Forget everything your parents ever taught you about managing your finances: Down under in Australia, scientists have found money growing on trees. Not paper money, of course, but eucalyptus leaves that are imbued with small amounts of pure gold.
These gilded leaves can help gold exploration companies discover new, underground gold deposits in difficult-to-reach locations.
The research, carried out by Melvyn Lintern at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and friends, discovered that trees in Australia and elsewhere in the world can be used to locate gold deposits that are more than 30 meters (100 feet) below the surface. Small amounts of gold are dissolved in water, which is then sucked up by tree roots. These particles eventually find themselves deposited in the leaves of the trees (the red dots in the image above).
Sadly, we’re talking about very small quantities of gold. Lintern says you would need to harvest 500 trees growing over a gold deposit to be able to make a gold ring. In scientific terms, we’re talking about a gold concentration of just 100 parts-per-billion in leaves, and about 50 ppb in twigs. To discover such tiny concentrations you can’t just use a conventional microscope: The Australian scientists had to use a synchrotron, a vast room-sized machine that uses X-rays to map the various elements present in a sample.
Still, despite the fact that money only grows on trees in minuscule amounts, the main takeaway here is that trees can be used to pinpoint underground gold deposits. As it stands, most gold is currently mined from outcrops, where gold-rich veins have been brought to the surface. As you can probably imagine, underground exploration — as with many new crude oil discoveries — is a lot more expensive and risky. If large gold deposits can be discovered just by analyzing a few leaves — and around 30% of the world’s gold reserves are believed to be under the Goldfields-Esperance region in Australia – then the price of gold could soon drop very quickly indeed. There’s no reason this technique can’t be applied to other important and valuable metals, such as copper and platinum, too.