For centuries, miners and prospectors had to pan for gold in streams, or look about on the surface, to find traces of the glittery rock that might lead to big scores underground.
Now a new technique, courtesy of Mother Nature, may prove to be even more fruitful.
As reported in the Economist:
“Trees offer an alternative that is finally bearing fruit …. The idea has been around since the 1940s but, until now, never practical. Some trees have roots that reach deep underground, drawing up water and, along with it, tiny quantities of minerals that end up distributed throughout the tree. In this way, even lofty leaves bear traces of what lies far beneath. The quantities are minuscule. In areas where there is no gold, leaves may have a background level of 0.15 parts per billion (ppb) of gold; on gold-rich sites that can rise to 4ppb.”
The article notes that using trees to find gold isn’t exactly easy. This is because “sampling” arbor leaves for gold is done differently depending upon which species you are looking at. In Australia, where the first testing is taking place, “acacia” is the tree of choice because its roots go deep into the ground. But even with acacia, there are over 1000 varieties — and each needs to be assessed a little bit differently because of how it uniquely stores gold in its foliage.
Australia’s National Science Agency has reviewed the process and says its studies confirm that biogeochemical prospecting (the technical name of this process) closely tallies with surface and groundwater analyses. This is a positive sign. Even better news, however, is that a firm called Marmota actually undertook a real world field-test of this technique and, voila, it worked!
To read the full story in the Economist, click here.