The developer of the world's first single-step process for producing steel and high-purity iron at lower cost, Hertha Metals, has successfully achieved iron production at 99.95% (3N5) purity, which meets the specification required by top rare earth magnet manufacturers.

Hertha is the first US company to reach this specification with fully domestic inputs, and establishes a domestic source for a material the US currently imports almost entirely.

The milestone comes as defence manufacturers face a January 1, 2027 deadline to reduce reliance on Chinese-origin magnets and critical materials, while US industry races to qualify domestic alternatives.

Hertha operates the largest demonstration-scale single-step steelmaking facility in the US at its Conroe pilot plant, in Texas,

High-purity iron is an essential input to rare-earth magnets, making up roughly 70% by weight of the neodymium magnets used in electric vehicle (EV) motors, wind turbines, defence systems, and more. For magnet manufacturers, purity is critical. Even trace impurities can degrade magnetic strength and durability, impacting performance.

"High-purity iron is one of the least visible materials behind the magnets that power everything from EVs to defence systems, and today almost none of it is made in America,” says Hertha founder and CEO Laureen Meroueh.

She adds that the company has now demonstrated that it can produce magnet-grade iron domestically, which creates a new pathway to build a domestic supply chain.

Producing iron at this purity typically requires an electrolytic refining process with numerous processing steps.

Hertha meets the same specification through their unique pyrometallurgical process with minimal post processing, simultaneously controlling oxygen, carbon, nitrogen, phosphorus, sulfur, and residual metallic impurities in a single continuous step.

By demonstrating 3N5 purity using commercial-grade equipment, Hertha has cleared the technical bar to qualify as a viable supplier, offering a lower-cost, domestic source.

Hertha's next facility, Chalyx, will produce high-purity iron to that specification for rare earth magnet producers.

"Moving from demonstration to commercial scale shifts the hard part from the process to the build, and no plant like this has been built before," Meroueh states. 

Accordingly, Hertha has appointed steel industry veteran Alec Glenn as VP of operations to lead the buildout and engaged Mark1, which brings expertise in first-of-a-kind industrial projects, to support engineering and project development.

Glenn comes from JSW Steel USA, where he served as VP of reliability. He previously held roles at AM/NS Calvert, where he helped bring a greenfield facility online, and spent six years at Nucor Steel, beginning as an electrician. Glenn joins Hertha to lead operations through the buildout and startup of the new facility, bringing three decades of experience taking large-scale steel plants from construction to steady production.

Mark1 is a developer-as-a-service for capital-intensive, emerging industrial technologies.

Created by RMI, Third Derivative, and Deep Science Ventures, Mark1 works with technology companies to plan and develop their first commercial-scale projects, drawing on its network and experience with commercialisation of innovative industrial decarbonisation technologies.

Hertha already operates a demonstration-scale facility in Conroe, Texas, producing at a ton-per-day capacity and refining its process using commercial-grade equipment.

The company is now prepared on both quality and process to supply magnet manufacturers with cost-effective and domestic high-purity iron, starting with Chalyx, which breaks ground later this year.