Gold,
Au on the periodic table of elements and the shiny metal that holds her diamond
in place on her delicate little finger. Gold has been used to back our
financial system, it has been used as a luxury item in trade for millennia, in
more recent years it has been discovered to have medicinal properties! (You can
read more about that in my past blog entry about Gold Nanoparticles here.)But the reality of gold is that like
many other minerals and natural resources, the quantity of it is finite,
meaning eventually, we aren’t going to find anymore.
For
a long time it seemed that concern was quickly coming upon us with agencies
like Cash 4 Gold springing up on every corner and commercials for jewelry
trade-ins airing day in day out, it seemed everyone was desperate to get their
hands on this miracle metal. But that may now be a thing of the past…for the
time being anyway.
Today
at To Infinity…and In Theory we’re going to talk about the prospects of
prospecting gold from Eucalyptus trees. The golden goose may soon become the
golden Koala. Let’s start by heading over to Australia to see exactly how
scientists are harvesting their bumper crops of money trees.
I Got a Golden Ticket!
…Oh Wait, Just a Leaf
Know
what that is? That’s the cross section of a Eucalyptus leaf infused with gold
particles. The question is, how in the heck did they get there? It’s quite
simple really, and gold isn’t the only precious metal that gets pulled into
foliage. The answer lies in the base of the tree where it all begins. The
roots.
In
the case of the Eucalyptus trees we’re talking about right now it turns out
there was a giant gold deposit about 100 feet below the surface. What happened
is some of the gold was flaking off and working its way up through the soil. At
the same time as the tree grew the roots were reaching deeper down into the
crust. When the root system of the tree meets the flaking gold particles in the
soil it was sucked in along with nutrients and, like fat in the human body, it
became lodged in the leaves of the tree.
“Finding
such high concentrations of gold in the foliage of this tree growing over a
gold deposit buried beneath 35 meters of weathered rock was a complete
surprise,” said Melvyn Lintern, a geochemist at Australia’s Commonwealth
Scientific and Industrial Research Organization (CSIRO). But what a pleasant
surprise this was, and one that opened a door to a new way of prospecting.
Taking samples of leaves was much more eco-friendly than the other methods of
searching for deposits of gold.
But
what you may find most amazing of all is this discovery isn’t brand new. Like
everything else it seems to take us way longer than we should to adopt a new
way of thinking. This method of prospecting has been around for centuries! So
why wasn’t it being employed before now?
There Be Gold in Them
Hills…Err, Trees
The
process of using flora to search for mineral and ore deposits is known as
Biogeochemical or Geobotanical Prospecting. These are two very different
processes and fields of study that we will discuss in further detail later. But
first, let’s talk about the early days of these techniques.
Turns
out the Chinese invented this method of ore hunting in 5th century
B.C. when they began noticing that certain plants grew only in areas where
there were deposits. Perhaps the most notable of these specialized plants is
the Copper Flower, which grows only over copper and nickel deposits in Africa.
See
it started as an agricultural thing. They were looking for suitable areas of
land to grow their crops and feed. Sometimes though, the plants would not take
to the soil and just die. When all other possibilities (poor farming,
environmental weather factors, predation) were rooted out they called in the
scientists. That was when they discovered something that surprised them.
Underneath a lot of the areas where crops wouldn’t grow were large mineral and
precious ore deposits.
This
warranted more observation, something the people of China were (and still are)
very good at. They noticed that in areas where jade deposits were located, the
branches of trees would droop significantly. What was happening is pieces of
the mineral were being pulled up through the root system and weighing the
branches down. They also began to note that when certain flowers were burned
the ash was high in contents of Zinc, some even going so far as being 16%!
Thus, Geobotanical Prospecting was born.
They
began noticing that the stalks of some plants were yellow in certain varieties
instead of green. This became an indicator that copper was abundant below. If
the leaves of some plants were green but the stalks were red it meant there was
a lead deposit beneath it. Considering these were the days before portable
electronics like metal detectors, this new no-fail method seemed to be working
pretty well.
However
it wasn’t exactly a “no-fail” method as it didn’t involve the scientific
process and it’s likely that some of the research in modern times would be
discredited. After all, it wasn’t until 1421 that a Chinese author proved
certain metals could be extracted from these plants in the book Precious Secrets of the Realm of the Keng
and Hsin (symbols of metals and minerals). But all things considered, this
was still a unique and quite possibly a lucrative method for would-be
prospectors the world over.
So
why are we just hearing about this now? While this method has been known about
since ancient Chinese times it wasn’t widely researched or even written about
in the West until around the 18th century. Why? Because gold was
still readily available at the time all over the world trapped within the Earth
and searching for gold deposits wasn’t quite the difficult task it is today.
But as reserves began drying up it was time to look for new ways to skin the
proverbial cat.
The Western Seeds of
Geobotany Take Root
North
America didn’t really get into the Geobotanical or biogeochemical fields until
just a few decades ago. However you could say biogeochemistry began to rear its
head around the mid-nineteenth century. In 1841 Russian geologist Karpinsky
proposed that when drawing a parallel between plant life and the geological
substrate the flora took root in that the entire species of that plant needed
to be taken into account as a whole. Let me give an example.
Say
you have a green three leaf clover growing in your backyard. Since there is no
mineral deposit underneath it, that clover grows naturally, normal coloration
and no deformities. That same species of clover is found growing wild in
someone else’s backyard in Japan. After testing it, everyone is satisfied it is
the same species, however, this clover is red. It’s later discovered a large
copper deposit is underneath that patch of clovers and when the test Japanese
clovers are burned the ash content is high in copper content.
While
green clovers and red clovers could exist the above is just a hypothetical
example to put it in perspective.
Now
we flash forward to the 1920s, still in Russia. Following the example of
Karpinksy and his proposal, a scientist named S.P. Aleksandrov noticed that
plants outside of an ore zone were high in concentrations of Vanadium, Radium,
and Uranium when their ashes were analyzed. Guess what they found beneath the
plants? I’ll give you a hint, it was yellow-cake and it wasn’t a Twinkie.
Soon
after this discovery the first Biogeochemistry lab was constructed in the USSR
and the search for ore, minerals, and precious metals began by analyzing the
flora. America wouldn’t make a contribution to this field until the late
1980’s.
It’s
important to note that there are two key differences between Biogeochemistry
and Geobotanical prospecting. Biogeochemical prospecting involves digging into
the relationship of plants and animals to the chemical structure of their
environment. In other words, the same species of tree in one area of the world
may have different chemicals or elements trapped within it due to the
composition of its soil.
Geobotany
is the study of plants and their relationship to the environment. It studies
the effect has on the environment, not the effect the environment has on the
plant. Only time will tell if either of these methods prove to be fruitful for
further exploration in prospecting. One thing however is quite certain. Money
may not grow on trees. But it
certainly can grow in them.
-
Ryan
Sanders
Thanks for reading! Sorry I haven’t
posted in a few days, there’s a wicked flu going around and I’ve been laid up
in bed recovering but the blog is back now! If you would like to know more
about any of the things we talked about above today you can by following any of
the links available below. Happy learning everyone!
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