➤ Perpetua Resources Corp. aims to satisfy about 35% of U.S. demand for the critical mineral antimony, a key ingredient in batteries, solar panels and wind turbines, in the first six years of production at its Stibnite operation at a former mine site in Idaho.

➤ The U.S. needs to take control of its own supply chain to be prepared for emergencies, pandemics and other contingencies, according to Perpetua Resources President and CEO Laurel Sayer.

➤ The company began work on identifying the Stibnite resource in 2010 and expects to produce approximately 115 million pounds of the silver-white metalloid over 15 years when production begins in 2027.

Perpetua Resources Corp. President and CEO Laurel Sayer. Source: Perpetua Resources Corp.

Perpetua Resources plans to provide the U.S. with a domestic source of antimony, a critical mineral used to strengthen metal alloys found in a wide array of products from batteries to wind turbines. Some researchers see promise in antimony as a substitute for graphite in lithium-ion batteries or for use in calcium-antimony liquid metal batteries. By producing antimony at an abandoned gold mine site on federal land in Idaho, Perpetua Resources aims to offset U.S. reliance on imported antimony from producers in China and Russia. In August, the company announced an agreement with the Bill Gates-backed startup Ambri Inc. to supply enough antimony to build at least 13 GWh of Ambri's new liquid metal batteries.

S&P Global Market Intelligence interviewed Perpetua Resources President and CEO Laurel Sayer on Oct. 27 to learn about the company's strategy and the need to establish domestic supply chains. The following conversation has been lightly edited for clarity and length.

S&P Global Market Intelligence: Why do you think the U.S. should strengthen and localize its critical mineral supply chain?

Laurel Sayer: I think if the COVID-19 pandemic has taught us anything, it has taught us that there's a supply chain, maybe starting with toilet paper. I mean, how many of us have waited months and months when we've had an oven break or we order simple things like a bike? All of those are connected to the supply chain.

The U.S. definitely needs to take control of its own supply chain because when emergencies or pandemics happen, we aren't prepared for it. And we don't have a good knowledge base of what should be in the supply chain. So, if we don't wake up now, we're going to be in an even bigger mess in a few years. Domestic production gives us direct access to the materials we need. It brings with it American jobs, American infrastructure and it puts the social and environmental conditions of mining in our hands. This country needs a path forward on climate and on jobs.

What more could the Biden administration be doing to build a domestic supply chain?

Well, the first one that comes to mind, and it's because where we mine antimony, we need a place to process it in the U.S. As the U.S. Commerce Department looks to find ways that we can improve this supply chain, we need to get it out of the ground here and we need to process it in the U.S. So, [the country] needs help with some government loans, to either reconstruct a processing facility that's out there that needs to improve or locate some that will assist in processing it. We need to become independent. And they're looking that way, but I think that's a gap not only for antimony, but I believe for other critical minerals as well.

An increasing number of mining and metals companies have started to set various environmental, social and governance standards. As the industry confronts its role in contributing to the world's rising greenhouse gas emissions, can you provide examples of how Perpetua Resources has approached integrating ESG standards into its project plan? And is the mining and metals sector doing enough to address the problem?

Sometimes you have to start small and take little bites. It's a big elephant. I do believe that mining is looking at that. I think we, the industry, sometimes get a bad rap from a few loud voices. And when you look into these companies, they really are trying to improve and advance ESG.

I do want to highlight the fact that we were thinking and looking and doing ESG before it was cool. We have always had this as a foundation. Reviving a brownfield site and being able to have a restoration- and remediation-focused mission, that's part of ESG. The Stibnite mining district has a long history that starts way back in 1899 when mining first started for gold and silver. On the eve of World War II, the U.S. did not have a source for the tungsten and antimony needed for the war effort. But the government found supply at Stibnite, Idaho, which then went on to produce the majority of these minerals through the war. Many legacies, however, were left behind, including unlined legacy tailings and waste rock that degraded water quality. Yet between 2002 and 2012, there were decrees [under the Comprehensive Environmental Response, Compensation and Liability Act] signed that absolved former operators and U.S. agencies from any future responsibility for the environmental conditions at this site. This means that, without private industry bringing a solution, these environmental problems will most likely continue unabated.

How do you make sure domestic mining projects such as yours are economic and can compete with the world's leading producers, including China and Russia?

As the demand for U.S. critical minerals grows, it's prudent and it's practical to look to previously mined or abandoned mine sites where impacts have already occurred. And reviving these brownfield sites brings opportunities to source critical minerals domestically, provide U.S. jobs and bring private dollars to provide environmental uplift to existing conditions. There is no green energy revolution or low-carbon future if we continue to push mineral production and technology manufacturing overseas, where we cannot control the environmental conditions and production.

While being a brownfield site, we also know that robust mineral resources are still available at Stibnite. The project economics are built on reserves of 4.8 million ounces of gold, which will allow for the processing of 148 million pounds of antimony and the restoration of legacy features. We've always known that if modern mineral redevelopment were going to happen at Stibnite, we would need to design a project that addresses the abandoned environmental legacies and brings value to our communities.

It's clear that the process of building a mine, even at an abandoned mine site, on U.S. federally managed public land is a significant undertaking. Tell me what that process has been like and what needs to change?

I think the general public is not as familiar with how much money, how much dedication, how many resources have been put into mining in America. To get a project to the finish line and have a "record of decision" takes an enormous amount of work. It takes a dedicated team that believes in what they're doing. If you are jumping through all of those regulatory hoops, and there are many — I'm not saying there shouldn't be, I'm just saying there are many — stakeholders and the public should feel comfortable in knowing that a company is committed to doing that.

We hope that we'll have the final record of decision in 2023 on the Stibnite project and production will begin in 2027. However, should everything stay on schedule from here, it will be a total of 17 years between when we first identified our resources and when we get into production. That timeline is just too long to meet the nation's clean energy supply chain goals.