Guides · 29 October 2026 · 2 min read
Karat, purity and what 24K, 22K and 18K really mean
What the carat number on gold jewellery means, how 24K, 22K and 18K differ, and how to choose the right purity for the way you will wear a piece.
In short
- Karat tells you how many of 24 parts are pure gold.
- 22K suits traditional pieces. 18K suits stone-set and everyday pieces.
- Higher is not always better, because pure gold is soft.
You will see numbers such as 24K, 22K and 18K on almost every piece of gold jewellery. They describe purity, and they are easier to understand than they look.
The idea behind karat
Pure gold is divided into 24 parts. The karat number tells you how many of those 24 parts are gold. The rest is a mix of other metals, commonly copper and zinc, added to make the piece stronger and to shape its colour.
| Karat | Parts gold | Fineness stamp |
|---|---|---|
| 24K | 24 of 24 | 999 |
| 22K | 22 of 24 | 916 |
| 18K | 18 of 24 | 750 |
| 14K | 14 of 24 | 585 |
The fineness stamp is the same idea written per thousand. A 22K piece is 91.6% gold, which is why you see 916 beside it.
Why purer is not always better
Pure gold is soft. A 24K piece will dent and bend with daily wear, so it is generally kept for coins and bars, not for jewellery that is worn often.
Adding other metals makes gold harder. That is why most traditional Indian jewellery is made in 22K: it keeps the deep, warm colour people love and is still workable enough for detailed craft. Stone-set pieces, and pieces meant for everyday wear, are often made in 18K because the extra strength holds stones more securely and resists scratches better.
Choosing for the way you will wear it
- For ceremonies and heirlooms: 22K is the traditional choice, valued for its colour.
- For everyday wear: 18K is more durable and holds up to daily life.
- For delicate stone settings: ask which purity the jeweller recommends and why.
Colour comes from the mix
The shade of gold, whether yellow, rose or white, depends on which metals are mixed in. This is a design choice, not a sign of quality. Two pieces of the same karat can look quite different.
What to ask
Ask for the purity of each piece, and check that it matches the hallmark stamped on it. Our guide to reading a hallmark shows where to look.
If you are unsure which purity suits a design, message us and we will explain the options for that piece.
