News & Market Analysis: Century Aluminum And Brimstone Sign MOU To Build First Fully Domestic US Aluminium Supply Chain

Century Aluminum and Brimstone, a California-based innovator in alumina production, signed a memorandum of understanding aimed at establishing what would be the first fully domestic mine-to-metal aluminium supply chain in the United States. Under the proposed agreement, Brimstone will supply smelter-grade alumina to Century from its planned US-based production facility, removing one of the most structurally entrenched import dependencies in the American aluminium industry.

The significance of the deal lies in what Brimstone is doing differently from any previous attempt at domestic alumina production. The United States has no economically viable bauxite deposits, meaning domestic alumina has never been a realistic proposition under conventional refining technology. Brimstone has developed a process that extracts alumina from common silicate rocks quarried within the US, rather than from imported tropical bauxite. Brimstone CEO Cody Finke said the company is bringing alumina production home at a globally competitive price and that the partnership with Century would help build a resilient domestic critical minerals supply chain, strengthening national security, reducing import dependence and creating American jobs.

Century senior vice president of strategy Matt Aboud described the MOU as another step toward growing domestic capacity of what he called a critical metal, adding that securing additional domestic alumina supply would make US primary aluminium production more efficient and cost-competitive.

The US currently produces less than one-sixth of the aluminium it consumes, and China accounts for roughly 60% of global alumina and aluminium production. The Gulf crisis, which has disrupted approximately 3 million tonnes of annual primary aluminium capacity since February, has sharpened political and commercial attention on the vulnerability of import-dependent supply chains across the metals complex. Century has been moving quickly to address this structural gap on multiple fronts: in January it announced a joint venture with EGA to build a 750,000 tonne per year primary aluminium smelter in Inola, Oklahoma, the first new US greenfield smelter in nearly 50 years, and in April it restarted idle capacity at its Mt. Holly plant in South Carolina in a $50 million investment.

Brimstone's demonstration plant in Reno, Nevada is scheduled to begin operations in 2028, with the first industrial-scale facility targeting production capacity of approximately 350,000 tonnes of smelter-grade alumina per year by 2034. That timeline would place Brimstone's first full output volumes arriving as the Inola smelter approaches full capacity, covering a meaningful share of its feedstock requirements from a fully domestic source.