White gold like all other colors of gold is an alloy containing metals to achieve a specific color. The white color is achieved by alloying pure yellow gold with “bleaching” metals. Nickel, palladium, platinum, iron and chromium are strong whiteners of gold. Zinc and silver are less powerful. White gold is sometimes plated with rhodium to whiten and strengthen the piece. In fact, many consumers unwittingly consider the rhodium plated white gold to be the actual color of “white gold”.
White gold alloys were first developed in the 1920s as an alternative to the more expensive white metal, platinum. White gold is an excellent choice to set off diamonds in wedding and other jewelry when platinum is too expensive.
Different alloys produce different degrees of whiteness with the preferred color as close to platinum as possible. There is no industry standard formula for white gold, thus what is considered “white” covers a range of colors including the preferred silvery white of platinum, pale yellow and even pale pink. The use of rhodium plating which consumers may not be aware of, covers a wide range of “sins” in white gold color.
Most white golds today fall under one of two categories: nickel white or palladium white. The nickel whites are alloys containing gold, nickel, silver and zinc with some copper added to improve workability during manufacturing. But, with the addition of copper comes some degradation in whiteness, therefore most nickel white gold today is plated with rhodium which further enhances the whiteness, shine and hardness of the finish. The palladium white golds are alloys of gold, palladium, silver and zinc. More expensive to manufacture, nickel white gold plated with rhodium is more common today.
White gold is most commonly used in 10 karat, 14 karat and 18 karat gold jewelry – either alone – or in combination with yellow and other colors of gold. Karat gold up to 21K can be made in white but beyond 21K, the white color is not achievable.
The percentage of gold contained in an item of white gold for example is exactly the same percentage of gold contained in yellow gold. In the case of 14K gold for example, there is 58.3% gold in white gold or yellow gold. Only the metals alloyed with the gold change according to the color. GoldFellow® computes scrap gold prices it pays consumers based on gold content and weight, therefore 14K white or yellow gold are valued the same.