We all know that gold is yellow. But were you aware that gold can come in a variety of colors? And they can all be called “gold”?
There a common denominator, however. All the different kinds of gold have a certain amount of the actual metal (gold) in them – just varying amounts of it. Gold is mixed with other metals to achieve different effects. These mixtures are called gold alloys.
Some of the more common names for these gold alloys are
- Yellow gold
- White gold
- Rose gold
- Green gold
- Gray gold
- Purple gold
- Blue gold
All of these varieties are made differently to arrive at the desired color.
The reason gold is mixed with other metals is that pure 24k gold is so soft that it is not suitable for making jewelry. That’s why you see 22k on down to 10k when shopping for a gold product. The metal must be mixed with another metal in order to keep its shape. Thus we have an alloy with other metals in every type of gold product. Each of the types of gold above is created by mixing different percentages of some common metals with pure 24K gold.
Yellow gold is an alloy of gold, silver, copper and zinc. It has a gold color because usually over 90% of its composition is 24K gold. Most often, it is 22K, although the weight can vary somewhat. The lower the karat rating, the less golden, but the piece is harder and is less subject to wear.
Most of the gold jewelry you see is yellow gold, and it is by far the most popular version of the metal.
After yellow gold, white gold is the most widely used. Commonly alloyed with palladium or nickel, and sometimes platinum, white gold must then be plated with rhodium, a form of platinum. This makes the metal have a white tint.
Copper alloyed with gold causes a rosy hue. If less copper is used, the result is termed “pink gold”, and if more copper is used, we get “red gold”. Rose gold is the most commonly used of the three, and is often made into wedding rings and bracelets.
Black gold can be created in several ways. It can be plated with black rhodium or rhuthenium, or its surface can be changed through chemical or heat treatment. Several different metals and chemicals may be used.
There are a number of variations of color with green gold, depending on the percentage of different metals used in the alloy. Silver makes the traditional green gold, with cadmium and copper sometimes added for slightly different hues.
Add manganese to the alloy with silver and gold and you will produce a grayish colored metal.
You hardly ever see purple gold because it’s made of an alloy of gold and aluminum which makes the resulting metal very brittle.
Blue gold is also not commonly produced due to its brittle nature. But some processes may be used to harden it. One of the most common methods is to use about 25% iron and heat the resulting alloy, which becomes blue on its surface.
So there you have it. Who knew there were so many variations in choosing gold jewelry? Now when you go shopping at the jewelry store, you will have more questions to ask.