White gold rings is described by karat weight just like yellow gold. It can be 18kt, 14kt, 9kt. Eighteen-karat yellow gold is 75% gold mixed with 25% other metals. White gold is 75% gold with 25% other white metals like silver. So the same amount of gold and alloy is used but the type of alloy depends on whether white or yellow gold is the desired result.
When purchasing white gold rings, try to find out what alloy the ring uses. Many people are allergic to nickel. Usually such rings are made with a different white metal because of this. Sometimes antique gold rings jewelry will have nickel in them. If possible, it would be best to try to find out.
Be sure to shop around when purchasing any jewelry. Fine jewelry is an investment and should not be purchased casually. There are many local stores. There are online merchants and auctions. Even pawnshops will often sell these rings at top notch quality. Get a receipt and get a warranty. Then get the ring appraised and know for sure what is being purchased.
This type of white gold rings looks stunning and is expensive. Set with diamonds, the whole ring sparkles. The rings come with other gems too but the diamond is the gem of choice for many buyers.
The rings also look very similar to platinum rings. They have been referred to as the rich man's silver or the poor man's platinum. Regardless, white gold is an alternative for people who like white jewelry but do not want silver or platinum.