Experts X-ray gold on eucalyptus leaves
23 Oct 2013
Researchers from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) have discovered that eucalyptus trees in Western Australia are drawing up gold particles from the earth and depositing it on their leaves and branches.
CSIRO geochemist Dr Mel Lintern said: “The eucalypt acts as a hydraulic pump - its roots extend tens of metres into the ground and draw up water containing the gold. As the gold is likely to be toxic to the plant, it’s moved to the leaves and branches where it can be released or shed to the ground.”
The “nuggets”, which measure around one-fifth the diameter of human hair could provide researchers with an opportunity for extended mineral exploration.
The phenomenon could indicate gold ore deposits buried up to tens of metres underground and under sediments that are up to 60 million years old.
“By sampling and analysing vegetation for traces of minerals, we may get an idea of what’s happening below the surface without the need to drill. It’s a more targeted way of searching for minerals that reduces costs and impact on the environment,” Lintern said.
Using CSIRO’s Maia detector for X-ray elemental imaging at the Australian Synchrotron, the research team was able to locate and see the gold in the leaves.
The Synchrotron produced images depicting the gold, which would otherwise have been untraceable.
Dr David Paterson, principal scientist at the Synchrotron, said: “Our advanced X-ray imaging enabled the researchers to examine the leaves and produce clear images of the traces of gold and other metals, nestled within their structure.”
Outcome of the study was published in the journal Nature Communications.
