Rox Resources’ Youanmi Runs Ahead of DFS as Stoping Nears

Underground development at Rox Resources’ Youanmi Gold Project is running faster than the plan said it should. During August 2026 alone, the company completed 577 metres of underground mining activity, and production stoping, the point at which the mine starts pulling ore for processing, is now only weeks away.

That matters because the Definitive Feasibility Study (DFS) set out a specific development timetable, and the mine is beating it. With a Final Investment Decision (FID) approved in March 2026 and the project fully funded, Youanmi has moved from being a developer story to an execution story. First gold pour is targeted for the middle of 2027, drawn from a resource base of roughly 2.2 million ounces in Western Australia.

Here is what the August data tells you about whether the timeline holds, and which milestones over the next three months will confirm or challenge it. By the time you finish this, you will know exactly what to watch.

Underground development at Youanmi is outpacing the DFS schedule

The headline number is the outperformance itself. Underground development at United North is ahead of the rates laid out in the DFS, and Rox has now confirmed this at multiple checkpoints across 2026 rather than at a single moment.

The August 2026 total of 577 metres breaks down into two clear components:

• 431 metres of development advance across three mining zones
• 146 metres of stripping in the historic Youanmi decline

That is a meaningful step up from the 420 metres of total underground development reported as at 13 January 2026, a figure that itself came just over two months after the first decline cut was fired at the United North pit on 8 November 2025. The trajectory is steepening, not flattening.

Production stoping is the phase where the mine transitions from capital-intensive development to ore extraction, and the economics of different gold mining methods determine how quickly that transition translates into recoverable ounces and cash flow.

Ore-drive development, the horizontal tunnelling that follows the gold-bearing rock so it can be mined, is now largely finished across the first two levels at United North. Those initial levels already extend beyond what the DFS mine plan had scheduled at this stage.

The supporting infrastructure is keeping pace. Raise-boring works have taken an escapeway to the 2325mRL elevation at United North, covering the first four planned production levels, and ladder installation is due to be completed in September 2026. Access development for the initial production levels at Youanmi Main has also begun.

Managing director and chief executive Phill Wilding put the position plainly in the June shareholder update.

“Activity at United North continues to perform exceptionally well, remaining ahead of the development rates outlined in our Definitive Feasibility Study (DFS),” said Phill Wilding, Managing Director and Chief Executive Officer of Rox Resources.

For investors, the consistent, now quantified outperformance tells you the underground mining schedule carries lower execution risk today than it did at FID. The October stoping target reads as earned rather than aspirational.

October 2026 stoping start: the next milestone to watch

Production stoping, the phase where broken ore is extracted from the stopes for processing, is anticipated to begin in October 2026. That start is contingent on final assays and revisions to the geology grade-control model, and no source has confirmed stoping has commenced as of the time of writing. It remains an anticipated milestone, not a confirmed one.

The distinction matters. October marks the transition from development mode to production mode underground, and it is the near-term binary that will confirm or challenge the schedule read investors are currently carrying.

Surface construction reaches concrete and equipment delivery phase

Underground is only half the picture. The surface build at the Youanmi Processing Plant is advancing on a parallel track, and by August 2026 it had moved firmly into the concrete and equipment-delivery phase.

Bulk earthworks are finished at all locations. Concrete progress across the civil works sits as follows:

• Screen plant concreting complete
• Carbon-in-leach (CIL) plant concreting complete
• Crusher, ball mill, and ISAMill foundation works complete
• Primary crusher walls in construction
• CIL tanks in construction

The tailings storage facility, where processed ore residue is stored, is also progressing. Site clearing has been finished, work on the cut-off drain is substantially complete, and test pads have been put in place ready for outer wall construction to follow.

The more telling development is that long-lead equipment is now physically moving rather than sitting on order books. Here is where the major items stand.

The plant, being built by EPC contractor Interquip, is designed for 1,000 ktpa of throughput against a baseline mine feed of roughly 900 ktpa. On the accommodation side, the 351-room camp is now practically complete, its wastewater treatment facility has been brought into service, and the new dry mess facility opened its doors at the close of August 2026.

The DFS envisages peak annual output of approximately 176,000 ounces, and an average of about 117,000 ounces per annum over a seven-year mine life post-commissioning.

Processing plant construction is historically where WA underground gold projects encounter their delays. The fact that long-lead equipment is in transit rather than on order reduces one of the principal risks between now and first pour, and tells you Interquip and the project team are running multiple workstreams in parallel, the pattern consistent with a mid-2027 pour rather than a slip.

WA gold processing plant construction timelines are sensitive to the same labour and civil works constraints affecting Youanmi, making Brightstar’s concurrent Laverton build a live data point on what the regional contracting market is absorbing in 2026.

A fully funded project: the A$350 million debt package in context

None of the operational progress above would carry the same weight if funding were still an open question. It is not. The project is fully funded, and that is what turns the construction milestones from ambition into schedule.

The debt package totals $350 million and splits into three facilities.

