White gold is an alloy of

White gold is a precious metal alloy created by mixing pure gold with white-toned metals to mask its natural yellow hue. The most common formulations for white gold involve alloying gold with nickel, palladium, or silver. Specifically, nickel-based white gold is known for its hardness and strength, making it suitable for rings and pins, while gold-palladium alloys are softer and more pliable, often used for gemstone settings [1]. A typical high-quality white gold formulation might consist of 90% gold and 10% nickel, or a combination of gold, palladium, and silver [1]. While other metals like copper, zinc, or manganese may be added in smaller quantities to improve malleability or durability, the primary bleaching agents that define the alloy as 'white gold' are nickel and palladium [1]. Therefore, the combination of gold, nickel, and palladium correctly identifies the primary constituents of white gold alloys.

Sources

1. [1] https://en.wikipedia.org/wiki/White_gold