Great Boulder Resources (ASX:GBR) extends the growth conversation at Side Well

Great Boulder Resources has added a new dimension to the investment case at its Side Well Gold Project, with fresh drilling at Mulga Bill returning high grade gold in two new discoveries: one below the existing Resource and one west of the current Resource area.

The result set has widened the scope of what management can now test through follow up drilling, while keeping that work anchored to an already established inventory of 1.02Moz Au at Side Well.

Managing Director Andrew Paterson spoke with MarketOpen to answer key investor questions on what has changed at Mulga Bill, how the company is sequencing the next phase of drilling across Side Well, where the latest results support the case for further resource growth, and how Great Boulder is pursuing that work with approximately $12 million cash as at 1 March 2026.

What has materially changed at Mulga Bill following these drilling results, and why do the new intersections matter for the growth outlook at Side Well?

What has materially changed at Mulga Bill is that we have now intersected high grade gold both below the existing Resource and west of the current Resource area, which gives us new drilling positions around an already established part of the Side Well system.

The deeper result of 1.93m @ 574.39g/t Au from 502m, including 0.25m @ 4,434g/t Au, sits about 430m below surface, while drilling 90m west of the 642,000oz Mulga Bill Resource returned 0.74m @ 48.30g/t Au from 168.6m.

Why that matters is that this work is occurring around a resource base that is already meaningful in scale.

Mulga Bill and Eaglehawk currently contain a combined Mineral Resource Estimate of 782,000oz Au over approximately 2.5km of strike, while Side Well overall hosts 16.0Mt @ 2.0g/t Au for 1.02Moz, so these results create a basis for immediate follow up in areas that sit directly alongside existing inventory.

They do not yet determine the size of any future addition, but they do expand the range of areas now being drilled with a clear Resource context.

How does Great Boulder plan to sequence follow up drilling across the new Mulga Bill zones, deeper extensions, and other priority targets at Side Well?

Our next steps are set out clearly in the current program.

The RC rig is drilling in the gap between Mulga Bill and Eaglehawk before moving to follow up the newly discovered gold zones west of Mulga Bill in approximately 2 weeks time, including the 0.74m @ 48.30g/t Au and 0.54m @ 11.70g/t Au intersections in 25MBRCD001A, while the diamond rig is due back at Side Well this week to commence a 2nd round of drilling on the deeper Mulga Bill results.

Assays from the other 5 deep holes are also expected in the coming weeks.

At the same time, the AC rig is continuing phased drilling on early stage targets within the Eastern Corridor, and additional RC programs are being designed for Mulga Bill, Eaglehawk and Golden Bracelet.

The sequencing matters because it keeps the near term focus on areas where recent drilling has already generated specific follow up targets, while allowing the broader Side Well pipeline to keep advancing through the same program.

In what way do these results reduce risk around further resource growth, particularly below the current Resource and west of Mulga Bill?

These results matter because they shift the next stage of drilling from broad opportunity to defined targets around the existing Resource footprint.

The deeper hit of 1.93m @ 574.39g/t Au from 502m, including 0.25m @ 4,434g/t Au, was described as showing that high grade veins continue at depth, while drilling west of the current Mulga Bill Resource returned 0.74m @ 48.30g/t Au from 168.6m and 0.54m @ 11.70g/t Au from 213.43m.

The release also stated that the 2 shallower intersections in 25MBRCD001A represent 2 newly discovered gold lodes west of the Resource in an area that had received little previous attention and will be an immediate focus of follow up RC drilling. These discoveries suggest potential for parallel high-grade lodes adjacent to the current resource and potentially accessible within the same open pit footprint.

From our perspective, that is important because future work is now being directed around actual intersections located immediately adjacent to an established resource corridor.

Mulga Bill and Eaglehawk already contain 782,000oz Au over approximately 2.5km of strike, so the current drilling is adding new positions around a system that already supports a substantial inventory.

It does not yet prove the scale of further growth, but it does improve the basis on which follow up drilling is now being prioritised.

With approximately $12 million in cash and multiple rigs active, how is the company approaching resource growth while maintaining capital discipline?

We are pursuing resource growth through a program that is already structured across multiple workstreams at Side Well.

The RC rig is active between Mulga Bill and Eaglehawk and will move to the new western Mulga Bill zones, the diamond rig is returning for a 2nd round of drilling on the deeper results, and the AC rig continues phased work on earlier stage targets in the Eastern Corridor.

In parallel, additional RC programs are being designed for Mulga Bill, Eaglehawk and Golden Bracelet and the funding position gives us the ability to carry out that sequence within the current program.

Great Boulder stated that it is fully funded for the drilling program with approximately $12 million cash as at 1 March 2026, while also noting that drilling will follow up recent high grade intersections below the 122,000oz Resource at Ironbark and that multiple rigs are on site to follow up these results immediately.

In practical terms, we are advancing several parts of the project at once, but doing so within a program that is already defined and funded.

The next test of scale

Great Boulder Resources is entering its next phase of drilling with a broader set of targets around Mulga Bill and a funded program already in motion across the wider Side Well project.

The immediate task is not to overstate what has been achieved, but to convert these latest intersections into disciplined follow up work across the western Mulga Bill zones, the deeper extensions, Ironbark and the Eastern Corridor.

With additional assays expected in the coming weeks and further RC programs being designed across key parts of the project, the strategic focus now turns to how effectively that work can add to an existing 1.02Moz Au Resource base at Side Well.

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