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What are the different gold carats?

Gold carats

When we talk about what ‘carat’ gold is, we mean how much of the metal alloy is pure gold.  An alloy is a mixture of different metals. The word ‘carat’ is used differently from how the word is used with diamonds, where carat is used to describe the weight of the stone.  When it comes to jewellery, gold is usually weighed in grams.

There are many different alloys used around the world. Therefore you will be more familiar with the various carats (ct) of gold depending on where you live.

In the UK, 9 & 18ct are by far the most common.  In the US, 9,10 & 14K golds are widely used and high carat golds like 22 or even 24ct are used in India where gold is used as a store of wealth.

Gold, in its natural state, is very soft.  This makes it fantastic to work with and it can be easily formed but less suitable for use in jewellery so it has been mixed with harder metals to make it stronger.

It has also been mixed with metals to change its colour.  For instance, rose gold is a mixture of gold and copper which gives it a rose colour and white gold has been mixed with silver in the past to create white gold.  

24ct gold

The highest carat gold you can get is 24ct and this is pure gold.  For every 1000 parts of metal, 1000 are gold. This gold can be used to make jewellery but great care must be taken when wearing these pieces as gold is quite soft. 24ct gold jewellery pieces are often only worn for ceremonial occasions such as weddings.

24ct gold is very popular in India where gold is used as a store of wealth by many people.

22t gold

22ct gold is the next highest carat gold that is often used.  This is 916. Again, this carat of gold is very soft and jewellery made out of 22ct gold should be worn with care. Again, India is the main market for 22ct gold jewellery.

Metals such as copper & zinc often make of the non gold parts of these alloys.

18ct gold

18ct gold is 75% pure gold.  750 parts out of 1000 are pure gold and you will see 750 stamps on a UK hallmark on an 18ct gold piece.  Although 18ct gold is a high purity alloy, modern alloys are hard enough for this metal to be worn every day without concern. 

This is the most popular alloy for high end fine jewellery as it combines wearabiliy with a rich gold colour. The presence of other metals is enough to allow for different colours of gold, such as white or rose gold to be made.

A piece of jewellery made from 18ct gold will more expensive than a 9 or 14ct piece as it contains more pure gold.

14ct gold

14ct gold is popular in the US and is 595 parts gold to other metals. As it is not widely used in the UK, you will often see a ‘14k’ stamp inside these items of jewellery as opposed to a full hallmark. Britain is the only country in the world that requires items described as gold to be individually tested so items of jewellery

Learn more about hallmarking

9ct gold

9ct gold is used extensively in the UK and the US and is 37.5% pure gold. If you see the number 375 on a stamp on an item of jewellery it means that item is mad from 9ct gold. 9ct gold is typically used for mass market and mass produced jewellery and it has a darker colour as the percentage of non gold metals is higher.

Again, metals such as silver, copper and zinc are used to created 9ct gold alloys.


Does the carat of gold matter?

Most jewellers will recommend going for a higher carat of gold if possible because it has a richer, more attractive colour. In the past, people have had concerns that because gold is a soft metal a higher carat gold piece of jewellery will be too soft however this is not the case. Modern alloying and metallurgy techniques mean that 18ct gold is as hard and durable as 9ct gold.