White gold has become very popular and serves as a less expensive alternative to platinum. Like yellow gold, white gold can vary in purity. White gold always contains other metals which slightly improve its durability and lighten its color. Remember, gold is a very soft metal, hence you rarely see jewelry that’s pure gold (24 karat). Most white gold is made with an alloy combination of gold-palladium-silver or gold-nickel-copper-zinc.
Because nearly one in eight people have sensitivity or an allergy to nickel, many jewelry manufacturers avoid using nickel in white gold. But the presence of nickel is quite common in antique white gold pieces, namely rings and brooches.
In the past, virtually all white gold jewelry was a true alloy. Today white gold is usually plated with rhodium to make it extra shiny. This plating eventually wears off and requires touching up. As the plating wears off, you may notice your white gold turning dull gray or brown.
As with yellow gold, white gold must contain at least 10 karats of gold to be legally sold as gold jewelry in the United States. 14k and 10k white gold is most common, although 18k white gold is also available and typically used in higher quality jewelry. 14k white gold is the most popular because it’s stronger, more scratch-resistant and less expensive than 18k gold. You can look inside your jewelry to find a karat stamp or hallmark that indicates the gold purity.
As far as worth, yellow gold and white gold of the same karat have the exact same percentage of gold so they’re worth the same amount, per gram. These are all important factors to consider when you buy or sell jewelry. To learn more about valuing your jewelry, check out this article: How Much is Your Gold Worth?