Sowing trees, Reaping solid minerals.

One night i was having my usual spell of insomnia and decided to see what was airing on a tech channel, i came across this phenom called "phyto mining" (thanks Insomnia!). In the stead of conventional mining
of solid minerals and rare earth elements with machines and lots of digging that could cause geographical rifts, scientists and engineers came up with an amazing solution that involves farming!. read more on my findings and see if there are other things that this concept could be used for (this is in the case of GOLD).
Money doesn't grow on trees — but gold might. An international team of scientists has found a way to grow and harvest gold from crop plants.
Called phytomining, the technique of finding gold uses plants to extract particles of the precious metal from soil. Some plants have the natural ability to take up through their roots and concentrate metals such as nickel, cadmium and zinc in their leaves and shoots. For years, scientists have explored the use of such plants, dubbed hyperaccumulators, for pollution removal.





But there are no known gold hyperaccumulators, because gold doesn't easily dissolve in water so plants have no natural way of taking the particles in through their roots.

"Under certain chemical conditions, gold solubility can be forced," said Chris Anderson, an environmental geochemist and gold phytomining expert at Massey University in New Zealand.

Fifteen years ago, it was possible to get mustard plants to suck up gold from chemically treated soil containing gold particles.
The technology works something like this: Find a fast-growing plant with a lot of aboveground leafy mass, such as mustard, sunflowers or tobacco. Plant the crop on soil that contains gold. The waste piles or tailings surrounding old gold mines are a good place to look. Conventional mining can't remove 100 percent of the gold from surrounding minerals so some gets wasted. Once the crops reach their full height, treat the soil with a chemical that makes gold soluble. When the plant transpires, pulling water up and out through tiny pores on its leaves, it will take up the gold water from the soil and accumulate it in its biomass. Then harvest.

Getting the gold into plants is the easy part. Getting the gold out has proved more difficult.

The gold found in plants are nanoparticles, so there may be great potential for the chemical industry, which uses gold nanoparticles as catalysts for chemical reactions.

Gold phytomining won't ever take the place of traditional gold mining, Anderson said. "The value of it is in the remediation of polluted mine sites.

However, some scientists say the environmental risks associated with growing gold itself may be too high. Cyanide and thiocyanate, the same hazardous chemicals used by mining companies to get gold to leach out of rock, must be used to dissolve gold particles in soil water.
culled from:  here and here