The syndicate behind it consists of four banks: Société Générale, HSBC, Sumitomo Mitsui Banking Corporation (SMBC), and Westpac. Two of those are international majors, and the package includes a dedicated cost overrun facility, which tells you the project has cleared a level of institutional due diligence that materially lowers the odds of a funding-driven interruption.

The funding completed the picture alongside a $218 million equity raising and share purchase plan, finalised in December 2025. As at 31 December 2025, Rox held a cash balance of $232 million. Once both the equity and the four-bank debt syndicate were in place, the project crossed from developer to committed construction.

Canaccord Genuity captured the position ahead of the March decision.

Rox is “fully financed ahead of a Final Investment Decision,” according to a Canaccord Genuity broker note from March 2026.

Behind the funding sits the long-term ambition: roughly 150,000 ounces of gold per annum drawn from a 2.2-million-ounce resource base, with the DFS underpinning a 674 koz ore reserve at 4.8 g/t.

For anyone assessing Rox as an emerging producer, the distinction between a funded and an unfunded build is material. With the debt package and cash position in place, execution risk, not funding risk, is now the primary variable to monitor.

Grade, margin, and what the resource base supports long-term

Strip away the construction and funding detail and the question becomes: why does this project attract the attention it does? The answer is grade.

The underground resource sits at approximately 6 g/t, which positions Youanmi as a high-grade operation rather than a bulk-tonnage one. Higher grade means more gold recovered per tonne of rock processed, which supports stronger margins at a given gold price.

Here is the resource and reserve base underpinning the development:

• Total mineral resource: 12.1 Mt at 5.6 g/t for approximately 2.2 Moz
• Underground resource: approximately 2.1-2.17 Moz at roughly 6 g/t
• Ore reserve: 4.4 Mt at 4.8 g/t for 674 koz
• Underground production target: 5.7 Mt at 4.9 g/t for 900 koz

The DFS production profile and the company’s longer-term aspiration are worth separating clearly.

The gap between the DFS average of 117,000 ounces and the 150,000-ounce aspiration is the number that signals resource upside and the scale ambition behind the current build. It is worth being precise here: the DFS numbers, not the aspiration, are what underpin the funded project.

On cost, an October 2025 Canaccord Genuity note modelled all-in sustaining costs (AISC), the total cost to produce an ounce of gold including sustaining capital, at approximately $1,676/oz. That figure is broker modelling rather than a confirmed company number, and it comes with a caveat: any cost overrun, inflation in WA labour or consumables, or grade underperformance would erode the margin buffer that current gold prices imply.

Gold developer margins in 2026 are being tested by WA labour and consumables inflation that was not fully captured in DFS cost models completed in 2024 and 2025, creating a gap between the AISC figures that appear in broker notes and the costs projects are actually encountering on the ground.

For investors calibrating Youanmi against other emerging Australian producers, the grade profile is a genuine differentiator. But the cost assumptions baked into a 2025 DFS will be tested by WA labour and construction markets through 2026 and into 2027, and that is where the margin story will actually be settled.

What the next six months will decide for Youanmi

The work now shifts from what has been built to what still has to be proven. Three near-term milestones will determine whether the mid-2027 first pour holds.

1. Late September 2026: first Albion tank consignment arrives in Perth, with escapeway ladder installation scheduled the same month.
2. October 2026: production stoping anticipated at United North, pending final assays and grade-control model revision.
3. December 2026 quarter: ISAMill delivery committed.

Each is a hard data point rather than a soft one, and each will let investors recalibrate their first-pour expectations in real time.

Where WA underground project timelines most often slip

The honest framing is that early decline outperformance does not guarantee the same trajectory through stoping and plant commissioning. Bellevue Gold, a comparable WA high-grade underground development, offers the relevant precedent: ramp-up to nameplate processing capacity has historically taken several quarters in analogous projects, and commissioning of complex flowsheets is often where schedule slippage concentrates.

EY capital productivity research found that 64% of major mining projects face either cost or schedule overruns, with an average cost overrun of 39%, a baseline that makes Youanmi’s current ahead-of-schedule position a genuine statistical outlier rather than routine progress.

Three execution risk categories are live for Youanmi at this stage: sustaining underground outperformance through stoping, delivering plant commissioning on schedule, and managing WA labour and consumables cost pressure against the DFS cost model.

Put it together and the structural position is favourable. Underground is ahead of the DFS, surface construction is at concrete and equipment-delivery phase, and the project is fully funded. If you understand that plant commissioning and ramp-up, not early underground development, is the phase where WA gold timelines most often slip, you have the right mental model for the coming six months. The October stoping start and the December equipment deliveries are the next data points that will validate or revise the first-pour view.

For investors trying to reconcile Youanmi’s operational progress with how the market is pricing Rox Resources relative to its net asset value, our full explainer on gold mining equity discounts examines why developer and producer stocks persistently trade below pNAV even during strong gold price environments.

This article is for informational purposes only and should not be considered financial advice. Investors should conduct their own research and consult with financial professionals before making investment decisions. Past performance does not guarantee future results. Financial projections are subject to market conditions and various risk factors, and forward-looking statements are speculative and subject to change based on market developments and company performance.