What is the difference between 9 carat and 18 carat gold?

18 carat gold jewellery is made up of 750 parts pure gold out of 1000 parts, the remaining 250 parts being made up of other metals, mainly copper and silver. 9 carat gold jewellery is made up of 375 parts pure gold out of 1000 parts, the remaining 625 parts is made up of other metals such as silver, nickel, palladium and zinc. So 9 carat gold is just over 1/3rd gold content, whereas, 18 carat gold has ¾ pure gold content. So for example, say you have in front of you a mobile phone, if your phone was made of 9ct Gold, one third of the phone would be pure 24ct gold, the remaining two thirds would be made up of alloys (silver, nickel, palladium & zinc) If your mobile phone was made of 18ct Gold, two thirds of the phone would be pure 24ct gold with only one third being made of alloys - hence the difference in price between the two items.

18 carat gold is practically completely resistant to chemical attack in normal use, whereas 9 carat gold is much less resistant. Be aware that 9 carat gold will tarnish, go dull, bleach some fabrics and sometimes turn black from chemicals in the atmosphere, perspiration and household cleaners. That is why sometimes some people have an allergic reaction to wearing 9 carat gold, leaving black or green marks on the skin. This is a chemical reaction to the metal alloys, not the gold, usually the nickel in 9 carat gold reacting with the skin. Nickel is the most common cause of dermatitis through allergic reactions when in contact with the skin.

Nickel is not present in 18 carat gold. Our 750jewellery 18 carat gold items are nickel safe and our policy is to use only ’white gold’ alloys containing palladium.

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