ox·i·da·tion | ˌäk-sə-ˈdā-shən
noun
A chemical process in which metals such as silver are blackened or tarnished as a reaction to sulfur and oxygen
Oxidation is a process by which metals blacken over time. This is common in silver and sterling silver because of the nature of the alloys that are commonly used for this type of jewelry. Because oxidation happens as a reaction to sulfur and oxygen, the latter of which is in permanent contact with jewelry, it is likely to happen over time. Factors that can contribute to oxidation include certain cleaning products or chemicals, excess moisture being applied to the jewelry, and exposure to high levels of acid in food or drink. Proper storage and cleaning is recommended to reduce the risk of premature oxidation of jewelry made from metals that are susceptible to it.
