Copperstone Project PFS: $421M NPV, 111% IRR
Minera Alamos Inc.'s Copperstone Project in La Paz County, Arizona, USA has a Pre-Feasibility Study (PFS) outlining an after-tax NPV of $421M, an after-tax IRR of 111%, and initial capital of $57M. The mine plan runs 6.3 years at about 46 koz Au per year.
Minera Alamos Inc.'s Copperstone Project has reported Pre-Feasibility Study (PFS) results for the gold project in La Paz County, Arizona, USA. The study headlines an after-tax net present value of $421M at a 5% discount rate. It reflects Minera Alamos Inc.'s (MAI.V) latest disclosed economics for the asset.
Economics. The after-tax NPV is $421M using a 5% discount rate. After-tax IRR is 111%. Initial capital expenditure is estimated at $57M. The study models a payback period of 1.1 years. All-in sustaining costs are pegged at 1338 USD/oz. Economics are based on Base Case $3,500/oz gold price; Spot Case $4,500/oz gold price.
Production and mine plan. The project envisions an underground operation. Life of mine is 6.3 years. Average annual production is approximately 46 koz Au.
These figures are extracted from Minera Alamos Inc.'s technical disclosures and reflect the most recent PFS on file. Compare this project against other developers and producers in our project economics database, and always verify the numbers against the original technical report before making any investment decision.
Reserves & Resources
| Category | Tonnage | Grade | Contained |
|---|---|---|---|
| Proven | 1,052 kt | 5.06 g/t Au | 172 koz Au |
| Probable | 882 kt | 4.61 g/t Au | 131 koz Au |
| Total Proven & Probable | 1,934 kt | 4.87 g/t Au | 303 koz Au |
| Category | Tonnage | Grade | Contained |
|---|---|---|---|
| Measured | 2,198 kt | 5.08 g/t Au | 359 koz Au |
| Indicated | 1,856 kt | 4.54 g/t Au | 271 koz Au |
| Total Measured & Indicated | 4,054 kt | 4.83 g/t Au | 630 koz Au |
| Inferred | 401 kt | 4.04 g/t Au | 52 koz Au |
Our Analysis
- IRR after-tax
- 111%
higher than 93% of 119 projects we track
- NPV after-tax
- $421M
higher than 40% of 189 projects we track
- Initial capex
- $57M
14% of NPV
costlier than 19% of 175 projects we track
- Payback
- 1.1yrs
slower than 17% of 102 projects we track
- Mine life
- 6.3yrs
- Discount rate
- 5%
- Study price assumption
- Base Case $3,500/oz gold price; Spot Case $4,500/oz gold price
- Spot gold today
- $4,225.70/oz
The revised study for this La Paz County, Arizona gold project moved in the right direction on every measure that matters: after-tax NPV up 13% against the prior filing, initial capex down 2%, and the after-tax IRR up three points, with mine life unchanged at 6.3 years. Direction of travel is the point. Revisions more often drift the other way as engineering firms tighten assumptions, so a PFS that gains value while shaving capital is telling you the earlier estimate was conservative rather than promotional.
The headline numbers are a 111% after-tax IRR and a $421M after-tax NPV. Those two figures sit in very different places among the 189 gold projects we track: the IRR ranks above 93% of the 119 gold projects in that comparison set, while the NPV ranks above only 40% of the 189. That gap is the honest read on this asset. The rate of return is exceptional; the absolute value is mid-pack, which is what a 6.3-year life and a modest production profile will produce even at a strong margin. Payback of 1.1 years, faster than 83% of the 102 gold projects we track, is the number that best explains the IRR: capital returns almost immediately, so the discounting has little to work on. The 5% discount rate is a reporting convention rather than an investment hurdle and should not be read as a signal either way.
Funding risk is genuinely low here. Initial capex of $57M is 14% of NPV and sits below 81% of the 175 gold projects we track, and this is one of 12 projects in the company's portfolio, so a build of this size is unlikely to require a transformative raise. The caveats are stage and price. A PFS carries roughly a plus or minus 25% estimate band and is not a build decision, so the 111% IRR should be treated as a strong indication rather than a settled outcome. The study's base case of $3,500/oz sits below today's $4,225.70/oz spot, which leaves room for upside on the base case, though the $4,500/oz spot case shows how much of the return is leverage to the gold price. The question that decides this project is whether the study's cost and recovery assumptions survive detailed engineering without eroding the margin that makes a 1.1-year payback possible.
Our take, benchmarked against the project economics in the Mining Stocks database. Figures are estimates drawn from company technical reports — not investment advice; always verify against the source filing.
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