Okay, this is awesome and really makes me wish I would have gone into biology. An article I recently read showed what could revolutionize the gold mining industry. Apparently there is a micro gold miner out there capable of recovering gold which would otherwise be lost in the mining process. We all know that most gold found is very, very fine gold. Nuggets and pickers make up a small percentage of the gold ever found. In fact the largest gold mine in the United States is the Carlin Trend mining district. According to Wikipedia, it “…has since produced more gold than any other mining district in the United States, ” with over 50,000,000 troy ounces as of 2002 and still going. This mine uses an open pit mining process called “cyanide heap leeching” that involves using cyanide to leech gold from earth and crushed rock. It doesn’t take a scientist to tell you that is not the most environmentally friendly way to retrieve gold.
A new discovery may have uncovered a way to produce gold from gold ions (which is about as small as you can get in terms of the gold’s size) using, guess what? Bacteria. In an article from The Scientist, a magazine for life scientists, called Microbial Metallurgyrecently released an article. Below is an excerpt of their findings.
The process uses bacteria to form gold nuggets out of gold ions. To the bacteria the gold is simply waste, which it concentrates much like how an ant forms a mound. This is enough to make any gold prospector want to start a bacteria farm!
Meet the bacterium that pulls gold ions out of solution and forms tiny nuggets of the precious metal.
Researchers have found that a bacterial species stimulates the formation of gold particles in its environment as a way to survive in solutions containing toxic gold ions. The bacterium, Delftia acidovarans, secretes a compound dubbed delftibactin that precipitates gold ions, causing them to clump into nuggets.
Canadian researchers, who published their work in Nature Chemical Biology this week (February 3), grew the bacteria in the presence of gold ions and found that gold nanoparticles began accumulating in the solution. They also identified the genes responsible for producing delftibactin and shuttling it outside of the bacterial cells.
Frank Reith, an environmental microbiologist at the University of Adelaide in Australia who was not involved in the study, told Nature that the discovery could in the future help clean up toxic gold mine waste water, while recovering more gold from the slurry. “The idea could be to use a bacterium or metabolite to seed these waste-drop piles, leave them standing for years, and see if bigger particles form,” he said.