A eco friendly way to clean Silver Plated is with baking soda and aluminum foil.
1: Line the bottom of a small bowl with a piece of aluminum foil.
2: Add salt and baking soda to the bowl, then add enough hot water so that your jewellery piece will be covered. Mix the solution so the powders dissolve.
3: Add the jewellery to the bottom of the bowl. Black and yellow flakes will begin to break off or float up in the water as the sulfur (what darkens the jewelry) separates from the silver and is attracted to the aluminum in the bowl.
4: Remove the piece after 10 minutes, or when you see that the tarnish or dirt seems to have mostly disappeared.
5: Rinse the piece under lukewarm water, then dry with a soft, lint-free cloth.
The best way to clean your Sterling Silver and to prevent or remove dirt and tarnish, is to use a silver polishing cloth or any anti-tarnish silver polish. Rub the cloth on the piece until it is shiny again.