Published: 12 Mar 2018
Nugget producing bacteria
Gold begins its journey underground and it owes it all to something pretty unusual – bacteria. Let’s back up for a minute. Deep in the bowels of the earth, fiery heat and high-pressure levels combine to form primary gold. This gold makes it way into the soil and waterbodies through biogeochemical weathering. On the way to the great ocean, a certain kind of micro-organism encounters the primary gold, dissolves it, frees it from silver particles and then helps it re-concentrate into solid gold nuggets. It is this micro-organism, or rather a group of many of them, that scientists from the University of Adelaide are clinking glasses over.
Unofficially called ‘nugget producing bacteria,’ these organisms have always been involved in the process of forming gold under the Earth’s surface. It is just now, that scientists have managed to put a time period to the process. Thanks to the bacteria, it only takes a couple of decades for gold to go through its formation cycle and according to scientists, that’s just “a blink of an eye” in geological time. This discovery has the potential to revolutionise everything we know about gold mining. It can make it economically viable, speedy as well as more efficient.
There are all sorts of wonderful things the bacteria can do. Scientists are discovering that it could be just the ticket to develop innovative processing techniques, help discover hidden gold deposits and improve ore processing. What’s more, the bacteria could be used to check how authentic archeologic or ancient gold artefacts are, effectively weeding out copies or frauds. Research on the role of nugget-producing bacteria has been underway for over ten years now, primarily by scientists from the University of Adelaide. Journal Chemical Geology reports that a dedicated team studied numerous gold grains under high resolution electron-microscopy to arrive at their conclusions. Their ongoing efforts spell hope for anyone interested in the metal. After all, there is no such thing as too much gold.