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Five years after President Donald Trump signaled his support for extracting metals from the moon, his new administration is seeking to satisfy the United States’ hunger for critical minerals by encouraging mining under the polar ice caps, amid warzones, and at the bottom of the ocean.
A breakthrough by a startup backed by two of the world’s biggest mining companies points to a different path to obtaining the metals needed for manufacturing next-generation energy and defense technologies: Microbes.
Last week, the Denver-based company Endolith announced the completion of tests on whether its mix of genetically modified microbes could extract significant amounts of copper from the type of low-grade, hard-to-process ores left over in mining waste that make up 70 percent of the world’s known reserves of the metal.
The results “outperformed conventional approaches to low-grade heap leaching and revealed new value in mineralized waste previously considered uneconomic to process.”
In other words, the company said it proved its “microscopic miners” are “remarkably good at extracting metals that conventional chemistry leaves behind,” Endolith CEO Liz Dennett told me, noting that her company was prepared to deploy its microbes at scale.
“We don’t need to mine the moon or venture 20,000 leagues under the sea to solve our copper shortage,” she told me over email. “The microbes have been doing this work for billions of years, we’re just finally paying attention.”
The US federal government is just starting to pump money into researching the use of microbes for mining. The Australian mining behemoth BHP provided Endolith with funding for testing and site-matched ore samples through its in-house innovation program. The London-based metals giant Rio Tinto, meanwhile, backed the Founders Factory startup accelerator that helped Endolith get started. Still, neither company has made a formal investment in Endolith.
Here’s how Endolith’s process works: First, the company analyzes the ore and the native microbes—which include both bacteria and archaea, the tinier single-celled organisms—at each site to understand the baseline conditions. Then, using a microbial library and genomic techniques, its researchers select and adapt strains that are best suited to the specific mineralogy and conditions of the site.
Once that’s established, Endolith grows the optimized microbes in portable bioreactors, ensuring that the microbes are fresh and consistent with the location. Finally, the company adds the microbes via liquid sprinkled or dripped onto heaps of wasted dirt at the mine and continuously monitors the activity to make real-time adjustments to maximize how much copper the microbes are recovering.
“We’re creating a new industrial paradigm at the intersection of biology and mining.”
“We’re creating a new industrial paradigm at the intersection of biology and mining,” said Dennett, who earned a Ph.D in geosciences at the University of Wisconsin-Madison and went on to work at NASA’s astrobiology program and run data architecture for Amazon Web Services before founding Endolith. “Our goal is simple: reshape supply chains for the most important technology transitions of our lifetime.”
Extracting metals with microbes is nothing new. The process of using microbes to convert copper ions in liquid into metal through calcification dates back more than 2,000 years. While the actual biological function wasn’t yet understood, Han dynasty prince Liu An described using water to concentrate copper as far back as 120 BCE, a method Chinese scientists later put into practice in 1086 under the Northern Song dynasty.
It wasn’t until the mid-20th century that miners found convincing evidence showing “that microbes were active participants in leaching copper and some other metals from ores,” according to a 2003 paper from the Rensselaer Polytechnic Institute.
In recent years, scientists have ratcheted up research into different kinds of bacteria that could be used to produce rare earth metals. But there’s been little commercial activity outside laboratories.
Endolith’s test results are a “significant and potentially meaningful step forward in the field,” said Patricio Martínez Bellange, the director of biomining at Universidad Andrés Bello’s Center for Sustainable Biotechnology in Chile.
“While further validation is necessary, Endolith’s reported results represent a promising advancement in unlocking significant copper resources from low-grade ores in a potentially more sustainable manner,” he told me in a LinkedIn message after reviewing the company’s announcement. “This could indeed be a meaningful milestone in the quest for a more secure and environmentally responsible supply of critical minerals.”
Still, he cautioned that different ore types, “the long-term stability of the microbial cultures under industrial conditions, and the overall economics at scale will need to be thoroughly evaluated.”
Competition with the naturally-occurring microbes at mines represents “the next challenge” to “fully scaling up this process in the field,” said Buz Barstow, an associate professor of biological engineering at Cornell University.
If Endolith’s real-time monitoring “can solve this problem,” then they will truly be onto something,” said Barstow, who reviewed the company’s announcement for this newsletter.
But one solution can beget another problem. “If they do solve this problem,” he said, “then it creates the new problem of containment of these genetically engineered microbes.”
These are still the early days of researching biomining, Barstow said. National funding for researching metal-mining microbes has been scarce.
That was starting to turn around. In 2023, the National Science Foundation opened the door to financing research into the nascent field. Barstow said he and colleagues proposed a project called the Microbe-Mineral Atlas, consisting of 22 principal investigators at 11 universities in four countries—the US, Britain, Japan, and Canada—that would discover new knowledge about how microbes interact with minerals and metals and how they could be engineered for biomining.
The British, Japanese, and Canadian funders rejected the project as “too ambitious,” he said. But the Biden administration’s National Science Foundation “took a risk on the US part of the team, and gave us a small down payment on the funding we asked for.”
Since January, Barstow said, his team has been working on sampling microbes from “geologically unusual environments, trying to figure out new genes that control mineral and metal interactions.”
But his hopes are dimming now with the Trump administration slashing all kinds of federal grants.
“With funding cuts from the government,” Barstow said, “this type of work is in danger of never getting off the ground.”
This post has been syndicated from Mother Jones, where it was published under this address.