Apart from the most common yellow colour of gold, you can find other variants. The different gold colours are produced depending on the types of combining metals in different proportions. These colour variants include the following:
1. Pure Gold
The purest form of gold is slightly reddish yellow in colour. It is of 24 karats and contains no other metals. However, jewellers do not use this form to make jewellery as it is very soft and malleable and not suited for everyday use. Therefore, instead, they alloy it with other metals to make more durable jewellery.
2. Yellow Gold Alloys
Yellow gold alloys can be produced by combining pure gold with silver, copper, or zinc. This looks similar to the pure form but adds durability and strength to its structure. However, the purity of this type is about 75%, with 12.5% of copper and silver each. It is the most popularly used form of gold jewellery in India. Yellow alloys mostly come in the purity range of 18k to 22k, which makes for durable jewellery.
3. White Gold
The white gold colour is gained through the combination of pure gold with silver, nickel or palladium. Another popular way to achieve this colour is by mixing gold and platinum. The gold purity of this variant is generally 18 karat which is produced by mixing 90% gold with 10% of nickel or silver. Therefore, it is scratch-resistant and durable and is often coated with a layer of rhodium to give it an added shine. It is often preferred over platinum to make diamond jewellery.
4. Rose Gold
Rose gold is an alloy made of predominantly copper, silver and gold. It constitutes 75% of gold, 22.25% copper, and 2.75% silver. Moreover, there are two other variants of this kind: red gold and pink gold. All of these variants are made up of the same metals. However, the difference in colours depends on the percentage of copper in the alloy. Generally, rose gold jewelleries are of 18k gold. However, 22k rose gold, also known as crown gold, is its highest karat version.
5. Green Gold
Green gold is a rare variant of a gold alloy, also known as Electrum. Unlike the other kinds, green gold forms naturally comprising silver, gold and sometimes copper. The greenish-yellow colour forms due to the presence of silver. Artificially, it can be produced by mixing cadmium with gold. The amount of the different metals used are 75% gold, 15% silver, 6% copper, and also, 4% cadmium.
6. Grey Gold
This is also one of the rare gold forms. It is produced by blending gold with palladium. However, many goldsmiths use magnesium, copper or silver instead of palladium to manufacture it in a much cheaper way. Grey gold is mainly made out of 18k gold and is often formed naturally due to high iron proportion.