925 Sterling Silver tends to eventually oxidise and this process will occur prematurely if the metal comes into contact with perfume, saltwater, sulphur, lotion, hairspray or chlorine.
The pH level of one’s skin, which varies from person to person, can also affect how quickly oxidation takes place, which is why it does not fall within manufacturing defects.
Oxidation can be easily resolved by cleaning the silver using a silver specific polishing cloth.
Yellow gold can be cleaned using a gold specific polishing cloth. Otherwise by washing the jewelry in lukewarm water then gently cleaning it with a soft brush and finally drying it in a non-abrasive cloth.
Gemstones and Pearls
Gemstones such as sapphires and diamonds can be cleaned by washing the items in lukewarm water then gently cleaning them with a soft brush and drying them in a non-abrasive cloth. Pearls on the other hand are porous which means that they are even more sensitive to chemicals. They can be refreshed by gently cleaning them with a dampened cloth.
As previously stated do not expose gemstones to sources of intense heat since temperature change can irreversibly ruin them.