Gold

Gold is highly valued because of its rarity, its attractiveness and its properties. It does not tarnish and can be easily shaped. It has been an international currency and symbol of wealth for thousands of years. Countries buy and store bars of gold, known as bullion, as part of their assets. Gold also has many ornamental and practical uses, which add to its value.

Many geological processes, such as the crystallisation of magma and the compression of rocks during metamorphism, produce hot water that dissolves metals and carries them through pores and fractures in rocks. As conditions change — for example, when the hot water cools — metal-bearing minerals crystallise and form hydrothermal ores.

Gold nuggets form deep underground, where hot fluids deposit gold and quartz in reefs. After millions of years of erosion these reefs are exposed, the quartz is broken down and the gold is washed out. Gold is inert so it remains in soil and streambeds, where it can be found – Eureka!

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MetalsMinerals from the Oxidised ZoneBroken Hill MineralsDundas MineralsBrowns Prospect Minerals
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