Rare earth elements might be next for this startup's microbe-assisted technique.

Far from the massive machinery and clamor of conventional mines, a team of microbial miners is rewriting the rules of critical metals extraction. Endolith, a biotech startup, has revealed a breakthrough in biomining: using living microbes to unlock copper and lithium from previously overlooked second-rate feedstock.

In collaboration with BHP's Think & Act Differently initiative and the Unearthed mining accelerator, Endolith has successfully demonstrated that its engineered microbial system can extract significantly more copper from low-grade sulfide ores under simulated field conditions than conventional methods.

By using microorganisms to extract metals, biomining methods such as those developed by Endolith reduce the need for harmful chemicals while recovering value from low-grade ores and tailings. Major companies like Rio Tinto, Glencore, and Anglo American are backing projects that integrate this technology.

Prime targets of biomining pilot projects include gold, vanadium, cobalt, nickel, zinc, and even uranium – all of which can be extracted out of a diverse collection of overlooked resources from geothermal brines to bauxite tailings.

Endolith's initial focus on biomining copper, a workhorse energy metal that is often overlooked next to critical mineral superstars like lithium. Global demand for copper, however, is expected to double by 2035, according to S&P Global. That's roughly 50 million metric tons per year, enough to build 600 million electric cars.

But while demand ramps up, supply is slowing down. Copper ore grades have dropped 40% since 1991, and most known reserves are trapped in deposits long dismissed as poor or too complex to process economically.

These supply and demand dynamics favor the long-term success of Endolith's biomining technology.

"The prices that we'll see in metals over the next twenty years will sustain a new industry in mining waste," said John Steen, director of the Bradshaw Research Initiative in Minerals and Mining for the University of British Columbia. "When the economy feels the pain of high metal prices, that's when we develop innovations to do it cheaper and better."

Endolith's small but mighty microbes

Endolith's process begins with a diagnostic scan of existing heap leach, raffinate (a liquid from which impurities have been removed by solvent extraction), and other fluids to map existing microbial activity and to obtain a baseline of current operations. This analysis helps determine how microbes are currently working at each site. Then, custom-grown microbes cultivated on-site in bio-hatcheries are introduced to enhance copper recovery.

A cloud-based AI platform monitors and optimizes the entire system in real time, adapting to environmental conditions, ensuring optimal performance. Microbial inoculation is constantly and proactively adapted to improve extraction.

Endolith's technology may also play a role in the economic viability of mining lithium-rich clay deposits in America's Southwest, where the high carbonate content poses challenges for resource development. Endolith's solution involves selectively neutralizing problematic carbonates with microbiology prior to leaching, which reduces sulfuric acid use and enhances throughput and production.

Endolith's solutions offer a double dividend: reviving once-overlooked resources while reducing the environmental toll of traditional extraction. Less waste. Lower emissions. More metal.

Liz Dennett

Although the startup is still actively fundraising and specific technical details about rare earth element extraction have not been publicly disclosed, Endolith's approach has shown the capacity to extract a host of metals from low-grade or complex ores, with rare earths fitting the bill as notoriously difficult to separate and vitally important to try.

"Microbes don't just belong in mining: you can apply them to any process, whether it's recovering metals from e-waste, extracting rare earth elements from discarded batteries, or even remediating industrial wastewater where you're trying to extract more value out of waste material," said Endolith CEO Liz Dennett. "If we succeed, one day you'll walk through a copper mine that looks more like a biotech lab. And the waste piles? They'll be our next harvest. Endolith can be a fundamental component of the material value chain."