Different Colours of Gold Jewellery
There are quite a few different colours of gold jewellery but, the three most popular colours are yellow, white and rose, especially when choosing wedding and engagement rings.
In its purest form gold is 24k very bright yellow and too soft for jewellery. All other colours are produced by mixing gold with other metals. Your gold jewellery will almost always be a mixture of gold and another metal.
Yellow Gold
Creating different colours involves mixing the pure 24K gold with other metals. The gold then becomes an alloy.
For example, 14K gold is an alloy consisting of fourteen parts pure gold and ten parts of other metals.
Most of the gold jewellery we wear is not pure gold.
Pure gold is 24 Karat and yellow.
Gold in any other colour is an alloy.
An alloy is a mixture of metals. Alloys of gold, silver, copper, zinc, palladium and nickel create different hues of gold.
White Gold
Alloys of gold and silver-coloured metals create white gold.
It is not a true white metal, it will always have a slight yellow hue.
The gold gets its bright white colour by plating it with rhodium.
The rhodium plate will eventually wear off leaving the piece of jewellery slightly yellow.
Re-plating the jewellery will return it to its white colour.
Rose Gold
Over the last years rose gold has become more popular.
Also known as Pink Gold it has a very subtle colour which intensifies with age.
Viewing under different circumstances such as natural light and fluorescent light may make the pink hue show up differently.
Copper and silver create the colour rose.
4% silver and 21% copper added to 75% gold typically makes 18K rose gold.
Rose Gold is available in 18K and 14K.
Other Types of Gold
Green Gold
Green gold is made of pure gold and pure silver and has a light sage green hue.
Adding zinc or nickel makes the gold more durable.
Green Gold is available in 18K and 14K.
Black Gold
Black gold isn’t created by the process of alloying, whereas the gold used is usually an alloy and not the pure 24K.
Methods used to create black gold are external coating, electroplating, heat treatment and controlled oxidation.
The combination of the hue of the original metal and the method used to colour it will determine how deep the final black of the gold becomes.
The most common technique for creating black gold is electroplating to add a layer known as a patina.
Electroplating with rhodium or ruthenium is most common, often starting from 18 karats white gold.
Although black gold jewellery isn’t everyone’s taste, it is undeniably eye-catching and unusual.
Black gold is often used by designers because the colour works well with diamonds and other gems.
Jewellery made from black gold is often more expensive than in other gold colours.
Purple Gold
Purple gold is also known as amethyst or violet gold. It is made by mixing gold and aluminium at a fixed ratio.
Due to the gold content being almost 79%, purple gold qualifies to be referred to as 18K gold.
Blue Gold
Blue gold is an intermetallic compound of gold and indium.