Genuine silver-- aka sterling silver-- is a beautiful and valuable metal that, with proper care, can last for many years. Because it is a soft metal, silver alone cannot be used to construct jewelry, flatware or other durable items. To compensate for its malleability, silver is often mixed with other metals. For an item to qualify as genuine silver, it must be 92.5 % pure. Most sterling silver is composed of 7.5 % other metal, typically copper. Jewelry or other substances composed primarily of other metals and coated with only a thin layer of silver are called silverplated. Because the layer of silver is so thin, it's susceptible to degrade over time, with wear and tear. Like gold, genuine silver must have a trademark noting its purity Genuine silver is denoted with a "925 silver" etching, while silverplated items are not.
Genuine Silver vs. Silverplated: How to tell?
Carefully inspect your item for a sterling silver notation. If you are looking at jewelry, check the clasp. You should see one of the following markings or something similar: "9.25," "925/1000," "Sterling," "S/S" or "Sterling 9.25." If you do not see any of these markings, it's highly unlikely the item is genuine silver.
If you do not see the sterling marking, the item is probably silver-plated. Check the coloring of the item carefully. Genuine silver is generally less shiny and colder in tone than silverplate. If you see places where the silver appears to be flaking off or turning green, the item is silverplated.
To investigate further, you can try cleaning the item with a soft cloth. Real silver will oxidize with friction and as a result usually leave black marks on the cloth. Exposure to air or other chemicals results in tarnishing that does not occur with fake silver. Go here, for tips on how to clean your sterling silver.
If you suspect the item is made of stainless steel (as many types of flatware are), you can try holding a magnet near the item. The magnet will be attracted to the steel but not silver.
If the item does have the sterling marking, yet you still suspect it may be fake, you can take the item to jeweler for a professional "acid test." A small drop of nitric acid (a harsh industrial chemical) will turn a non-sterling item green due to high copper content.Items that are silver-plated brass, nickel silver or low-quality silver will turn green. Be aware that nitric acid will leave a permanent discoloration on your item, so make sure it is applied in an inconspicuous spot.