White gold doesn't exist in nature. It is a mixture of yellow gold and nickel, palladium, rhodium, and other metals, which turns the yellow gold to white. Very common in jewelry, 18 karat white gold is often used in watchcases and bracelets, especially as a less expensive, similar-looking alternative to naturally white platinum.

By weight white gold is usually 75% gold, 3% silver, 12.5% palladium and 9.5% copper (although combinations of gold, silver, nickel, zinc and copper are used quite often). Although very expensive, the addition of palladium (or even less costly nickel and zinc) makes this form of gold very hard compared to most others.

Since white gold has such a low percentage of copper content, it is the least likely gold alloy to cause an allergic reaction. Moreover, 18 karat white gold polishes well, resists scratching and is one of the two densest colors of gold.