No relation to : Snowberry [a plant with similar name].
A rare non-native Eucalypt gum-tree likely to be found only in parks and large gardens. Like most, if not al Eucalypts, the leaves give off a smell of eucalyptus, which contains many highly volatile and flammable vapours. Whole forests of Gum Trees in Australia give off so much vapour on hot days that a blue haze fills the air above the forest. The fumes are dangerously inflammable and have been the cause of forest fires following some source of ignition.
The essential Oil of Eucalyptus (aka Eucalyptus Oil ) is used as a flavouring in pharmaceutical products and some medicinal toffees such as cough candy, lozenges, and is also used in ointments and inhalants to help with congested airways and breathing. It is safe at the low doses used, but is toxic at higher doses. Children in particular may suffer from severe poisoning at doses as low as 5mL of eucalyptus oil. It has a powerful woody smell and is used as a fragrance for cosmetics, soap bars and such like. Eucalyptus oil contains variable proportions of Phellandrene , Piperitone, Citral , Methyl Cinnamate, Geranyl Acetate, Limonene and Eucalyptol (aka 1,8-Cineole ), depending upon the type of Eucalyptus Tree it is derived from; there are over 300 different ones. Eucalyptus oils containing Eucalyptol are especially differentiated between those not containing it.
It is not surprising that Eucalyptus oil, containing so many ingredients, is anti-microbial, anti-bacterial and analgesic. Eucalyptus Oil containing Cineole is also an insect repellent and pesticide and has also been found to prevent the separation of ethanol and petrol in petrol pump fuel 'fortified' with ethanol. Eucalyptus Oil itself has a fairly high octane rating, but is too expensive to be used as a fuel.
Eucalyptus trees have very long roots that go down into the soil great distances, up to 100 feet in depth. For this reason, they have been found very useful in Australia for highlighting where un-known deposits of gold may lie buried. The dissolved gold is taken up (in minute quantities) by the roots, some of which is deposited in the timber itself, and some in the leaves.
Gold is not an essential element in any known plant, in fact it is highly deleterious to the plant. So the plants have devised a mechanism of secreting the gold safely away. They do this by incorporating it within the crystal structure of crystals of Calcite in the form of Calcium Oxalate. There it is out of harms way of the plant. Only minute quantities of gold are deposited in the leaves, a matter of a few 10's of parts per billion by weight. By themselves, the leaves are not worth mining for the gold contained within, it is far too dispersed to be of any value. But by analysing the leaves of many eucalyptus trees over a wide area gold rushers can ascertain where it might be profitable to dig deep for gold.
The gold is most likely dissolved by compounds containing cyanide within the plant. Certain Eucalyptus species are known to contain Prunasin and its steroisomer Sambunigrin and Amygdalin, all three are Cyanogenic Glycosides derived from PhenylAlanine . The latter, Amygdalin, a diglycoside, is rare found in only one species of Eucalyptus trees. The gold forms complexes with cyanide ions and is thus made soluble and transportable. The cyanide forms a dicyanoaurate complex, [Au(CN)2]-.
Jounama Snow Gum can take up Ferrocyanide by its roots and is proposed as a means of Phytoremediation of land contaminated by the cyanide used by certain mining operations in the recovery of gold.
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