Watershed’s 198% IRR Is Real, but Built on Borrowed Time

A 198 per cent pre-tax internal rate of return on a $274 million investment is not a number you celebrate. It is a number you interrogate.

That figure sits at the top of the Preliminary Economic Evaluation (PEE) that Tungsten Mining published in June 2026 for its Watershed project in far north Queensland. The headline economics are, by any reasonable measure, exceptional. But the study arrives at a specific and awkward moment in the project’s lifecycle: the numbers are compelling, the financing is unresolved, the Definitive Feasibility Study (DFS) is still in progress, and the Final Investment Decision (FID) window is September 2026.

The gap between what those economics say and what an investor actually needs to resolve before treating them as real is where this analysis lives. After reading it, you will understand how to read the project’s returns in context, what the financing strategy is engineered to achieve, where the genuine geological and macro risks sit, and what milestones to watch before the FID window closes.

What the June 2026 economics actually say

Start with the raw figures, because they are the reason anyone is paying attention.

The June 2026 PEE models a pre-tax Net Present Value discounted at 8 per cent (NPV₈) of $1.31 billion, a pre-tax IRR of 198 per cent, and pre-production capital expenditure of $274 million, carrying a tolerance band of plus or minus 25 per cent. Capital payback lands at just nine months from first ore.

The operating profile behind those returns is equally striking:

• Life-of-mine operating margin: 56 per cent
• Unit operating cost: approximately $594 per metric ton unit (mtu) of tungsten trioxide (WO₃)
• Payback: nine months from first ore

A metric ton unit is the standard trading measure for tungsten, equal to 10 kilograms of contained WO₃. Hold that context, because the entire economic case rises and falls on the price assigned to it.

To see how much price drives the output, compare the current study against the last full feasibility work on the asset. Former owner Vital Metals completed a DFS in 2014 using an average Ammonium Paratungstate (APT) price of US$455/mtu. The June 2026 PEE models a spot APT price of roughly US$3,140/mtu. The variable that transforms a modest project into a spectacular one is not the geology. It is the price deck.

One classification point matters more than the celebration around the headline figures. This is a Preliminary Economic Evaluation, not a Definitive Feasibility Study, and an AACE Class 2 capital estimate (accurate to roughly plus or minus 15 per cent) is still in preparation to support the FID. The economics are real within their assumptions. They are not yet DFS-grade.

Why the price path assumption is the number to watch

The single most important input in the model is not the spot price. It is the shape of the curve.

The PEE assumes APT falls from that US$3,140/mtu May 2026 spot level to a long-term price of US$1,000/mtu by June 2030. That descent matters because the 198 per cent IRR is generated overwhelmingly in the mine’s earliest years, when the model still assigns near-peak prices to production. The project is effectively banking on capturing an elevated near-term price before the curve normalises.

The read you should take is this: the return is not built on a static high-price assumption that inflates every year of the mine plan. It is built on a rapid harvest of a temporary premium. That distinction is decisive, because detailed price sensitivity modelling has not yet been published at DFS-grade precision. Until it is, the speed of that price decline remains the most material gap in the investment case.

The resource base and what the geological caveats mean for project confidence

The economics rest on a resource that recently got bigger, and that is a genuine milestone.

Following a 15,000-metre drilling campaign completed in April 2026 targeting high-grade, near-surface mineralisation, the Watershed resource was upgraded to 69.7 million tonnes grading 0.11 per cent WO₃. That upgraded base underpins the PEE’s projected eight-year mine life, with the processing plant scheduled to run for a further seven years.

Then comes the caveat that reframes how much confidence those numbers deserve.

The production target relies partly on Inferred Mineral Resources. Under the JORC Code, Inferred is the lowest confidence category, meaning the tonnage and grade are estimated from limited geological evidence and sampling.

JORC resource classification draws a hard line between what geologists have drilled to high confidence and what remains inferred from limited evidence; the production schedule implication of that split is often more consequential than the total tonnage headline.

There is a low level of geological confidence associated with Inferred Mineral Resources. There is no certainty that further exploration will result in conversion to higher-confidence categories, or that the production schedule built on them will be realised as modelled.

This is not a reason to dismiss the resource. It is a reason to calibrate. A portion of the eight-year mine plan sits on ground that has not yet been drilled to Indicated or Measured confidence, which means the production schedule carries technical uncertainty the headline NPV does not fully communicate.

