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1. Precious metals, the first universal equivalent, used in the manufacture of currency (now defunct), jewellery, and for preserving and increasing.
In addition to decorative, mainly for the power industry due to the activity of small, can be used as electrodes. Electrical connectors are usually gold-plated to prevent oxidation. Semiconductor chip Wire Welding (gold solder ball). Production of semiconductor devices usually takes the lead as internal.
Gold (K gold): refers to the gold and copper alloys. If 18 Gold (18 K gold), on behalf of the blunt containing the 18/24 and 6 / 24 of the copper alloy hardness than pure gold, widely used in gold ornaments and decorations.
Used in food, cakes will add some gold to highlight its value.
Games medals (gold medal)
2. Precious metals, in ancient times was used in the manufacture of currency (now only a little or commemorative coins), jewelry, and used in the manufacture of medals. In addition to decorative, mainly for the power industry due to the activity of small, can be used for wiring and other electrical conductors.