Nature has its own version of gold leaves. It is not about leaves changing colors in autumn but real leaves with microdeposits of real gold. Australian scientists have reported that they found particles of the precious metal on the leaves of eucalyptus trees. While the amount of gold found will not be enough to cause people trading eucalyptus leaves, at least it is a good indicator where gold miners should start digging.
There have been reports before that traces of gold have been found in soils around eucalyptus trees and the same is true for its leaves. Some hypothesize that gold dusts must have been blown from nearby mines but now this phenomenon has been confirmed by the study published on the journal Nature Communications.
The team of scientists investigated eucalyptus trees in two locations in Australia, after ruling out possible contaminations from mining activities. Upon looking at x-ray of twigs, bark, and leaves of the trees, researchers found out that there are gold particles on them, with the highest concentrations on leaves, measuring as big as 8 microns. The amount of gold on the trees was not high enough to cause them harm.
"We've found a lot of the easy deposits in Australia and elsewhere in the world as well. Now we are trying to tackle finding these more difficult ones that are buried beneath tens of meters of river sediments and sand dunes. And the trees are providing us with a method to be able to do this," explained geochemist Dr. Melvyn Lintern, member of Commonwealth Scientific and Industrial Research Organization in Australia and lead author of the study, in an interview.
The roots of eucalyptus trees can grow deep into the ground in search for water and essential nutrients from the soil. It is through this process that the favorite trees of koala bears pilfer gold particles from deposits underneath the ground.
"We believe that the trees are acting like a hydraulic pump. They are bringing life-giving water from their roots, and in so doing, they are taking smaller dissolved gold particles up through the vascular system into the foliage," said Lintern.
The finding will allow gold miners to stretch their budget for exploration. Instead of just doing exploratory drilling, they can now do vegetation analysis to help find ore deposits underground.
As for people who are thinking of cutting down all eucalyptus trees to harvest the gold on them, that exercise might prove to be futile.
"We've done a calculation, and found that we need 500 trees growing over a gold deposit to have enough gold in the trees themselves to make a gold ring," said Lintern.
