Gold Mining Bacteria

Anonymous 49'er writes "Nature is reporting that bacteria found in Australian gold mines are capable of extruding tiny invisible 'secondary grains' from soil and alluvial systems. From the article: "Potential applications -- from sensing the bacteria as a way to look for gold mines, to using them to help make industrially useful particles of gold -- may be some way off. But Southam is keen to exploit the bacteria's natural trick. 'I want to make a gold nugget one day,' he says. 'Gold nuggets grow in nature, so why shouldn't I be able to make one?'"

Re:Gold nuggets growing wildly...

[ozmanjusri]

Concentrations of gold don't seem to fit a natural process

Most of the gold in the world is in archaean deposits or was transported from archaean sources by alluvial processes. In these deposits, the gold was dissolved from basalt rocks by superheated water, then precipitated out into cracks and fissures as the water got too cold to maintain the solution. http://en.wikipedia.org/wiki/Ore_genesis#Gold [wikipedia.org]

The use of bacteria in mining is nothing new though. We've been using "bug leach" techniques in Australian mines for more than a decade. http://www.indmetlab.com.au/equipment/bio_metallur gy.php [indmetlab.com.au] The main novelty of this species of bacteria is that it produces metallic gold instead of gold compounds. Given the relative ease of precipitating gold from solution, I'm not sure if it'll be enough of an advance to be worth using.

from the 70s/80's

[WindBourne]

back in late 70's/early 80's, I got my first degree in Microbio. so I paid attention to this. Back then, this was being explored (as well as doing it for leeching of other metals esp. copper, uranium, etc). The idea was to lower the energy needs, lower the environmental impact, and finally to be able to selectively go through garbage dumps and old leech fields. It actually makes great sense.

What bothers me about this is that we gave it up as oil prices were pushed down. We should have pushed it forward then.