Western Ridge Resources Confirms Sulphide Mineralisation at Keystone Nevada

Sulphide Mineralisation Confirmed at Keystone as Western Ridge Refines Maiden Drill Targets

Western Ridge Resources (ASX: WRX) has reported confirmed sulphide mineralisation across multiple target areas at its Keystone Project in Nevada, with the latest field program adding geological support ahead of a maiden drilling campaign planned for later in 2026. According to the ASX announcement, the work included LiDAR mapping of historic underground workings, targeted rock chip sampling, and field checks across both the original project area and recently expanded claims.

For investors, the update matters because Keystone has seen no modern drilling for more than 80 years, despite extensive historical mining for tungsten, silver and gold. The latest field observations also support the company's view that mineralisation may extend beyond the old mine areas, while recent sampling at the Marble Rock Prospect appears to align with previously identified aeromagnetic anomalies.

What the Latest Keystone Field Program Found

The field review covered a broad part of the Keystone Project. According to Western Ridge, work was completed at Keystone Main, nearby historic adits, exposed vein systems in drill pad faces, minor surface workings, and the Marble Rock Prospect within the expanded land package.

The main outcomes reported in the announcement were:

• Sulphide mineralisation identified in several vein systems during field observations
• Ten rock chip samples collected and submitted to ALS Laboratories in Reno for assay analysis
• LiDAR mapping completed across historical underground workings to improve structural understanding
• Dolly Pot crushing and panning of approximately 400 grams of dump spoil material produced a sulphide-rich tail
• Marble Rock sampling identified silver-bearing sulphides close to large aeromagnetic anomalies previously outlined by the company

The company stated that these activities form part of its targeting process ahead of the maiden drill campaign expected to commence later this year.

"Our recent field program has provided further encouragement that Keystone hosts a significant mineralised system extending beyond the historical mine workings," said Dr Matthew Cobb, Managing Director of Western Ridge Resources.

"The sampling completed at Marble Rock was highly encouraging, where historical underground workings coincide with the large aeromagnetic anomalies identified earlier this year."

One point worth noting is that the company's current observations are visual only. Western Ridge included a caution that visual estimates of sulphides should not be treated as a substitute for laboratory assays. Assay results from the submitted samples are still pending.

Why Marble Rock Has Become an Important Part of the Keystone Story

The Marble Rock Prospect stands out in this update because it appears to support Western Ridge's broader exploration model. In the announcement, the company said historical underground workings at Marble Rock occur close to previously defined aeromagnetic anomalies, and that common silver-bearing sulphides were observed in vein material.

That combination is relevant because it links three things:

1. Historic mining activity
2. Geophysical targeting
3. Current field evidence of sulphides

For an explorer, this kind of alignment can improve confidence in how targets are being ranked. It does not confirm economic mineralisation, but it may increase the likelihood that other geophysical targets across the project deserve follow-up.

The company also said the recent fieldwork validated its decision to expand the Keystone landholding. That expansion, announced previously, increased the project footprint by approximately 500% and added more historical mining localities to the portfolio.

Keystone Project Context for ASX Investors

Keystone is located in the Pershing Trend in Nevada, an area known for historic mineral occurrences and workings. Western Ridge describes the project as a high-grade silver-dominant polymetallic project, with historical associations to silver, gold and tungsten.

The lack of modern drilling is central to the investment case. Historical operations often followed visible outcropping veins or shallow underground exposures, but many old mining districts were never tested using current exploration methods such as detailed geophysics, 3D mapping and more systematic drilling.

A summary of the project context is set out below.

For investors assessing early-stage exploration companies, a project like Keystone can attract attention because it combines historical evidence of mineralisation, a large district footprint and a clear pipeline of technical work leading into first-pass drilling.

What Sulphide Mineralisation Means in Plain English

Sulphide mineralisation is a common term in mining announcements, but it can be unclear to non-specialists. At a simple level, sulphide minerals are minerals made of metals combined with sulphur. These minerals often host or occur alongside valuable metals.

At Keystone, the company referenced several sulphides observed in the field and in panned material:

• Sphalerite: a zinc sulphide mineral that can be associated with silver and other metals
• Tetrahedrite: a copper-antimony sulphide that is often linked to silver-bearing systems
• Galena: a lead sulphide mineral and a common carrier of silver in many deposits
• Pyrite: an iron sulphide often found in mineralised hydrothermal systems

In many silver and polymetallic systems, sulphides are the minerals that carry the metal values being sought. Their presence can indicate that mineralising fluids moved through fractures and deposited metals in veins.

