Silver is a pure metallic element, and white gold is an alloy created by combining gold and a white metal. Common metals used in the creation of white gold include nickel and palladium.
Pure silver is an excellent conductor, soft, malleable and ductile. It is colored almost white and has a lustrous appearance.
The properties of white gold vary depending on what other metals were used to make the alloy. Because of this, white gold made using different metals is often used for different purposes. White gold alloys made of nickel are strong and hard, so they are commonly used to make rings or pins. Palladium alloys, on the other hand, are soft and pliable. This makes them good for creating white gold gemstone settings.
The highest quality of white gold is generally 18 karats and made with palladium. Other metals, such as silver or platinum, can be added to improve the alloy's durability or change its weight. A thin layer of rhodium is also commonly applied to white gold to give it a dull luster similar to platinum or sliver. That layer of rhodium, however, can wear off over time.
Around 1/8 of the population is allergic to nickel and can develop minor rashes from wearing white gold alloys containing nickel.