Gold Karats and Purity: 10k, 14k, 18k, 22k and 24k Explained
Gold is too soft to wear on its own, so jewelry is usually an alloy: gold mixed with silver, copper, zinc or other metals. The karat number says how much of the piece is gold. This guide shows what each karat means, the stamps you will find on jewelry, and how to work out what your gold is worth.
What a karat means
Karat (k or kt) counts gold in parts of 24. 24 karat is pure gold; 18 karat is 18 parts gold and 6 parts other metal, which is 75% gold. Divide the karat by 24 to get the gold content.
Gold purity chart
| Karat | Gold content | Stamp (fineness) | Where you see it |
|---|---|---|---|
| 24k | 99.9% | 999 | Bullion bars and many investment coins |
| 22k | 91.7% | 916 or 917 | Gold Eagles, Krugerrands, much jewelry in India and the Middle East |
| 18k | 75.0% | 750 | Fine jewelry and watches |
| 14k | 58.3% | 583 or 585 | The most common jewelry in the United States |
| 10k | 41.7% | 417 | The lowest karat sold as gold in the United States |
| 9k | 37.5% | 375 | Common in the United Kingdom |
The stamp is the gold content in parts per thousand, so 585 means 58.5% gold. You will usually find it inside a ring, on a clasp or on the back of a pendant. Marks such as GF (gold filled), GP or GEP (gold plated) and RGP (rolled gold plate) mean only a thin layer of gold over another metal.
Silver, platinum and palladium marks
- Silver: 999 is fine silver, 925 is sterling silver (92.5%), 900 is common in older coins, 800 is found in some European silver.
- Platinum: 950 (95%) is the usual jewelry standard; 900 and 999 are also used.
- Palladium: 950 and 999 are the common marks.
How to work out what your gold is worth
- Weigh it in grams. A kitchen scale is too rough for small pieces; a jewelry scale reads to 0.01 g.
- Find the karat from the stamp and turn it into gold content with the chart above.
- Multiply: weight in grams × gold content × today's gold price per gram. That is the melt value, the value of the gold alone.
Example: a 10 gram 14k chain holds 10 × 0.583 = 5.83 grams of pure gold. Multiply 5.83 by today's price per gram on our Markets page for its melt value. A buyer pays a share of the melt value; our We buy gold estimator shows what The Gold App pays from the live price.
When the stamp is missing or worn
A stamp can be missing, worn away or simply wrong. An acid test, an electronic tester or an XRF reading confirms the purity before a final offer. See how to perform an acid test at home and how to check for real gold coins.