What Is a Hydrothermal System?

Another term used in the announcement is hydrothermal system. This refers to hot fluids moving through rocks, often along fractures or faults, and leaving behind minerals as they cool. If those fluids were metal-rich, they may create sulphide-bearing veins that can later become drill targets.

Furthermore, the announcement referenced boxwork evidence of iron oxides after sulphide. In practical terms, this means sulphides were likely present in the rock and later weathered out near surface, leaving a textured iron-stained structure behind. Geologists often view this as a useful clue when mapping old mineral systems.

The Dolly Pot Result and Why It Drew Attention

One of the more interesting details in the ASX update was the use of a traditional Dolly Pot to crush and pan a small sample of dump spoil material from the Keystone Mine. Western Ridge said approximately 400 grams of discarded rock was processed, producing a sulphide-rich tail that included sphalerite, tetrahedrite, galena and possible native silver.

This does not provide grade information. The company was clear that visual results are not a proxy for assay data. However, the observation is still important for context.

The material came from historic waste rock, meaning it had previously been discarded by earlier miners. If discarded material still contains visible sulphides, that can suggest the historical workings were selective and may not have captured the broader mineralised system now being assessed with modern exploration methods.

Western Ridge's table of visual estimates stated that the panned sulphide component was estimated at less than 0.5% of the total crushed rock mass. Even so, the company views the result as evidence supporting wider prospectivity across the project area.

How LiDAR and Aeromagnetics Are Helping Shape Drill Targets

This announcement also shows how Western Ridge is layering different datasets together before drilling. That matters because early-stage exploration risk is often reduced by building a better geological model before the first holes are drilled.

Two datasets are particularly relevant here:

LiDAR Mapping

LiDAR uses laser-based remote sensing to create highly detailed 3D maps of the ground surface and old workings. At Keystone, the LiDAR survey was used to map historic underground areas and provide structural information that may help with drill hole placement.

Aeromagnetic Data

Aeromagnetic surveys measure changes in the Earth's magnetic field. These changes can highlight buried structures, rock types or alteration patterns that may be associated with mineralisation. Western Ridge had previously identified large anomalies at Marble Rock, and the current field observations appear to support those targets.

For investors, the practical takeaway is straightforward: the company is not moving into drilling based on a single datapoint. Instead, it is combining historic workings, geophysics, surface observations and laboratory sampling to refine target selection.

Western Ridge's Exploration Sequence at Keystone

According to the announcement, the current field program is part of a broader and staged exploration strategy. The sequence can be summarised as follows:

1. Acquisition of the historic Keystone Mine
2. Aeromagnetic survey highlighting multiple targets
3. Expansion of the landholding by about 500%
4. Field review, LiDAR mapping and rock chip sampling
5. Pending assays from 10 submitted samples
6. Maiden drilling campaign planned for later in 2026

This sequence is relevant because each step is intended to improve the next one. In junior exploration, the quality of target definition often has a major bearing on how informative the first drill programme becomes.

Near-Term Catalysts Investors May Watch

The latest WRX update leaves several follow-up milestones in focus.

The next immediate data point is likely to be the assay results. Those results should provide chemical confirmation of the rock chip samples and help determine how closely the visual observations align with measured metal values.

Drilling then becomes the key technical event. Surface sampling and mapping can identify targets, but drilling is typically needed to test continuity, thickness and grade below surface.

Why the Keystone Update Matters

This ASX announcement does not report assay grades or drilling intersections, so it should be viewed as an exploration progress update rather than a resource-defining event. Even so, it adds several pieces of information that are relevant to the Keystone investment case.

First, the company has reported sulphide mineralisation across multiple areas, not just at the main historic workings. Second, Marble Rock appears to support the geophysical targeting model that Western Ridge has been building. Third, the work is being completed in advance of a maiden drill programme at a project that has not seen modern drilling for decades.

That combination may matter to investors following silver-dominant polymetallic exploration in Nevada. If upcoming assays support the field observations, and if drilling later in 2026 confirms continuity at depth, Keystone could become a more closely watched exploration story. For now, the latest update suggests Western Ridge is still in the target-refinement stage, but with a clearer geological framework than it had before this field programme.

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