Sterling silver is odorless, so go ahead and smell the piece in question. If you can smell sulfur or a distinct metallic fragrance, then it is not sterling silver. The item could be silver-plated, but a scent indicates that it is not made entirely of sterling silver.

The Polish Test

Silver needs to be polished on a regular basis. Rub the tarnished piece as if polishing. If no black residue appears on your cloth, it's not silver." Polishing the silver item is a very good indicator of its authenticity. Rust or a lack of oxidation indicates that the item is made of a different material from silver.

The Flake Test

Some items may be silver-plated, which means that they are covered with a layer of real silver. 

The Ring Test

Silver has a nice ringing sound when it is tapped. If it is a coin, you can flick it into the air. Alternatively, you can gently tap it with another coin. In both instances, you should hear a high-pitched bell-type ring that lasts about 1-2 seconds. 

Ice Cube Test

Another easy method to check whether the silver is pure or not is by using ice cubes. This method is ideal for testing silver coins and other silver items with flat surfaces. Place an ice cube on a silver coin or flatware. If the ice cube melts quickly, then the metal you own is real. Silver has the highest thermal conductivity and when you place an ice cube on silver, it will melt at a faster rate. Although it melts at room temperature too, it will melt faster when placed on a silver coin or flatware.