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Money That Grows On Trees
parvez1 submits this piece about a process that uses plants to soak up and accumulate contaminants - and gold - from near gold-mining sites. Then the plants are harvested for their metal content. The plants aren't bio-engineered - he's taking advantage of the natural tendency for certain plants to accumulate heavy metals.
The point isn't to make money out of this. They're doing it to clean up the pollution. It's nice that the gold can be sold to cover costs and provide some education, but it's great that they can get the mercury out of the soil.
This is not a sig
the reality is ... [gold] is not uncommon at all, why go through a complicated refining process to extract grams when the same amount of extraction energy would be better put to extracting tonnes
It's true that gold is not uncommon. My grandfather, a rockhound, used to observe that gold is very widely distributed around the world. He'd say: "Where is gold? Gold is where you find it."
What makes this plant-based reclamation process valuable is that it allows people who own low-grade deposits (e.g. mine tailings) to recover the gold. Say I'm a mine owner, and I've dug up all the gold on my land. I'm in the gold-mining business, but now my business will die, for lack of gold. Sure there's more gold in the world -- but can I afford to buy another mine? If not, I can at least use phyto-remediation to extract some gold from my otherwise useless mine tailings.
Besides, the main point of phyto-remediation to remove toxic metals from the environment. The process may not generate enough gold excite the envy of Croesus, but it does pay for the toxic-metal cleanup
-kgj
-kgj
Gold is still available as a currency. At this time, many countries produce gold bullion coins with a face value. Here in the USA we produce the Gold American Eagle series (started in 1986) of gold coins, available in four different sizes (1/10 ounce, 1/4 ounce, 1/2 ounce, and One Ounce). While they are technically produced just for investors and collectors, they do have a legal face value and you could actually spend them, if you didn't mind paying about 8.6 dollars for every dollar you spend (the one ounce piece has a face value of $50, and at todays market price runs about $430)
Sadburger
In 1933 Roosevelt made it illegal for a citizen to own gold. They were forced to turn over all their gold in exchange for paper money.
In 1975, it was made legal again to own gold bullion. But money it ain't.
American money is actually more akin to cloth than paper. It's really considered almost a fabric. That's why it doesn't rip up when you accidentally wash it in your laundry.
People have know about this "soaking up minerals from the ground" thing for a while. Forinstance, tobacco plants soak up polonium(uranium?) from the ground and that goes in to your lungs, as well as the rat poison and what ever the hell is in those things.
Bioremediation has been around for quite a while - it is a good idea in many situations.
There are a couple of things that really come out in the article is this - "First, he treats the contaminated soil with chemicals that break the gold down into water-soluble particles. Then he introduces the crops"
Gold and mercury in the soil is a pretty nasty amalgam - and gold being otherwise so *noble* - so I'm wondering how he's mobilizing it -
The article says the plants had purple leaves - "The plants he harvested had purple leaves because they contained gold nanoparticles" - again not totally breaking news - but he must be using something that can break the gold down *that* small (when there is a lot of gold in mercury, you can literally strain the gold out essentially with a filter like a cheesecloth - that is the technique that is being used by most miners of this sort in the first place.
Then they literally *cook* the amalgam covered pice of gold in a frying pan (though it could be done with nitric acid - or other things to remove the mercury from the surface)
In the process, a lot of mercury ends up spilled - and the residue from the *cook* is dense and fuming - and ends up not far away (like in the soil, the streams, or the miner's brain before too long) - Gold too small to picked up in the straining - In fact any microscale gold has been the subject of pretty intense interest because it is much more abundant than the occasional nugget -
Cyanide leaching is a very common process in areas where there is a lot of sunlight, since the cyanide can break down in holding pools - I highly doubt he would be using any cyanide - even if it could be shown to break down - it would most likely do very poorly on the plant side. Some halide - Bromides? Let's hope not. AuCl ion? - That's the most likely - or probably the most hoped for. There really aren't that many things that can dissolve gold - But there are actually quite a few ways to do what is being suggested with plants - here's one using geraniums.
Last term at the University of Oregon, we had the conceptual artist Mel Chin give a lecture on one of his projects entitled "Revival Field".
It's quite similar to what Chris Anderson is doing in Chile and Brazil. Funded by a $10,000 grant from the National Endowment for the Arts (NEA), Revival Field was the first experiment in the United States to use plants to absorb toxic metals from the soil. This launched the nation's burgeoning phytoremediation industry, which one business analyst predicts will be a $400 million dollar business by 2005.
but there is a more interesting tale from France. In the 1700's, France engaged in the Mississippi Scheme, a stock-jobbing plan based on expected returns from the Louisiana territories.
It had the classic effect, most recently repeated in the Internet boom and crash.
At the height of the Mississippi boom, the stock in the Mississippi corporation was a better currency than the franc, and was used as the national medium of exchange.
When it turned out that nothing was really happening in Mississippi at all, the paper money suddenly became worthless, and everyone tried to convert it into gold, then sneak that gold out of the country.
As a result, the king ordered that gold be illegal as a medium of exchange, and that ownership of more than a pittance was also grounds for confiscation.
When the U.S. prohibited the owning of large amounts of gold, it was entirely different... they wanted to maintain the stability of the metal itself, as the underpinning of the U.S. dollar, rather than suppressing gold ownership entirely.
Don't forget that when the U.S. was on the gold standard, having a dollar MEANT owning gold. That dollar was a certificate for that much from the federal reserve.