What is Rhodium Plating?
Rhodium is a rare metal and is used to plate sterling silver or gold to enhance durability and appearance.
It is not necessary to plate sterling silver but plating with rhodium will stop the ring from tarnishing and will add durability it would also help if you are allergic to sterling silver as rhodium is hypoallergenic.
White gold is almost always rhodium plated. Since gold is yellow by nature other alloys are added to make the gold white. It is then rhodium plated for shine and luster.
Rhodium plating will need to be redone occasionally depending on the piece and the wearer. Rings may need to be replated after two or three years, while pendants or earrings would need to be replated in eight to ten years.