Many people now prefer the look of silver jewellery rather than gold so white gold is often a very popular choice. To change the colour of gold, yellow gold is mixed with one or more metals, resulting in an alloy that is white. Most white gold jewellery offered today has been plated with rhodium. Over time this coating can be come discoloured and removed leaving the jewellery looking tarnished or back to a more original gold colour. This process is sped up by wearing your jewellery often especially if it is getting wet, exposed to chemicals or worn on a finger for example that often gets more damaged than a necklace earrings.
The best way to preserve the colour of your white gold jewellery, apart from not wearing it, is to have it re-plated.
If your white gold jewellery has a lot of scratches, you may want to get rid of them by having it polished, however it is important to understand that when polishing white gold jewellery you are removing all or part of its rhodium plating, and it won’t be long before you will have to pay again to have it recoated.