Sterling silver consists of 92.5% silver, and the remaining part is copper. This is the reason why sterling silver is popularly referred to as "925 Sterling Silver" or just 925 Silver. Silver needs to be combined with other metals because it is very difficult to make great designs with just pure silver, which is soft and malleable.
A bit of hardness has to be introduced, by adding other metals such as copper or brass. That’s why jewelers are capable of making intricate and complex designs with 925 sterling silver.
Pure silver is not susceptible to tarnish in a pure oxygen environment. However, the copper that is contained in 925 sterling silver may react to the ozone and hydrogen sulfide in the air and cause sterling silver to tarnish. Perfumes, hair sprays, and profuse sweating can also cause a quicker formation of tarnish.
You won't be able to 100% prevent tarnish from forming, but there are a few ways you can significantly delay the formation of tarnish.
The best way is to wear your sterling silver jewelry frequently. The oils in your skin will "clean" the sterling silver every time you wear a piece.
Another way to delay tarnishing is to store sterling silver in an airtight container, preferably with an anti-tarnish strip (a specially formulated material that absorbs moisture). Anti-tarnish strips are available on Amazon or your local Walmart store.
While it may not look pretty, plastic zip-top bags are the best container to use to store your jewelry. A jewelry box with a tight-fitting lid is also a good option.
A great way to clean tarnish off silver is with dish soap. Form a lather with your hands and rub the tarnish off your silver.
Silver plated items are made from a thin coating of pure silver over other metals. When the coating of silver flakes or scrapes off, the base metal underneath is revealed.
All silver-plated jewelry will tarnish at some point, as the chemicals from daily wear and the exposed layer of silver react with air to change the color of a piece. Silver-plated jewelry has a thin layer of silver that covers a base metal, often brass. Because the coating is thin on the base, cleaning needs to be careful but complete to keep up an item's shine.
The Best way to Clean Silver-Plated Jewelry:
Cover the inside of a bowl with aluminum foil.
Pour 1 tbsp. baking soda and 1 tbsp. salt into a bowl.
Fill the bowl half full of hot water.
Stir the contents of the bowl to mix them.
Submerge the silver plated jewelry in the solution.
Wait 10 minutes before removing the jewelry.
Rinse the jewelry and wipe it dry with a lint-free cloth.