Pure Gold

gold nugget

While gold does not readily combine chemically with other substances, it is often diluted or "watered down" by impurities of other metals such as silver, copper or mercury (in the form of mixtures called alloys).

The term "carat" is used to describe the purity of gold and is based on a total of 24 parts. Pure gold (100% gold and nothing else) is known as 24 carat. In 18 carat gold, for example, 18 of the 24 parts are gold and the remaining 6 parts are another metal, such as silver or copper.

The properties of pure gold discussed above are obviously altered when you add other metals. For example 24 carat gold is probably too soft to make long lasting jewellery so 18 or 9 carat gold is used as it is harder.

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