Why does a silver necklace turn black? How to clean and prevent oxidation?

The main reasons for silver necklaces turning black are oxidation reactions and vulcanization. After the oxygen, sulfur, and humidity in the air come into contact with the silver surface, a black layer of silver sulfide (Ag2S) is formed, which is commonly seen as the phenomenon of "silver jewelry turning black". In addition, the sweat secreted by the human skin also contains certain sulfur components, which can cause silver jewelry to oxidize and change color faster when worn for a long time.

There are various methods to clean a silver necklace:

1. Use silver cloth: The specialized silver cloth can effectively remove the oxide layer on the surface of silver jewelry, and only need to be wiped hard to restore its luster.

2. Toothpaste cleaning method: Squeeze a small amount of toothpaste onto a soft bristled toothbrush, add water to moisten, gently brush the silver necklace, then rinse with water and wipe dry.

3. Lemon juice soaking: Soak the silver necklace in diluted lemon juice for about 5-10 minutes, taking care not to be too long to avoid excessive corrosion. Afterwards, rinse with clean water and thoroughly wipe dry.

4. Soap water cleaning: Prepare a bowl of warm water and add a few drops of mild dishwashing solution. Soak the silver necklace in it for about 15 minutes, then brush it with a soft bristled toothbrush, then rinse with clean water and wipe dry.

5. Cola cleaning method: Immerse the silver necklace in cola for about 12 hours, take it out, rinse it with clean water, and finally dry it with a soft cloth.

6. Professional cleaning agents: There are many professional cleaning agents available on the market for silver jewelry. Follow the instructions in the manual and rinse with clean water and wipe dry after cleaning.

The methods to prevent oxidation of silver necklaces include:

-Avoid long-term exposure to chemicals such as perfume, cosmetics, detergents, etc.

-When not worn for a long time, it should be stored in a sealed bag or moisture-proof box, and anti oxidation tablets or desiccants should be added.

-Regular cleaning and maintenance to reduce the erosion of dirt and sweat on the silver necklace.

-Clean and dry the silver jewelry promptly after wearing, keeping it dry.

-Silver jewelry with rhodium plating or other protective layers can be chosen to enhance its antioxidant capacity.