i-80 Gold Announces Positive Feasibility Study and Initial Mineral Reserves for Granite Creek Underground; After-Tax NPV(5%) of $118 Million at $2,750/oz Au Increasing to $598 Million at $4,500/oz Au

Granite Creek feasibility study boosts reserves but hinges on Lone Tree plant by late 2027.

What the company is saying

i-80 Gold frames the Granite Creek underground project as a major step forward, emphasizing a positive feasibility study with an after-tax NPV(5%) of $118 million at a $2,750/oz gold price, rising to $598 million at $4,500/oz and $985 million at $6,000/oz. The company highlights a 229% increase in measured and indicated resources to 859,500 ounces and an 8.5-year mine life, with proven and probable reserves of 2.20 million tonnes at 7.87 g/t Au for 556,500 ounces. Management stresses the importance of timely Lone Tree plant commissioning in Q4 2027, as future production and economics are tied to this milestone. The announcement presents detailed cost and capital figures, including $144.9 million in total capital and closure costs and $82.9 million in sustaining capital, while noting that sustaining capital is lower than previous estimates despite higher tonnage. The company signals confidence in its ramp-up plan, projecting average annual production of about 75,000 ounces from 2028–2032, but acknowledges that 2026 production will be limited to 30,000–40,000 ounces as the mine ramps up. The tone is optimistic, with forward-looking statements about ongoing drilling in 2026 and a multi-year reserve development program starting in 2027.

What the data suggests

The feasibility study provides concrete figures: proven and probable reserves of 2.20 Mt at 7.87 g/t Au (556,500 oz), measured and indicated resources of 3.73 Mt at 7.17 g/t Au (859,500 oz, up 229% from March 2025), and inferred resources of 0.89 Mt at 7.06 g/t Au (202,800 oz, down 38%). The base case after-tax NPV(5%) is $118 million at $2,750/oz gold, but this rises sharply to $598 million at $4,500/oz and $985 million at $6,000/oz, showing high sensitivity to gold prices. Projected average annual production is 75,000–75,100 ounces from 2028–2032, with cash costs of $1,827/oz and AISC of $1,915/oz in that period, but life-of-mine costs are higher at $2,076/oz (cash) and $2,273/oz (AISC). Total capital and closure costs are $144.9 million, including $49.3 million for Lone Tree, and sustaining capital is $82.9 million. Production in 2026 is expected to be only 30,000–40,000 ounces, reflecting a staged ramp-up. The project’s economics and processing capacity are contingent on the Lone Tree plant being commissioned in Q4 2027, with third-party processing and stockpiling required until then. The data is comprehensive for a feasibility study, but nearly all operating and financial outcomes are projections, not realised results.

Analysis

The announcement presents a positive feasibility study and substantial resource upgrade for the Granite Creek project, with detailed technical and economic metrics. However, the majority of key claims—such as production rates, cost estimates, and project economics—are forward-looking projections contingent on successful ramp-up, timely Lone Tree plant commissioning (Q4 2027), and ongoing drilling. While the feasibility study is a concrete milestone, actual production and cash flow benefits are long-dated, with full-scale output not expected until 2028–2032. The capital outlay is significant ($144.9M total, $49.3M for Lone Tree), but immediate earnings impact is absent, and project economics are highly sensitive to future gold prices and operational execution. The tone is optimistic, but the gap between narrative and realised progress is moderate: the technical study is robust, yet most value remains to be delivered. The signal is capped at weak_positive due to the pre-production status and reliance on projections.

Risk flags

• ●Execution risk is high due to dependence on the Lone Tree plant being operational by Q4 2027; any delay would push back full-scale production and impact project economics, as third-party processing is only available through mid-2027 and material will need to be stockpiled if Lone Tree is not ready.
• ●The project’s after-tax NPV is highly sensitive to gold prices, with the base case at $118 million but rising to $598 million at $4,500/oz and $985 million at $6,000/oz, so a lower gold price environment would significantly reduce value.
• ●Operating costs are elevated, with life-of-mine cash costs at $2,076/oz and AISC at $2,273/oz, leaving limited margin if gold prices fall or if costs overrun, especially as these are projections rather than realised figures.
• ●The capital requirement is substantial at $144.9 million (including $49.3 million for Lone Tree), and the announcement does not confirm that project financing or offtake agreements are in place, so funding and construction risks remain.
• ●Resource growth and future reserve development are tied to ongoing drilling in 2026 and a multi-year program starting in 2027, introducing geological and exploration risk as well as uncertainty about future conversion rates.

Bottom line

i-80 Gold’s Granite Creek feasibility study delivers a significant resource upgrade and a detailed economic case, but the project’s value is tightly linked to the successful and timely commissioning of the Lone Tree plant in late 2027. The base case after-tax NPV is $118 million at $2,750/oz gold, but the economics are highly leveraged to gold price and cost assumptions, with life-of-mine AISC at $2,273/oz. Near-term production will be modest, and the bulk of value is at least two years away, contingent on capital execution and operational milestones. Investors should focus on Lone Tree construction progress, cost control, and actual delivery against the projected ramp-up. The most important takeaway is that while the feasibility study marks technical progress, the investment case remains dependent on future execution and gold price stability.

Announcement summary

(NYSE:IAUX) i-80 Gold announced the results of a positive feasibility study and initial mineral reserve estimate for the Granite Creek underground gold project. The feasibility study defines an after-tax NPV(5%) of $118 million at a base gold price of $2,750/oz Au, increasing to $598 million at $4,500/oz Au and $985 million at $6,000/oz Au. Proven and probable mineral reserves are reported at 2.20 million tonnes grading 7.87 g/t Au, containing 556,500 ounces of gold, with an 8.5-year mine life. Measured and indicated underground mineral resources increased 229% versus the March 2025 PEA to 3.73 million tonnes at 7.17 g/t Au for 859,500 ounces, while inferred resources decreased 38% to 0.89 million tonnes at 7.06 g/t Au for 202,800 ounces. Average annual production is projected at about 75,000 ounces from 2028 to 2032, with estimated cash costs of $1,827/oz and all-in sustaining costs (AISC) of $1,915/oz in that period, excluding Lone Tree Plant refurbishment capital. Total capital and closure costs are estimated at $144.9 million, including $49.3 million allocated to the Lone Tree plant. Sustaining capital is estimated at $82.9 million, which is lower than the prior PEA despite higher tonnage and development. Life-of-mine cash costs are projected at $2,076/oz and AISC at $2,273/oz. Production in 2026 is expected to be 30,000 to 40,000 ounces as the mine ramps up. The project’s economics rely on processing optimization and timely commissioning of the Lone Tree plant in the fourth quarter of 2027. Granite Creek is currently ramping up, with 2026 drilling ongoing and a multi-year program planned to begin in 2027 for further reserve development and potential resource growth. The technical work is classified as a feasibility study under NI 43-101 and as a pre-feasibility study under S-K 1300, reflecting differences in reporting regimes. Granite Creek is expected to use third-party processing through mid-2027, then stockpile material for approximately six months before the planned Lone Tree commissioning. Future processing capacity is tied to the Lone Tree plant milestone.

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