Boston Metal raises $75M to pivot to critical metals
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- Boston Metal raised $75 million in a new funding round backed by existing investors and India's Tata Steel Limited, bringing the company's total raised to more than $500 million.
- The company is shifting its focus from decarbonizing steelmaking — an industry responsible for about 8% of global greenhouse emissions — to producing higher-value critical metals like niobium, tantalum, tin, vanadium, nickel, and chromium.
- Boston Metal do Brasil is building a commercial facility in Brazil to process niobium, tantalum, and tin from low-grade ore; CEO Tadeu Carneiro says the plant should be ready to start up in September 2026 after roughly 18 months of construction.
- A January 2025 refractory-system failure at the Brazil plant caused molten electrolyte to leak, delaying the facility's opening and forcing Boston Metal to miss a funding milestone — the company laid off 71 employees in April as a result.
- Boston Metal's core technology is molten oxide electrolysis (MOE), which runs electric current through ore dissolved in a molten electrolyte heated to roughly 1,600 °C (3,000 °F) to separate the target metal, which collects at the bottom of the reactor.
- In early 2025, Boston Metal completed the largest run of its pilot industrial cell in Woburn, Massachusetts, producing about one ton of steel.
- Seaver Wang, director of climate and energy at the Breakthrough Institute, framed the strategic logic: "Nobody wants to pay a green premium for steel — hence niobium."
Why it matters: Boston Metal's pivot is a survival bet: with US industrial-decarbonization support waning and cash already strained by a January plant accident and 71 layoffs, the startup needs its Brazil facility online by September 2026 to prove molten oxide electrolysis works at commercial scale on premium-priced niobium and tantalum before it can return to green steel.
