Black Horse Mining Begins Diamond Drilling at Mt Egerton Gold Project

Drills Turn at Mt Egerton as Black Horse Mining Enters Next Major Exploration Phase

Black Horse Mining starts drilling at Mt Egerton Gold Project, marking the beginning of the next major phase of exploration at the historic Victorian mining complex. According to the 2 July 2026 ASX announcement, a high-capacity diamond drilling rig is now operating on site, with deeper targeted holes of around 500 metres expected to begin within approximately 10 days, subject to ground conditions.

Black Horse Mining Ltd (ASX: BHL) has confirmed that drilling has started inside the Waste Transfer Facility, while underground access works at the Sister Rose area are being advanced in preparation for portal and adit rehabilitation.

What Is Happening on the Ground Right Now?

Activity at Mt Egerton is reported to be progressing on several fronts in parallel. The current field programme, as outlined in the ASX announcement, includes the following elements:

• Diamond drilling underway inside the Waste Transfer Facility — Initial holes are targeting likely shaft locations so that historic underground workings can be accurately positioned within the project's 3D geological model.

• Deeper targeted holes to commence within 10 days — The high-capacity diamond rig has started work and is expected to move into deeper drilling shortly. Planned hole depths are nominally around 500 metres, though Black Horse Mining Ltd notes that final depths may change depending on ground conditions and results encountered during drilling.

• Multiple holes from a single drill site — Several holes are planned from the same drilling position. According to the announcement, this may include wedging and daughter holes, as well as possible navi-drilling to steer holes toward specific underground targets.

• Access tracks being sheeted for all-weather access — Black Horse Mining Ltd is preparing and sheeting access tracks to support the deeper drilling programme. This is intended to provide all-weather access, allowing drilling to continue regardless of short-term weather interruptions.

• Sister Rose box-cut cleared for rehabilitation works — The Sister Rose box-cut has been cleaned out in preparation for portal and adit refurbishment. These works are expected to commence within days of the announcement and are described as a key step toward accurately locating the Sister Rose shaft and refining the 3D geological model.

Regarding the programme's significance, Managing Director and CEO David Frances stated: "We are excited to begin the deeper testing of the stratigraphic and structural setting of the mineralised system and the 3D model of the historical workings. We also expect work on the Sister Rose portal and adit to commence imminently which will be instrumental in aiding the location of the Sister Rose shaft and hence pinning down one end of the 3D model."

For investors, this combination of drilling and underground access preparation indicates that Black Horse Mining Ltd is moving from planning to an active subsurface testing phase at Mt Egerton, with near-term catalysts tied to drilling progress and underground mapping.

The Sister Rose Adit: A Critical Piece of the Puzzle

According to the ASX announcement, the Sister Rose area is central to Black Horse Mining Ltd's near-term work programme at Mt Egerton. Sister Rose is a historical underground working accessed via a box-cut, portal and adit. The company has already completed box-cut clearing and is preparing to re-establish the portal and adit.

Once access is restored:

• The Sister Rose shaft is expected to be located more accurately.
• This shaft location can then be correlated with historic mine plans and surface survey data.
• The information will be used to position the 3D geological model of the underground workings more precisely.

In practical terms, Sister Rose acts as a key reference point within the broader Mt Egerton mining complex. Historic mine workings at depth are often only partially mapped or tied to older survey systems.

By physically identifying the exact location of the Sister Rose shaft, Black Horse Mining Ltd expects to improve the accuracy of its 3D geological model, which in turn is used to position current and future drill targets. The ASX announcement states that work on the portal and adit is expected to be underway within a few days of 2 July 2026, following the completed clean-up of the box-cut.

Educational Section: Understanding the Key Techniques at Mt Egerton

The Mt Egerton programme uses several standard exploration and mining terms that may not be familiar to all investors. The following explanations summarise the main concepts mentioned in the ASX announcement and outline why they matter.

Glossary of Key Terms

Why These Techniques Matter for Investors

Using diamond drilling, directional methods and a 3D model-driven approach has several implications:

• Higher quality geological information — Diamond core provides detailed data on rock type, alteration and veining, which is essential when assessing a complex historic gold system.

• Targeted drilling — Directional drilling and daughter holes allow multiple high-priority targets to be tested from one site, which can make exploration spending more efficient.

• Better integration with historical data — The combination of a 3D model and physical underground validation through the Sister Rose adit helps link historic mine workings with modern drill holes, improving confidence in any future resource interpretation.

For investors tracking Black Horse Mining Ltd, these techniques are typical of more advanced exploration stages where geological understanding is refined, rather than early-stage wide-spaced reconnaissance drilling.

