An international team of researchers has figured out how one metal-gobbling bacterium, Cupriavidus metallidurans, manages to ingest toxic metallic compounds and still thrive, producing tiny gold nuggets as a side-effect.

Just like many other elements, gold can move through what's known as a biogeochemical cycle - being dissolved, shifted around, and eventually re-concentrated in Earth's sediment.

Microbes are involved in every step of this process, which has led scientists to wonder how they don't get poisoned by the highly toxic compounds that gold ions usually form in the soil.