Archimedes Underground PEA: $127M NPV, 23% IRR
i-80 Gold Corp.'s Archimedes Underground in Nevada, USA (Eureka County, Ruby Hill Property) has a Preliminary Economic Assessment (PEA) outlining an after-tax NPV of $127M, an after-tax IRR of 23%, and initial capital of $49M. The mine plan runs 10 years at about 101.9 koz Au per year.
i-80 Gold Corp.'s Archimedes Underground has reported Preliminary Economic Assessment (PEA) results for the gold project in Nevada, USA (Eureka County, Ruby Hill Property). The study headlines an after-tax net present value of $127M at a 5% discount rate. It reflects i-80 Gold Corp.'s (IAU.TO) latest disclosed economics for the asset.
Economics. The after-tax NPV is $127M using a 5% discount rate. After-tax IRR is 23%. Initial capital expenditure is estimated at $49M. All-in sustaining costs are pegged at 1893 USD/oz Au. Economics are based on $2,175/oz Au (base-case); also $2,900/oz and $3,000/oz sensitivities.
Production and mine plan. The project envisions an underground operation. Life of mine is 10 years. Average annual production is approximately 101.9 koz Au. Average head grade is 7.0 g/t Au. Metallurgical recovery averages 90%.
These figures are extracted from i-80 Gold Corp.'s technical disclosures and reflect the most recent PEA 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 |
|---|---|---|---|
| Indicated | — | 7.6 g/t Au | 436 koz Au |
| Inferred | — | 7.3 g/t Au | 988 koz Au |
Our Analysis
- IRR after-tax
- 23%
higher than 11% of 96 projects we track
- NPV after-tax
- $127M
- Initial capex
- $49M
39% of NPV
- Mine life
- 10yrs
- Discount rate
- 5%
- Study price assumption
- $2,175/oz Au (base-case); also $2,900/oz and $3,000/oz sensitivities
- Spot gold today
- $4,034.70/oz
The 23% after-tax IRR lands in the bottom quartile of our tracked gold projects, but it still clears the practical financing hurdle for a developer—especially one in Nevada. The 5% discount rate is a tell: it flatters the headline NPV, but the real test is whether this return can attract capital in a market where single-asset juniors often need 20%+ to secure project finance. The $127M NPV sits at roughly 0.1x market cap, which cuts both ways—it could mean the market has not priced the asset, or that it is skeptical on financing, dilution, or execution risk given the company’s size.
Capital intensity is low at 39% of NPV, reducing funding risk, but the $49M initial capex still looms large relative to market cap. The base-case price assumption of $2,175/oz is well below the current spot of $4,034.70/oz, suggesting material upside to returns if prices hold—though the study’s $2,900/oz and $3,000/oz sensitivities hint at management’s own caution. The single biggest watch-item is financing: a small-cap developer in a capital-intensive business must bridge the gap between a modest NPV and a market cap that implies limited investor conviction.
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.