These chemicals can react with metals in the jewellery. A really predominant example is if you have met someone who wears copper jewellery, it is very common that the person will have a greenish stain on their skin. This is as a result of the chemicals in their perspiration reacting with the copper and the resulting chemical reaction stains skin.
It is very important to keep aware that every jewellery manufacturer will have a recipe mix of metals that are used to make their jewellery.
To use a food analogy, we have many different recipes to make a cake, just as there are many different recipes to make jewellery alloys. The only thing standard in the jewellery alloys is the percentage of gold that is used. Follow this link to see our blog post on gold colours and gold carat types.
So not only can the different metals react with the perspiration from our skin, and the chemicals in soaps and body lotions, but also with the different metal types within the jewellery itself which can flake off and leave a black mark on the skin.
To try to minimize marking of your skin due to chemical reactions, we always advise that you take off your ring before washing your hands or applying lotions or hand sanitizer. And it's best to take it off before you go swimming too.
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