“They are acutely aware of what it takes to scale these technologies because they know the industry,” she says. “They’ll be your biggest supporters, but they’re going to be your biggest critics.” In addition to technical challenges, Rasner points out that venture-capital-backed biotechnology startups will struggle to deliver the quick returns their investors seek. Mining companies want lots of data before adopting a new process, which could take years of testing to compile. “This is not software,” Rasner says.   Nuton, a subsidiary of the mining giant Rio Tinto, is a good example. The company has been working for decades on a copper bioleaching process that uses a blend of archaea and bacteria strains, plus some chemical additives. But it started demonstrating the technology only late last year, at a mine in Arizona.  Nuton is testing an improved bioleaching process at Gunnison Copper’s Johnson Camp mine in Arizona.NUTON While Endolith and Nuton use naturally occurring microbes, the startup 1849 is hoping to achieve a bigger performance boost by genetically engineering microbes. “You can do what mining …