Why silver tarnishes
As the purity of the silver increases, the problem of corrosion or tarnishing also increases.
Chemically, silver is not very active — it does not react with oxygen or water at ordinary temperatures, so does not easily form a silver oxide. However, the other metal in the alloy, usually copper, may react with oxygen in the air.
The black silver sulfide (Ag2S) is among the most insoluble salts in aqueous solution, a property that is exploited for separating silver ions from other positive ions.
Sodium Chloride (NaCl) or common table salt is known to corrode silver-copper alloy, typically seen in silver salt shakers where corrosion appears around the holes in the top.
Removing silver ring tarnish
A number of products have been developed for the purpose of polishing silver, most serve to remove sulphur from the metal without damaging or warping the metal. As harsh polishing and buffing can permanently damage and devalue an antique piece of silver, valuable silver is typically hand-polished to preserve the unique patina of an older piece. Techniques such as wheel polishing, which are typically performed by professional jeweler or silver repair company, are reserved for extreme tarnish or corrosion.
The easiest way to clean jewelry without scrubbing, polishes, or harsh
chemicals, this unit uses water and gentle ultrasonic waves to dislodge
dirt and dust from rings, glasses, bracelets, and necklaces. Simply place
jewelry in the 20-oz. chamber, fill with water, close the see-through
cover, and turn it on. A powerful but gentle 42,000-cycle energy wave
quietly scrubs your valuables ultrasonically. In three minutes, jewelry is
ready to wear. Buy it for discount at Hammacher