Gold Hallmarks Guide
How to read 375, 585, 750, 875, 916 and 999 stamps.
Gold hallmarks tell you how much real gold is inside a piece. The three-digit number is parts per thousand, and can be converted directly to karat and purity percentage.
Hallmark conversion table
| Stamp | Karat | Purity | Typical use |
|---|---|---|---|
| 999 | 24K | 99.9% | Bullion and investment products |
| 916 | 22K | 91.6% | Traditional high-purity jewelry |
| 875 | 21K | 87.5% | Regional high-karat jewelry |
| 750 | 18K | 75.0% | Fine and luxury jewelry |
| 585 | 14K | 58.5% | Everyday jewelry in many markets |
| 417 | 10K | 41.7% | Entry-level US jewelry |
| 375 | 9K | 37.5% | Common in UK/Australia |
Extra marks you may see
Maker's mark
Identifies the manufacturer or sponsor.
Assay mark
Shows the office that tested and certified purity.
Country mark
Can indicate national hallmarking system or standard.
Frequently asked questions
What are gold hallmarks?
Gold hallmarks are official marks stamped on jewelry to indicate purity and often origin, maker, or assay office information.
What does 750 hallmark mean?
750 means 75.0% pure gold, equivalent to 18K.
Is hallmarking required by law?
In many countries, hallmarking rules are regulated and enforced for consumer protection, but exact requirements vary by jurisdiction.