Remember when you were a kid and there was only one type of gold? When you thought of gold, you thought of yellow gold. If you had seen white gold, you probably would have assumed it was silver, and very few people knew anything about rose gold, or any other kind of gold for that matter before Apple started selling all of their products in a variety of colored metals. This begs the question, what gives gold its color? And what’s the difference between all of these different types of gold, anyway? Well the answers are pretty simple, and it all comes down to the metal alloy, but let’s first cover all the major bases when it comes to gold in general.
Gold is measured in karats, and there are 24 of them
By now you probably know that gold is measured in karats, and the more of them you have, the more pure the gold is. Pure gold is 24 karats, and in its pure form it’s a very malleable metal. That’s why it’s usually alloyed with other metals, to make it much harder. In certain countries, like India and China, it is a lot more common to find jewelry made from 22 karat yellow gold, and the color is very yellow, but the metal is still so soft, that it often loses shape very easily. In the Western hemisphere, most jewelry is made from either 14 or 18 karat gold.
What makes up the rest of the alloy?
When you alloy the gold with other metals, there are changes in both the color and the hardness. If you want to keep the gold yellow, then it is usually blended with a mix of nickel and copper. The nickel is white in color, and the copper has a reddish-brown hue, but since the gold dominates the alloy, it remains rather yellow. When you want to make white gold, the copper is omitted and the gold is blended solely with nickel, which has an effect that nearly bleaches out all signs of yellow. Likewise, when you want to make rose gold, the nickel is omitted, and the copper gives the gold a pink hue.
White gold requires upkeep
The last thing you need to know is that white gold has a tendency to start looking a little bit yellow over time. That’s why most white gold jewelry pieces are given a rhodium plating, and those pieces need to be re-plated with rhodium about every 10 years. Rhodium is a metal that belongs to the platinum family, and it keeps white gold looking super white and shiny.
In the end, gold comes in just about every color of the rainbow, it just has to be alloyed with different metals in order to achieve any given color. However, yellow, white and gold are definitely the most popular by far.