Is the only difference between white gold and yellow gold the colour? The answer is no, that is the main difference, but it's not the only one, they are made up of different properties. To make the yellow gold colour less noticeable, white properties are added to help mass the yellow colour. There is where karats of gold come into play.
The 'Karat' is a unit of measure we use to determine how much gold, compared to the other materials, is used in a piece of jewellery. For example, 14 karat gold is made up of 58.5% gold while the other 41.5% is made up of alloys. The most common alloys used in gold are; copper, zinc, silver, palladium, and nickel. In white gold, the alloys used are typically the white property alloys such as; silver, palladium, and nickel. These alloys are what make “white gold” white. The percentage of gold also determines how yellow the jewellery turns out in white gold as the Karats adjust the amount of gold used when creating new pieces of jewellery.
The colour of gold should be chosen on your personal preference however, white gold is slightly stronger and more durable than yellow gold. White gold requires a bit more maintenance than yellow gold as over time the rhodium plating by your jeweller as it can wear off and your jewellery will start to "yellow". Yellow gold is more hypoallergenic than white gold and it’s easier to maintain but still requires a clean and polish every few years.