Over time silver jewellery may naturally tarnish due to oxidization from the air, this can give an aged or vintage look to your jewellery which can look great, but if you prefer to keep your jewellery all sparkly and shiny, it is easy to refresh by simply using a jewellery polishing cloth or even in warm soapy water and a soft bristle brush (make sure it is soft to avoid scratching the metal).

One thing to note is that if you buy jewellery with black patina already on it, this is purposely oxidized silver to give a contrasting effect, using a polishing cloth over these areas may remove the black patina and reduce the effect, try to avoid polishing these areas.