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Karat and Purity: What 24K, 22K and 18K Really Mean

Karat is not quality or brand — it is a fraction. Once you can read it, you can tell what you are actually paying for.

4 min read · Updated 2 Sep 2026

Au Purity is just a fraction Karat = parts of pure gold out of 24 parts of metal. 24K pure gold — bars, coins 99.9% 22K jewellery and most coins 91.6% 18K harder, more alloy, less gold 75.0%
Karat is a fraction: how much of the metal is actually gold.

Every piece of gold you will ever be offered is a mixture. Karat tells you how much of that mixture is gold and how much is other metal — copper, silver, zinc — added to make it harder or cheaper.

The scale runs to 24. So 24 karat means 24 parts out of 24 are gold: as pure as gold is sold. 22K means 22 parts gold, 2 parts something else.

The three numbers you will meet

  • 24K — 99.9% pure. Soft. This is what bars and investment coins are made of.
  • 22K — 91.6% pure. Hard enough to wear. Most jewellery and many coins.
  • 18K — 75.0% pure. Harder still, cheaper, and a quarter of it is not gold.

Read the hallmark, not the label

Shops stamp purity as a number: 999 for 24K, 916 for 22K, 750 for 18K. That number is parts per thousand. A tag that only says “pure gold” with no stamp on the metal itself tells you nothing.

Which one should you buy?

It depends on why you are buying. If you are buying gold to hold value, every non-gold gram you pay for is dead weight — 24K bars and coins are the cleaner choice. If you are buying something to wear, 24K will bend and scratch; 22K exists for exactly that reason.

The trap is paying a 24K price for 22K metal. That is why the stamp matters more than the shop’s reputation.

Same 10 grams, different gold content

PurityGold in 10 gNot goldTypical use
24K (999)9.99 g0.01 gBars, investment coins
22K (916)9.16 g0.84 gJewellery, coins
18K (750)7.50 g2.50 gStudded and export jewellery

See it on real gold

Our store lists 24K bars and 22K coins with the purity printed on every item.

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