What is the history behind the Stibnite gold project, and what is unique about it?

The Stibnite Mining District in central Idaho has a rich mining history dating back to the 1890s. During World War II, it provided critical minerals for the war front. However, a century of mining activity – conducted mostly without environmental protections – left behind serious environmental challenges. Perpetua Resources' vision for the Stibnite gold project is to use modern mining to improve the site's conditions.

The Stibnite Gold Project is unique for several reasons. Firstly, it is located on an abandoned mine site in desperate need of help. Secondly, it will establish the only domestic source of antimony, a mineral that is essential for national defense. Thirdly, once operational, it will be one of the country's highest-grade, lowest-cost open-pit gold mines, with 4.8 million oz of gold reserves. Lastly, the project prioritizes community partnerships, environmental responsibility, and safe and economic mineral production.

What are the next steps moving forward to production?

Following six years of scientific study and exploratory work, and seven years of regulatory review under NEPA, the Stibnite gold project is approaching its final permitting stages. Upcoming milestones include the release of the final EIS and draft Record of Decision, with a final Record of Decision expected in 2024. The goal for the next 12 months is to secure the final NEPA stamp of approval and all ancillary permits to be ready for construction, which we anticipate will take about three years.

What is the primary economic driver of the project?

The Stibnite gold project is primarily a gold project, with antimony playing a pivotal role in the permitting process given its status as a critical mineral. In total, there are 6 million oz of measured and indicated resources, with an additional 1.2 million oz of inferred resources. Once operational, the project is expected to yield approximately 300,000 oz/y over a 15-year mine life, generating a free cash flow averaging around US$500 million annually. The all-in-sustaining costs are projected to average under US$650/oz, based on a 2020 feasibility study, and under US$450/oz over the first four years of production.

Why is antimony so important for the United States?

Antimony is a little-known hero on the critical mineral list. It is crucial in strengthening alloys and is indispensable in clean energy, national defense and technology. It has applications in solar panels, wind turbines, high-capacity storage batteries, night vision goggles, infrared protection, uniforms, military munitions, semiconductors and computers. However, the global supply of antimony has been primarily dominated by China for over a century, and currently, China, Russia and Tajikistan control 90% of the world's supply. This dependence on foreign sources highlights the importance of establishing domestic antimony production to reduce US vulnerability.

In the first six years of production, the Stibnite gold project could potentially meet an average of 35% of the US demand for antimony. Recognizing this reliance on foreign sources, Congress has included antimony in reporting requirements within the National Defense Authorization Act. Additionally, the Department of Defense has granted Perpetua up to US$24.5 million in Defense Production Act Title III funds to advance through permitting requirements and support remaining technical work. Furthermore, in August 2023, we received a US$15.5 million award to study military-grade antimony trisulfide development from on-site materials.

Is there any exploration upside at the Stibnite gold project?

We believe the district still holds substantial exploration potential, offering opportunities for resource expansion and high-priority exploration in areas such as Garnet, Scout and Upper Midnight in the project vicinity. We also have a promising pipeline of targets rich in antimony, and our geologists are actively exploring the possibility of discovering tungsten given the region's historical association with tungsten production. We intend to pursue these additional opportunities once we successfully navigate the permitting process.

What are the benefits of developing a mine in Idaho?

Idaho's commitment to balancing natural resource development with sustainability for future generations is truly commendable. We derived our name, Perpetua Resources, from the state's motto, 'Esto Perpetua,' underscoring our dedication to responsible resource stewardship. The accessibility of state government agencies and their solution-focused approach to discussions regarding permitting aspects further bolsters this commitment. From the beginning, the project has demonstrated that business, industry and the environment can work together.