Brimstone signed a letter of intent with an Oklahoma-based quarry for alumina feedstock.

The Brimstone refinery will source its feedstock from Dolese’s Roosevelt quarry in southwest Oklahoma. It aims to start pilot operations in 2025, with plans for full commercial production by the end of the decade, targeting alumina with purity levels exceeding 99% Al2O3.

The project offers an opportunity to explore alternative alumina production methods; instead of relying on traditional bauxite, Brimstone plans to utilise carbon-free calcium-bearing silicate rocks as its feedstock.

The residual silicates would then be dried and further processed into supplementary cementitious materials (SCM). While offering an alternative recovery method and the opportunity to source alumina feedstock domestically, the chosen Pederson process requires higher energy compared to the traditional Bayer process, which utilises bauxite as its feedstock.

Aligned with the Trump administration’s push to onshore US manufacturing, the project aims to strengthen the domestic alumina industry and, in turn, the aluminium industry, which has long depended on imports. In 2024, the USA imported 1.1Mt (gross weight) of alumina due to its reliance on a single domestic producer, Atlantic Alumina (Atalco). Although Atalco has the capacity to produce 1.2Mtpy, it currently only manages to operate at about a third of that volume.

This push for onshoring follows the May 2025 announcement by Emirates Global Aluminium (EGA), which stated its plans to invest US$4Bn into the construction of a primary aluminium smelter, also in Oklahoma, marking the first new facility of its kind in the USA since the 1980s. These recent moves further solidify the USA’s commitment to enhancing its domestic aluminium industry throughout the entire value chain.