Yes, silver can tarnish over time. This natural process is called oxidation. During oxidation, silver reacts with substances in the air, such as sulfur compounds, or with skin oils upon contact. As a result, the surface of the silver may develop a black, milky, purple or sometimes green haze. Tarnishing does not affect the intrinsic value of the silver.
Silver coins can tarnish when stored in a humid environment or touched by hand. This can cause milky spots to appear, or the coin may gradually become darker or blacker. As long as the coin is not physically damaged—for example, by dents or scratches—tarnishing does not affect the buyback price.
If you store your coins yourself, we recommend keeping them in a dry, dark, and secure place, preferably in protective capsules or sleeves to minimize contact with air and skin oils.
For silver bars, tarnishing is hardly an issue. Even if a bar darkens slightly over time, this does not affect the buyback price when you sell it. Its value is determined solely by its weight and silver content.
For collectible silver coins, tarnishing can affect the collector’s value. Collectors often care about the appearance and condition of a coin. A heavily oxidized coin may therefore fetch slightly less than one in perfect condition.
By comparison, gold, platinum, and palladium do not oxidize and retain their shine even after prolonged exposure to air or handling.
Read more about the difference between silver bars and silver coins
Also read more about selling silver, selling silver bars, and selling silver coins.
Learn more about the difference between new silver coins and mixed-year silver coins.