When coming to sell your gold, it’s important to understand how gold purity (carat) works. It is both a beautiful and rare metal and at the same time is a versatile metal that is used in everything from jewellery to technological components. Gold’s purity is described in carats (out of 24) and also by millesimal fineness (parts per thousand), e.g. 9ct = 375, 18ct = 750.
Below we explain what “carat” means, how common caratages differ, and simple ways to identify markings on jewellery, coins and bars.
“Carat” (UK spelling) comes from the historic use of carob seeds as counterweights; over time it became a unit for gemstone mass and, for gold, a fractional purity out of 24 parts (the US spelling “karat” is often used for gold).
Gold purity is shown either in carats (e.g., 18ct = 18 parts gold, 6 parts other metals) or as millesimal fineness (e.g., 750 = 75.0% pure gold). In the UK, recognised gold fineness marks include 375 (9ct), 585 (14ct), 750 (18ct), 916 (22ct), and 999 (24ct).
24ct is treated as “pure” for trade purposes (typically stamped 999 or 999.9). Although considered “pure”, 24ct is not “100%”, because small tolerances/trace impurities are normal and not because gold oxidises in air (gold is a noble metal and resists oxidation).
9ct (375) – Around 37.5% gold with alloy metals for strength. Common in UK jewellery, 9 carat gold can be favoured in making jewellery such as rings, and bracelets.
14ct (585) – About 58.5% gold. A practical balance of durability and gold content, widely used for fine jewellery. 14ct is an ideal balance of durability and being cost-effective.
18 ct (750) – 75% gold. Richer colour than lower carats while still suitable for regular wear with appropriate care.
22 ct (916) – 91.6% gold with a small amount of alloy for strength. Luxurious colour but softer than lower carats; avoid heavy daily wear.
24ct (999/999.9) – High-purity gold most often seen in bullion coins and bars; jewellery exists, commonly in the Asian market, but is soft and prone to scratching.
Choose based on how the item will be worn: many people prefer 9–18ct for everyday durability, while higher carats offer a richer colour but are softer. Higher purity jewellery can be chosen for more occasional wear. If you’re comparing metals for investment purposes, seek guidance from an FCA-authorised adviser.
Typically, the gold carat should be stamped on the inside of the piece of jewellery or stamped somewhere on the gold bar or coin. This purity stamp will usually appear as ‘9CT’, ‘9’ or ‘375’ for 9 carat and may require you to use a magnifying glass or loupe to see the stamp clearly.
If the gold piece doesn’t have anything to distinguish the purity of the gold, then you can bring your gold into our Warrington store or send your gold to us via the post and we can perform purity tests on your gold to identify its purity.
We’re here to help you get a transparent and fair valuation for your gold and when you send us your items we can let you know exactly what the item is worth, the gold purity and our offer. You don’t have any obligation to us at Cheshire Gold Xchange, but we would be glad to help you.
Receive your prepaid, insured envelope to send your gold to us. Find out more visit Sell Gold Online
