Tarnish

To tarnish means to lose luster or become discolored, especially as a result of exposure to air or moisture.

Part of speech: verb
Definition: In jewelry, tarnish refers to the dulling, discoloring, or loss of sheen on metals caused by a chemical reaction between the metal and sulfur-containing substances in the air, leading to the formation of a surface layer of corrosion. This process is particularly common in silver jewelry but can also affect gold, copper, and other metals. Regular cleaning and proper storage can help prevent tarnish, maintaining the metal's original appearance and luster. Tarnishing is generally reversible; polishing the affected jewelry can often restore its original shine. For more delicate pieces, a professional cleaning is recommended to avoid damage.