Reasons for the blackening of gold jewelry Waste and harmful substances discharged by human body, such as chlorinated substances, lactic acid, urea and ammonia, will react with silver and copper in gold jewelry to produce dark black silver chloride and copper sulfide. This chemical salt sometimes falls from gold jewelry, and also pollutes the wearer's skin, leaving a very obvious black stain.
Daily wear or environmental factors may make gold jewelry lose its bright color. For example, in dry areas, the air contains a lot of fine dust, which will form a kind of human sandpaper after being polluted by human body, which can grind gold jewelry into extremely fine debris and appear local black stains. It is worth mentioning that talcum powder or moisturizer also contains similar particles, which will also overshadow the above-mentioned gold jewelry.
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Precautions:
1, avoid contact with perfume, bleach, cosmetics and other chemicals during daily wearing of gold jewelry. In order to prevent chemical action, gold is discolored.
2. Gold ornaments are easy to react with mercury, silverware and lead. , making gold ornaments appear white spots. Therefore, contact with these metals should be avoided when wearing and storing.
3, gold jewelry should try to avoid being put together with other jewelry, especially diamonds, which are scratched because of their different hardness, and should be stored separately in the jewelry box.
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