The PEE also flags specific operational geology challenges that an investor should weigh alongside the tonnage figure:

• The “poddy” nature of the tungsten mineralisation, meaning it occurs in irregular, discontinuous pockets rather than a uniform, predictable body.
• Initial ridge-cutting operations in steep terrain, which require smaller equipment and add complexity to early mining and scheduling.
• Management of potentially acid-forming (PAF) waste, which requires specific cladding strategies to prevent acidic runoff.

For an investor, the takeaway is a calibrated one. The resource upgrade genuinely underpins the project’s scale, but the split between Inferred and higher-confidence categories determines how much of the production target you should treat as high-confidence versus contingent on drilling success. That geological conversion is the risk to track through the forthcoming DFS.

The financing architecture: from a $53 million placement to a $274 million project

The economics and the geology are only half the story. The harder question is how a company assembles $274 million in project capital under a compressed timeline.

The foundation was laid in January. Tungsten Mining completed a $53 million placement, announced 27 January 2026, issuing approximately 278.9 million new shares at $0.19 to institutional and professional investors. That raise funds the working capital for the DFS, drilling, and engineering workstreams. It does not fund construction.

Bridging the gap from $53 million raised to $274 million required is the job of a dedicated debt strategy. Tungsten Mining has engaged specialist mining finance adviser Cutfield Freeman & Co Ltd to build a funding stack designed around non-dilutive instruments, meaning capital sources that do not issue new shares and dilute existing holders.

The strategy targets 30 to 50 per cent of pre-production capital from offtake prepayments, with advanced negotiations underway with global traders and refiners for long-term supply contracts.

Offtake prepayments are effectively advance payments from buyers who commit to purchasing future production, providing upfront capital in exchange for secured supply. Alongside them, the strategy is evaluating private credit, bond-style debt, strategic investment, and government-backed grant or funding programmes in both Australia and the United States, positioning Watershed within the wider critical minerals funding agenda.

The Australian government critical minerals support programmes include Export Finance Australia’s A$4 billion Critical Minerals Facility, the Northern Australia Infrastructure Facility, and the National Reconstruction Fund, each representing a potential non-dilutive capital source that projects with Watershed’s supply-diversification credentials are positioned to pursue.

The gap between what has been raised and what is required is not itself the problem. The problem is compression. These financing workstreams are running in parallel with the DFS and secondary approvals inside the same September 2026 window, which leaves almost no margin for slippage in any one of them. The offtake prepayment pathway in particular requires binding long-term contracts to be signed before FID, which makes the status of those negotiations the most material near-term catalyst to watch.

What comparable project finance deals tell investors about the timeline

Precedent deals give a realistic sense of how long this takes.

Almonty Industries secured a US$75.1 million project-finance facility from Germany’s state-owned KfW IPEX-Bank for its Sangdong tungsten mine, structured with a 6.25-year tenor, repayment holidays during construction, and pricing at LIBOR/SOFR plus roughly 2.3 to 2.5 per cent, with final drawdowns taking several years to complete by January 2025. Some additional details reported around that facility, including cost-overrun and debt-service reserve guarantees, remain unverified in the available research and should be treated as indicative rather than confirmed.

King Island Scheelite’s Dolphin project in Tasmania offers a second reference point, having required a blended package of equity, a state government loan, commercial debt, and equipment financing. Specific figures on that structure are similarly flagged as unverified.

The pattern across both is consistent: financing a critical minerals mine of this complexity demands creditworthy offtake partners, multi-tranche structuring, and often government alignment, and it rarely closes on a compressed schedule.

The macro setting that makes the economics possible, and the risk that unwinds them

The genuine thesis behind Watershed is not the drill results. It is a structural supply deficit in a metal the western world cannot easily source outside China.

Global tungsten supply is heavily concentrated. In 2025, total global mine output was roughly 85,000 tonnes, of which China produced approximately 67,000 tonnes, around 79 per cent of the world total. Non-Chinese production accounted for only about 20 per cent. China also controls between 70 and 85 per cent of global downstream APT refining and powder-metallurgy capacity, which means it dominates not just the mining but the processing.

