1, bracelet is a kind of jewelry worn on the hand, which is in contact with human skin. People will sweat. If there is sweat, it will stick to the bracelet. The sulfur content in sweat is relatively high, which is the substance that causes the surface of silver jewelry to turn black.
2. Silver is a lively precious metal. Sulfur and oxides in the air will corrode silver bracelets to some extent. After the silver bracelet is corroded, the surface will generate oxides, so the color of the silver bracelet will turn black. Therefore, after the silver bracelet is worn or placed for a period of time, some tiny black spots or black films will appear. Then after waiting for a long time, the black spots and black films on the silver bracelet will slowly spread and begin to change color slowly, and the silver bracelet will even turn black seriously.
Extended data
Removal method of silver ornaments after blackening:
Spare materials: Coca-Cola, toothpaste, paper towels, towels and soft brushes.
1, soaked in Coca-Cola, because coke contains carbonic acid, you can remove silver sulfide, turn silver sulfide into silver lactate and dissolve it in liquid, thus achieving the effect of removing stains. The soaking time is 12 hour.
2. Take out the silver ornaments after soaking.
3. Wipe it with a clean towel.
4, you can also use toothpaste, squeeze a little toothpaste on the soft brush, and don't use too sharp tools when cleaning with toothpaste, otherwise it will wear the surface of silverware, but it will be more prone to oxidation and blackening.
5. Apply it on the surface of silverware, then wipe it with a soft toothbrush or a soft rag until the surface of silverware is shiny, and then rinse it with clear water.
6. Finally, wipe it with a clean wet towel.
Baidu encyclopedia-silver ornaments (ornaments)