Transition Metal Solutions closes $6M seed to boost copper extraction

Transition Metal Solutions raised $6 million in an oversubscribed seed round to scale its bio-based copper recovery technology. The company plans industrial pilot testing in 2026 to meet rising copper demand.

Funding details: $6 million (Seed)

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San Francisco-based Transition Metal Solutions has raised $6 million in an oversubscribed seed round led by Transition Ventures, with backing from SOSV, Dolby Family Ventures, Astor Management AG, Juniper VC, Climate Capital, and new investors including Possible Ventures, Understorey Ventures, New Climate Ventures, Essential Capital, and Kayak Ventures.

The startup develops chemical additives that enhance naturally occurring microbes in copper ores. Its platform studies the microbial communities already present in a mine and predicts which nutrients or chemicals will unlock higher copper yields. Early lab tests on low-grade sulfide ores improved copper recovery from 60% to 90%, while more complex ores showed metal leaching three times faster than conventional methods.

Founder and CEO Dr. Sasha Milshteyn said the company’s approach taps into what nature already provides, without the need for lab-grown microbes or extra infrastructure. COO Alexandra Shiluk added that the platform is designed to be cheap, fast, and easy for miners to adopt at scale.

The funding comes as global copper demand rises, driven by renewable energy, electric vehicles, and AI data centers. Copper is now on the U.S. Critical Minerals List, and richer deposits are nearly depleted. Transition Metal Solutions aims to help miners extract more copper from low-grade and challenging ores.

The company, founded in 2023 as Transition Biomining and rebranded to reflect its chemical-biological approach, is based at UC Berkeley’s Bakar Labs for Energy & Materials. Its leadership includes Dr. Suzan Yilmaz heading R&D, Vania Grandi leading go-to-market efforts, and Dr. Peter Kondos on the board.

Clara Ricard, partner at Transition Ventures, said the company offers a low-emission, scalable alternative to smelting that could reshape the industry. SOSV partner Pae Wu highlighted how the scientific insight behind the platform can translate directly to higher returns for miners without extra overhead.

The seed funding will support scaling from lab tests to industrial pilot trials, including 3-meter column experiments planned for the first half of 2026. Transition also plans to extend the platform to other critical metals, such as nickel, cobalt, gold, and zinc.

Source: Transition Metal Solutions