Why does gold jewelry change color and why?

Why does gold jewelry change color and why? The discoloration or fading of gold jewelry is closely related to human sweat. 99% of human sweat is water, and the other 1% is waste and harmful substances in the human body, such as chlorinated substances, lactic acid, urea, ammonia, etc. 　　 Why does gold jewelry change color and why?　　 The discoloration or fading of gold jewelry is closely related to human sweat. 99% of human sweat is water, and about 1% is waste and harmful substances in the human body, such as chlorinated substances, lactic acid, urea and ammonia. When these substances come into contact with silver and copper in gold jewelry, they will have a chemical reaction to produce silver chloride and copper sulfide, and present dark black chemical salts. This chemical salt often falls from gold jewelry, polluting the wearer's skin, leaving a very obvious black stain on the skin.　　　　 Now cosmetics has also become one of the indispensable'characters' in people's lives. If it is applied to the skin where gold jewelry is worn, it will undoubtedly provide opportunities for cosmetics containing chemical substances and gold jewelry that are most afraid of chemical substances. Some cosmetics also contain some fine hard particles, which can form another type of dirt and wear gold jewelry. Geographical environmental factors may also make gold jewelry lose its bright color. For example, in a drier area, the air contains more original fine dust, which will form a kind of 'human sandpaper' when it is contaminated with the human body, which can abrade the gold jewelry to extremely fine debris and cause local black stains. It is worth mentioning that talcum powder or moisturizer also contains similar particles, which will overshadow gold jewelry as mentioned above.　　　　 treatment method: scrub with soapy water mixed with a little alcohol, rinse and dry. The above is the information about buying gold jewelry summarized by the author for you. The information comes from the Internet. If there is something wrong, please understand. If you need knowledge and understanding of gold jewelry processing, please pay attention to the official website of jewelry inlay. Jewelry inlay is waiting for your inquiry !