Some people say that you should not take Au (gold), Ag (silver), Pt (platinum) and other jewelry to soak in hot springs or swim in the sea. The reason for this is that these people think that seawater has acid, alkali and salt, and hot springs in different places contain different minerals. If the color of the jewelry is not enough, other components in the jewelry may react chemically.
If the jewelry bought in a regular jewelry store is pure gold (with a gold content of more than 99%) or pure gold (with a gold content of more than 999%), you don't have to worry too much, because the jewelry contains very few ingredients (less than 1%), even if there is a chemical reaction, the worst case is nothing more than a discount on the gloss of the jewelry. If you buy something with insufficient color, the jewelry may turn black. But in either case, you can go to the jewelry store to clean it and restore the luster of the jewelry. However, I still suggest that 18K (with a gold content of 75%) and jewelry with a gold content of less than 900% should not be taken to these two places. After all, there is a real chemical reaction that can turn black. But if the color is so low, it will be a little troublesome in some cases. I won't say anything. Handwriting and typing are wordy.