Scientists finally found a way to make pure gold. Weil… But it is a good science story.
A newly discovered bacteria produces pure gold from a toxic acid. Cupriavidus metallidurans eats toxic gold chloride and separates the chloride from the gold. Ta Ta!! 99.9% (24 carat) gold.
Michigan State University
Accoding to Kashefi, they are doing "microbial alchemy" by "something that has no value into a solid [in fact, it the toxic material they use does cost money. Less than gold, but still plenty], precious metal that's valuable."
The bacteria is incredibly resistant to this toxic element. In fact, it's 25 times stronger than previously thought. The researchers' compact factory—which they named The Great Work of the Metal Lover—holds the bacteria as they feed it the gold chloride. In about a week, the bacteria does its job, processing all that junk into the precious metal—a process they believe happens regularly in nature.
So yes, basically, Cupriavidus metallidurans can eat toxins and poop out gold nuggets.
It seems that medieval alchemists were looking for the Philosopher's Stone—the magic element that could turn lead to gold—in the wrong place. It's not a mineral. It's a bug.