Creation of Colors

• An 18-karat white gold ring contains the same amount of gold as an 18-karat yellow gold ring: 75 percent pure gold. The difference in the color comes from the different metal alloys with which the gold is mixed before its use. Yellow gold is made by mixing pure gold with the alloy metals copper and zinc. White gold is made with an alloy of gold and some white metals such as silver and palladium. Nickel was traditionally used in the making of white gold, but since many people have allergic reactions to the metal, it is no longer used today.
  
  

White Gold Pros

• White gold is widely chosen for wedding rings. Lots of people prefer its silver color to that of yellow gold but don't want to spend the hefty price tag for platinum or titanium. White gold is also more durable and scratch resistant than yellow gold, thanks to the stronger alloys with which it is paired. However, white gold is still lightweight and soft enough for jewelers to work with. White gold rings are easy to re-size if necessary, but titanium rings usually cannot be, and platinum rings can be difficult. White gold in wedding rings has the further advantage of highlighting the diamond---yellow gold could create the illusion of a yellow tint on some stones.
  
  

White Gold Cons

• Older white gold rings were most likely made using nickel. If you are allergic to nickel, you might want to avoid family heirloom or vintage white gold rings. Ask the jeweler what kinds of alloys were used in mixing his white gold. Another problem you could encounter with white gold is an apparent fade in color---most white gold rings are coated in rhodium to make them appear brighter and more silver (the actual color of most white gold is a light gray). However, rhodium does wear off eventually, so you'll need to get your ring re-rhodium plated about once a year. The jeweler you purchased the ring from should do this for a reasonable, discounted price.
  
  

Yellow Gold Pros

• Yellow gold is the classic color for rings (and most jewelry). If you like antique rings, you can find quite a few choices in yellow gold, especially rings dating from the late1930s and 1940s, when yellow gold rings were in vogue. Yellow gold was also popular during the Edwardian period of 1901 to 1910. Yellow gold also does not need to be re-plated the way that white gold occasionally does, and the chance of allergic reactions to the alloys used in yellow gold is much lower (about 20 percent of the population is allergic to nickel in white gold, whereas zinc or copper allergies are rare).
  
  

Yellow Gold Cons

• Yellow gold looks great with warm skin tones, but it might make people with cool skin tones (those skin tones without any yellow in them, with more rosy or pale skin instead) look sallow or washed-out. Yellow gold is not overly in demand at the moment---the current trend is toward white gold and platinum materials in rings, so if you're buying for someone who prefers to be on the cusp of the trends, this may be an issue. Also, yellow gold needs to be polished frequently to retain its shine, and it is softer than white gold, and thus more vulnerable to scratches and marks.