Silver will turn black when it meets sweat, and black rust will be returned to gold, which will lead to discoloration of gold and decrease the quality of gold. It is also necessary to prevent the surface of gold ornaments from turning silver due to collision and friction.

Gold jewelry is jewelry made of gold. It has high investment value. Gold is considered as a precious metal with good physical properties. "Real gold is not afraid of fire" means that gold will not melt under the action of fire. It feels dense and heavy. Good toughness and ductility, good electrical conductivity.

Pure gold has a bright yellow part, but the color changes greatly after adding other metals, such as gold-copper alloy is dark red, and silver-containing alloy is light yellow or grayish white. Gold is easy to be ground into powder, which may also be the reason why gold is dispersed in nature, and pure gold jewelry is also easy to be worn and reduced in weight.

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When the gold ring and platinum ring are worn together, it is easy for them to rub against each other, which makes the surface of the gold ring locally white and platinum. Mercury corrodes the surface of gold, and first-class cosmetics often contain a small amount of lead and mercury. If gold jewelry often contacts cosmetics for a long time, it will cause white spots on the surface of jewelry. Therefore, when wearing gold jewelry, it is best to touch cosmetics less.

If this happens, go to a professional jewelry store to deal with it, and the white spots will be removed. Also avoid contact with vegetable juices containing chemical elements, such as mustard juice, cauliflower juice and fish scales.

References:

Baidu encyclopedia gold medal