Gold 999 is 99.9% gold, and 9999 is 99.99% gold. The digital symbol of gold represents purity, 999 is pure gold, and the purity of gold is 999 per thousand; 9999 is ten thousand gold, which means the purity of gold is 99900/ 10000, which means 9/ 10000.

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Precautions:

Some acid-base chemicals in daily life, such as perfume, hair gel, detergent and disinfectant, will change the color of gold. Therefore, before making up, cleaning, swimming and soaking in hot springs, you should take off the gold ornaments to avoid chemical reactions on the surface.

When gold jewelry meets cosmetics containing mercury and lead and has a chemical reaction, resulting in white spots on the surface, it should be taken to a gold and silver jewelry store for professional jewelry cleaning and maintenance.

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