Korea Zinc's Project Crucible fills critical gap in US minerals supply chain

Korea Zinc Chairman Choi Yun-birm was a relatively small player among the Korean business leaders who gathered in Washington last year for a presidential summit, which included much larger groups such as Samsung, SK and Hyundai Motor Group.

But Choi brought something increasingly relevant to Washington: critical minerals.

Rather than focusing primarily on investment or manufacturing, Korea Zinc highlighted its decades of experience in refining a wide range of non-ferrous metals and recovering multiple critical minerals from raw materials and smelting byproducts — a capability that addresses a key weakness in the U.S. critical minerals supply chain: limited domestic processing capacity.

Four months later, Korea Zinc unveiled Project Crucible, a proposed $7.4 billion integrated smelter and critical minerals processing facility in Tennessee, backed by the U.S. government and private investors.

The facility is designed to produce 12 types of nonferrous metals, including 11 designated as critical minerals by the U.S. government, as well as semiconductor-grade sulfuric acid. Production is scheduled to begin in 2029, with all processes targeted to be fully operational in 2030.

The company plans to build a facility roughly half the size of its Onsan smelter in Ulsan, with annual production capacity of about 540,000 metric tons.

The project’s significance lies in the processing capabilities it would bring to the U.S. at a time when Washington is seeking to reduce its dependence on China for critical minerals.

Korea Zinc’s integrated smelting technology allows multiple metals to be recovered from complex raw materials and smelting byproducts, enabling a single processing base to produce a range of critical minerals.

China dominates production of several of these materials, accounting for 99 percent of global gallium production, 70 percent of refined indium and 86 percent of refined bismuth in 2024, according to the U.S. Geological Survey.

Gallium, germanium and indium are used in semiconductors and other advanced technologies, while antimony has applications in defense and energy.

The U.S. is heavily dependent on imports: it was 100 percent reliant on imports for gallium and 85 percent for antimony in 2024, with China supplying 19 percent and 54 percent of U.S. consumption, respectively.

That combination of concentrated production and limited domestic processing has made refining capacity a strategic priority for Washington, creating an opening for Korea Zinc’s multi-metal processing expertise.

Project Crucible is being developed on the site of an existing zinc smelter in Clarksville, Tennessee, which Korea Zinc acquired from Nyrstar along with related companies earlier this year.

The company officially launched the project at the site in April and plans to expand the existing industrial infrastructure to develop the new multimetal processing complex.

Washington has backed the project with substantial financial and institutional support.

The U.S. Department of Commerce has committed up to $210 million in government funding, while the Department of Defense and other financial institutions are providing or arranging up to $4.7 billion in debt financing.

The U.S. government has also taken an equity position in Korea Zinc through Crucible JV, a U.S. government-led joint venture established to support the project. Crucible JV acquired 2.21 million newly issued Korea Zinc shares, giving it a 10.59 percent stake in the company.

In announcing the project, Commerce Secretary Howard Lutnick described it as a major step in strengthening U.S. critical mineral security.

“The project being pursued in Tennessee by Korea Zinc is a transformational deal that will change the critical minerals landscape in the United States,” Lutnick said.

The U.S. government’s decision to include Project Crucible in the FAST-41 permitting framework marked the first such case involving a Korean company. The framework coordinates federal permitting for major infrastructure projects and is intended to make the review process more predictable.

The project also cleared a key environmental review earlier this month after the U.S. Department of War completed its final environmental assessment and determined that it would have no significant environmental impacts.

Tennessee officials have presented the project as an economic security investment.

"Project Crucible is a generational investment that creates new opportunities for Tennessee families and helps secure the critical capabilities America needs to compete on the world stage,” Sen. Marsha Blackburn of Tennessee said during her visit to the site in July. “It is a vitally important project for Tennessee's continued growth."

For Korea Zinc, the project means more than an overseas investment. The company sees it as a strategic initiative that could expand its global production footprint, serving as a turning point in expanding its business beyond its existing production base.

“Through this, we expect the project to serve as a turning point for Korea Zinc to become a platform company in the global advanced materials industry,” the company official said.

The project could also deepen the economic security partnership between Korea and the U.S. by establishing an additional production base for materials used in advanced industries and diversifying critical mineral supply chains.

Project Crucible has gained backing in Washington and Tennessee, but it has also become entangled in a long-running ownership dispute at Korea Zinc.

The project’s growing profile in the U.S. has also drawn attention from Korea Zinc’s largest shareholder group, MBK Partners and Young Poong.

The group initially opposed the project, arguing that the planned issuing of new rights to fund the U.S. investment was not in the company’s interests. The group filed an injunction seeking to block the issuance, but the Seoul Central District Court rejected the request in December last year, allowing the project to move forward.

The dispute has since taken an unusual turn in the U.S. In July, MBK and Young Poong hosted a reception to introduce Project Crucible to local figures in Nashville, presenting themselves as the company’s largest shareholder group and expressing their support for the project.

Korea Zinc said it viewed the move as unexpected, given the group’s earlier opposition to the project and its concerns over the planned investment. The company subsequently filed a police complaint, alleging that the group had created the impression that it was an official participant in the project. MBK Partners and Young Poong have said their activities were legitimate shareholder actions.

The ownership dispute has not altered the broader rationale behind Project Crucible in Washington.

The Center for Strategic and International Studies has described the project as an example of the U.S. and Korea building a shared critical minerals ecosystem, arguing that the alliance is moving beyond trade toward a shared “industrial architecture.”

That alignment — between Korea Zinc's ability to recover multiple metals and Washington's need to close a critical processing gap — has transformed Project Crucible from a corporate expansion plan into a strategic U.S.-Korea supply-chain project.