, where antimony is classified as a critical mineral. The commodity itself carries considerable relevance because of its role in industrial and defence supply chains.

What Comes Next in the Gillham Exploration Programme?

According to the ASX update, Pantera's immediate work programme will focus on advancing Gillham toward maiden drilling. The company outlined three next steps:

1. Final target ranking and drill programme design
2. Maiden drilling of priority antimony and polymetallic targets at Davis, Stewart and May
3. Ongoing assessment of additional U.S.-based critical minerals opportunities

This sequencing is typical of early-stage exploration. Surface geochemistry and field mapping are used to rank targets, then drilling tests whether those targets translate into subsurface mineralisation with enough continuity to justify further work.

What Could Drilling Answer at Gillham?

Specifically, maiden drill holes could address the following key questions:

• Whether the high-grade surface mineralisation extends to depth
• Whether the quartz veins have mineable widths or occur as narrow structures
• Whether multiple prospects connect into a broader system
• Whether silver, lead and zinc add meaningful polymetallic value alongside antimony

Those are the questions that rock chips and soils simply cannot answer on their own.

"The Phase 2 programme has refined multiple high-priority drill targets as we advance toward our maiden drilling campaign, which we believe represents a significant value catalyst for the Company," said Barnaby Egerton-Warburton, Executive Chairman and CEO.

Why Gillham Is Attracting Investor Attention

The Phase 2 results strengthen Pantera's case that Gillham warrants drilling, particularly because the district combines historical workings, high-grade surface results, and no previous modern drilling. From an investor perspective, that mix can create a high-information next step, because maiden drill holes may quickly clarify whether surface indications are supported at depth.

At the same time, the usual exploration limitations remain in place. Current results are based on selective rock chips and soil sampling, not drill intercepts or resource estimates. The geological model appears to be improving, but it still requires subsurface confirmation.

That balance is central to the investment case today. On one side, Pantera has reported surface assays up to 19.2% Sb and outlined a 2 km mineralised trend within a sizeable landholding in Arkansas. On the other, the project remains at a stage where drilling will be the key test of continuity and scale.

In summary, the ASX announcement positions Gillham as a U.S. antimony exploration project that has progressed from reconnaissance into drill targeting with a clearer geological framework. The next milestone is straightforward: whether maiden drilling at Davis, Stewart and May supports the district-scale thesis suggested by the Phase 2 surface work.

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