Tarnishing is caused by a chemical reaction between silver and airborne sulfur compounds. When joined together they form a thin black layer of silver sulfide.
There are a number of silver polishes on the market, or you can make your own by mixing baking soda with water to form a paste. The polish should be applied and removed lightly, not scrubbed. Work in an up and down pattern, not in circles.
The chemical reaction can be reversed by soaking it in a tub of hot water mixed with baking soda lined with a piece of aluminum foil.
The water needs to be near-boiling, and enough baking soda needs to be added that the water starts to fizz. When the silver comes in contact with the aluminum, it creates a chemical reaction that breaks the sulfur off of silver sulfide molecules, turning the surface back into silver. Keep in mind that this will clean the entire piece: if you want to leave some tarnish in the crevices so engravings stand out, don't use this method.
Posted 3490 day ago