This is a normal situation, because silver is particularly active in chemistry, and it is particularly prone to oxidation when exposed to air, especially after being used. The silver health cup will turn yellow or even black after being oxidized, so we need to maintain it in time and clean it irregularly when using it.

There are several cleaning methods for silver cups after oxidation and yellowing:

First, the soft toothbrush should be scrubbed with toothpaste. The soft toothbrush here is the kind that can rotate 270 degrees, because it is difficult for ordinary toothbrushes to brush to the end. Other silver utensils, such as silver tea sets and tableware, can also be cleaned in this way.

The second is to pour the cola into a silver cup (the silver cup needs to be filled) and leave it for about 12 hours. If 12 hour has not achieved the desired effect, continue to soak.

Third, add baking soda powder to clear water, and then wipe the silver cup with a soft rag dipped in water.

Fourth, ultrasonic cleaning method: this cleaning method also needs a professional machine-ultrasonic cleaning instrument. The principle is the same as cleaning teeth. Shake off the yellow and black part of the silver liner surface with ultrasonic wave.

It is normal for the inner container of the silver cup to turn yellow, which just shows that your silver cup contains high purity, so don't worry.

I hope it helps you. Thank you.