October 24th, 2013 by

Eucalyptus trees like this one produce gold-flecked leaves when they grow over a gold deposit.

Eucalyptus tree. Credit: Justin Ennis

Money does not grow on trees, but researchers from Australia contend that gold just might. In a recent study published in Nature Communications, these scientists wrote that traces of gold have been found in the leaves of Eucalyptus trees. These traces of gold are miniscule — so small, in fact, that it would take more than 500 trees to provide enough gold for a single ring. So, what can these deposits be used for, if not for jewelry? Scientists say that these gold-infused leaves can indicate the presence of a gold deposit, which offers a new method for determining the location of the precious metal in hard-to-access areas. Many of the easier-to-reach deposits of gold in Australia and around the world have already been located, but these trees may provide clues to more secluded deposit locations.

Dr. Mel Lintern, a geochemist, explained that the current hypothesis is 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.” Identifying gold deposits in this way presents two huge potential benefits, both economic and environmental. The use of this technique could limit exploratory drilling, relieving some expense while also minimizing damage to the environment, as only small samples are taken to determine the location of gold deposits. The researchers hope that this method could also be used to find other minerals, drastically reducing the amount of exploratory drilling to the great benefit of the environment.