That concentration is exactly why the price catalyst arrived when it did, and it followed a clear policy sequence:

1. At the end of 2024, the United States raised tariffs to 50 per cent on several Chinese tungsten products under section 301 of the Trade Act of 1974.
2. In February 2025, China responded with new export controls on selected tungsten items.
3. Prices moved sharply through 2025: Rotterdam 65 per cent concentrate climbed from US$266 to US$551/mtu, and APT rose from US$331 to US$675/mtu.

By the time the PEE was modelled in May 2026, APT spot had reached approximately US$3,140/mtu.

The demand outlook supports the structural case. Global tungsten demand is forecast to grow from approximately 143,000 tonnes in 2025 to 210,000 tonnes by 2035, and market research firms project a compound annual growth rate of 4.5 to 9.5 per cent across that period, a range that reflects differing methodologies rather than a single consensus.

S&P Global projects a 16,000-tonne ex-China primary mine-supply gap, the most credible third-party anchor for the structural deficit thesis and the clearest quantification of why western supply diversification matters.

Here is the interpretation that should shape your thesis. Watershed’s headline economics are not a reflection of what tungsten normally earns. They reflect what it earns right now, under an extraordinary and policy-driven configuration. The same geopolitical forces generating the 198 per cent IRR are the forces that could most quickly deflate it. A trade policy reversal or geopolitical easing would compress the very price assumptions on which the PEE is built. Reading the catalyst as a policy event rather than a permanent structural shift is what separates a well-calibrated thesis from an overconfident one.

The tungsten investment case that underpins Watershed’s economics is partly structural and partly episodic: the supply deficit is real, but the magnitude of the current price spike reflects policy events that could be partially reversed on a timeline shorter than the mine’s payback period.

What September 2026 actually represents, and what investors need to see from here

Pull the threads together and the question stops being whether Watershed is a good project. It becomes what needs to materialise in the next three to six months for the thesis to stay intact.

Be precise about what a September 2026 FID would represent. It is a Board decision to proceed, contingent on DFS completion, financing close, and secondary approvals. It is not a guarantee that any of those things have already been achieved.

Three milestones carry the most decision-relevant weight:

1. Publication of the DFS with an AACE Class 2 capital estimate, which will tighten the current plus or minus 25 per cent capex tolerance toward plus or minus 15 per cent.
2. Binding offtake agreements that anchor the 30 to 50 per cent prepayment funding tranche.
3. Confirmation that secondary approvals for ground disturbance are in place.

On approvals, the project is well advanced but not complete.

Primary authorisations are largely secured: granted mining leases, an Environmental Authority for open-pit development (EPML01188313), an approved Cultural Heritage Management Plan, Indigenous Land Use Agreements, and an EPBC “not a controlled action” determination. Secondary approvals required to unlock ground disturbance are not yet confirmed as complete.

Queensland’s critical minerals approvals reform is directly relevant to the secondary approvals workstream running alongside the DFS, given that the state government has introduced streamlined pathways for projects meeting strategic resource criteria, which Watershed plausibly satisfies.

The read you should take is that the September 2026 FID is best treated as an intention rather than a fixed deadline. Your job right now is to track whether the DFS, offtake negotiations, and secondary approvals are converging on that window or beginning to drift from it. The difference between an on-time FID and a six-month delay carries real consequences for the H1 2027 production target and for how long the company burns pre-production cash before revenue arrives.

A project with genuine merit and a financing test still to pass

Watershed’s economics are exceptional by any reasonable measure, but they are built on price assumptions that reflect a specific and potentially temporary geopolitical configuration rather than a durable long-term price floor. That is the single most important lens through which to view the 198 per cent IRR.

The proximate risk is financing. The path to FID requires assembling $221 million or more in debt and offtake capital inside the same window as a DFS completion and secondary approvals, and that compression of workstreams is the most tangible near-term execution risk the company faces.

None of this diminishes the underlying story. Watershed is a genuine critical minerals development with strong macro support, a recently upgraded resource base, and an intelligently structured, non-dilutive funding strategy. But the September 2026 window is where intention has to become execution, and that transition, not the headline economics, is what investors should be watching most closely.

For investors wanting to benchmark Watershed’s execution risks against a broader set of comparable projects, our dedicated guide to tungsten mine redevelopment factors covers the operational, financing, and geological challenges that most commonly determine whether redevelopment timelines hold.

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 the forward-looking targets described here are speculative and subject to change based on market developments and company performance.