Here’s how engineered microbes could revolutionize mining

In our latest Lexicon episode, we sat down with Brandon Fields, Chief Science Officer and co-founder of Fieldstone Bio, to explore how synthetic biology, hyperspectral imaging, and artificial intelligence (AI) could transform how mining companies discover valuable mineral deposits. By combining biology with advanced imaging and AI, Fieldstone Bio is developing a novel way to identify mineral deposits, offering a glimpse into how living organisms could reshape the future of mining and critical mineral discovery. Also, subscribe to IE+ for premium insights and exclusive content! Nature already solved the problem The idea of using microbes to hunt for minerals might sound like science fiction, but, believe it or not, Fieldstone Bio is actually doing it. In fact, as it turns out, the process is not that tricky once you know what you’re doing. “Life figured out how to do a lot of things,” he said. “Let’s harness what we can and improve when we need to,” he added. Essentially, the company has found a kind of “hack” for something nature spent billions of years evolving. That being, ways to detect chemicals and metals in their surroundings. When you consider that some metals are essential for microbe survival, and others are potentially toxic, this makes complete sense. Why “reinvent the wheel,” in other words. “It’s really harnessing what life has evolved to do anyway and now suiting it to our purpose,” he told us. In a nutshell, the process involves modifying microbial reactions to metals to produce unique spectral signatures that hyperspectral cameras can detect. Simple on paper and, as it turns out, highly effective. As Fields explained, mining has always been driven by data. Exploration teams need to know exactly where valuable metals are located and in what concentrations before making expensive drilling decisions. “Measurements drive this industry. Every step of the mining lifecycle depends on knowing how much of these metals are in your materials,” he said. The problem is that today’s methods, while effective, are painfully slow. “The current technologies are just too slow,” he explained. “They’re waiting weeks to months to get this data back,” he added. Fieldstone’s goal is to change that by bringing measurements directly to the drill site. The process itself is deceptively simple. The microbes are sprayed onto freshly extracted drill cores. If target metals are present, the microbes activate their engineered sensing pathways and produce molecules that change how they reflect light. Those changes are then captured using hyperspectral cameras. Unlike ordinary cameras, which record red, green, and blue values for every pixel, hyperspectral cameras capture hundreds of individual wavelengths of light. “Every single pixel has hundreds of different colours,” he said. “We’re able to measure the reflectance at every single one of those pixels and create heat maps showing where the metals are,” he added. The result is a detailed map of metal distribution across an entire drill core. Pretty neat. Faster decisions, better economics Above all, perhaps the biggest advantage is not simply faster science. It is faster decision-making. Remote drilling campaigns are extraordinarily expensive. Fields explained that drilling a single hole can cost between $100,000 and $200,000, while exploration teams often operate hours from the nearest laboratory. “They have to decide where to drill next,” he told us. “If you could generate data the same day, you can tell the operators we found a deposit at this depth or this angle. Let’s move the drill this way,” he added. So, instead of drilling blindly while waiting for laboratory results, companies could continuously adjust their exploration strategy as new information becomes available. As you can imagine. that could dramatically reduce wasted drilling while speeding up resource definition. Built for the real world Many people assume sophisticated biological systems require large laboratories and expensive equipment. With Fieldstone Bio’s microbes, however, this no longer needs to be the case. “It’s essentially just liquid you can spray somewhere, and then the cameras are off-the-shelf systems,” he said. “We want a dried packet of cells that you could apply water to, spray onto a surface, and click a button to generate the data,” he added. So, rather than requiring trained molecular biologists on site, Fieldstone wants mining operators themselves to run the system with minimal training. As Fields points out, the challenge is no longer proving the science. “The bigger challenge is logistics. How do we package the cells? How do we make sure someone can use this without any training?” he told us. What about safety? Whenever engineered microbes enter the conversation, biosafety inevitably follows. Fortunately, the mining application offers some important advantages. Rather than releasing microbes into the environment, the sensing takes place inside contained systems using drill cores stored in enclosed boxes. “We can do this all in contained environments,” Fields explained. “We take that very seriously,” he added. The company is also carefully selecting microbial strains that are harmless to humans, plants, and surrounding ecosystems. The microbes only need to survive long enough to perform their sensing function before being safely destroyed. “They really don’t need to survive that long, to be honest,” he told us. Beyond mining Although mining is Fieldstone Bio’s main focus at present, Fields sees far broader opportunities ahead. Many of the same biological sensing systems could eventually monitor agricultural nutrients, detect environmental pollutants or help guide land remediation projects. “The same principle works outside mining altogether,” he said. “Cells have evolved ways to sense nutrients in agriculture, pollution and industrial chemicals,” he added. In this sense, the underlying platform remains the same; you just use different DNA to target different molecules. “I think the most surprising thing for people is how simple some of this stuff really is,” he said. “We’re taking things that life has evolved to do and repurposing them for our own systems,” he added. As Fields puts it, “It’s the simple things that are going to make the biggest impact early.” Get the latest in engineering, tech, space & science - delivered daily to your inbox.Christopher graduated from Cardiff University in 2004 with a Masters Degree in Geology. Since then, he has worked exclusively within the Built Environment, Occupational Health and Safety and Environmental Consultancy industries. He is a qualified and accredited Energy Consultant, Green Deal Assessor and Practitioner member of IEMA. Chris’s main interests range from Science and Engineering, Military and Ancient History to Politics and Philosophy.