#1. Rub the jewelry using a soft white cloth.
If you find any black marks on the cloth, then you can be sure that it is made of real sterling silver. since any air exposure causes real sterling silver to oxidize causing the black marks.
#2. Use the Smell Test.
Real sterling silver shouldn’t smell. If it does, it is because there is too much copper in it.
#3. Use the Magnet Test.
Magnets have no effect on silver – just as they have no effect on gold or platinum. But if you find that the jewelry is attracted to the magnet, then it will be clear to you that it is not made of real sterling silver.
#4. 925 markings.
Real sterling silver jewelry will have markings such as “Ster,” “925” or “Sterling Silver” in a hidden area. If you don’t see such a marking, be wary of it immediately.