The blackening of gold jewelry can not be separated from people's sweat, and the color change of jewelry in summer is more than that in winter. This is because the metabolism of the human body is fast in summer, and about 1% of the sweat discharged is wastes in the human body, such as chlorine-containing substances, urea, ammonia and so on.

When these elements come into contact with silver or copper in gold jewelry, silver chloride and copper sulfide will be generated, and associated dark black chemical salts will be generated, leaving black spots on the skin, thus making the gold necklace dull.

Extended data:

Maintenance of gold jewelry:

1. First, store gold jewelry in jewelry boxes or suede, and get into the habit of not throwing it with other jewelry after wearing it to prevent mutual scratches.

2. Put the precious ornaments in a safe place and buy enough insurance. If you don't know much about the value of your jewelry, please take it to the local jeweler for evaluation.

3. Wash gold ornaments regularly. This can ensure that jewelry presents the best luster and lasts longer. The cleaning method of gold ornaments is the same as other precious ornaments; Use a jewelry cleaner sold in the market, or soak it in soap and water solution, and then gently wipe it with a soft cloth.

4. For the gold jewelry alum inlaid with precious stones, it needs to be cleaned once every six months. Jewelry is adjusted, resized, polished and cleaned by qualified jewelers. In order to maintain your gold professionally, first of all, make sure that the jeweler has a trained gold assembler.

If there are scratches visible to the naked eye, please take the gold jewelry to a qualified jeweler for polishing. All precious metals may leave scratches, and gold is no exception. But there will be a natural oxide layer on the surface of gold, so many people may prefer the surface that has just been polished. If this happens, please give your platinum jewelry to a qualified jeweler and let them re-polish it to produce an extremely bright effect.

6. Please don't wear gold ornaments when doing housework cleaning, gardening and other types of heavy work or physical activities. Because women wearing gold ornaments are easy to contact with bleaching or irritating chemicals when doing housework. Although chemicals will not damage gold, they may discolor diamonds or precious stones.

7. It is best not to wear or reduce the time of wearing gold jewelry in summer, because frequent application or sweat soaking will make blonde hair black, and some women will also cause itchy skin or allergic symptoms.

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