Why This Phase of Exploration Is Significant

The current programme at Mt Egerton is described in the ASX announcement as the next major phase of exploration. Furthermore, the significance of this phase can be broken into several core elements.

1. Deeper Testing of the Mineralised System

The planned deeper holes, at around 500 metres depth, are expected to test below areas influenced by historical mining and shallower work. According to the announcement, these holes are designed to:

• Test the stratigraphic and structural setting of the gold mineralised system.
• Evaluate the current 3D geological model of the Mt Egerton mining complex.
• Gather information that may highlight extensions of mineralisation at depth, if present.

This type of deeper drilling is often used to answer key questions about whether gold-bearing structures continue below known workings and how they change in orientation or thickness.

2. Efficient, Model-Driven Drilling Strategy

By drilling multiple holes from the same site, and considering the use of wedging, daughter holes and possible navi-drilling, Black Horse Mining Ltd is aiming to collect more geological information from each drill set-up. Key features of this strategy include:

• Cost control — Fewer drill pads can reduce earthworks, mobilisation and site costs.
• Dense data near key structures — Multiple daughter holes from a single parent hole can test a range of targets around a central point.
• Direct testing of model predictions — Directional techniques allow the team to aim at specific features indicated by the 3D model or by historical data.

For investors, such an approach may indicate that the company is focusing on higher-confidence targets informed by existing data, rather than broad regional drilling.

3. Validation and Refinement of the 3D Geological Model

The ASX announcement highlights that locating the Sister Rose shaft through adit access will help pin down one end of the 3D model of the underground workings. This process has several steps:

1. Re-establish the Sister Rose portal and adit.
2. Physically confirm the position of underground workings and the shaft.
3. Tie this information back to surface survey coordinates.
4. Adjust the 3D model so that underground mine plans and modern survey data line up.

This type of model validation is critical in historic mining districts where old records may have positional inaccuracies. Once validated, the refined model can guide both near-mine and deeper drilling more reliably.

4. Victorian Gold Context

Mt Egerton is located in Victoria, a long-established gold region with extensive historical production. The announcement does not provide new production or grade figures for Mt Egerton itself; however, it situates the project within a known gold mining jurisdiction with existing regional infrastructure, a track record of historical gold operations, and geological settings that have previously hosted economic gold mineralisation.

For investors, the combination of a Victorian location and a historic mining complex may be of interest when assessing the exploration potential of Black Horse Mining Ltd relative to peers.

What Comes Next: Upcoming Milestones to Watch

Based on the timeline outlined in the 2 July 2026 ASX announcement, the next period is expected to be active in terms of field work and potential news flow.

Key Milestones and Indicative Timing

Each of these steps provides data that may feed into future market updates from Black Horse Mining Ltd, depending on results and operational progress.

Why Investors Should Keep a Close Eye on Black Horse Mining

The Mt Egerton update positions Black Horse Mining Ltd as an explorer in an active, data-driven phase of work at a historic gold project. Several features of the current programme may be relevant for investors assessing the company:

• Integrated drilling and underground access — Drilling at the Waste Transfer Facility and access work at Sister Rose are progressing simultaneously. This may shorten the timeframe needed to align underground observations with surface drilling and the 3D model.

• 3D model-based target selection — The ASX announcement emphasises the role of the 3D geological model in planning deeper drilling. For investors, this indicates that new holes are being placed with reference to both historical mine data and interpreted geological structures.

• Focus on deeper parts of the system — Planned hole depths of around 500 metres suggest that Black Horse Mining Ltd is testing below previously mined or shallowly tested areas. If mineralisation continues at depth, this could have implications for the future potential scale of the system, subject to future resource work and economic studies.

• Clear programme of near-term activities — The combination of drilling start, imminent deeper holes and Sister Rose rehabilitation provides a visible pipeline of operational milestones which may translate into regular technical updates.

Key takeaway for investors: Black Horse Mining starts drilling at Mt Egerton Gold Project with a high-capacity diamond rig on site and underground access works at Sister Rose ready to commence. The planned deeper drilling to around 500 metres, combined with efforts to accurately locate the Sister Rose shaft and refine the 3D geological model, is expected to provide critical geological information over the coming weeks and months for assessing the project's gold exploration potential.

Ready to Learn More About Black Horse Mining's Mt Egerton Gold Project?

Black Horse Mining Ltd (ASX: BHL) is now in an active, model-driven exploration phase at Mt Egerton, with a high-capacity diamond rig on site, deeper 500-metre holes imminent, and underground access works at Sister Rose set to commence. For investors looking to follow the progress of this historic Victorian gold project and assess the company's exploration potential, visit the Black Horse Mining website for the latest updates, announcements, and project information.