A Guide on Jewelry Hallmarks
So you’ve noticed some numbers or possibly letters stamped on your piece. The numbers refer to the metal while letters are typically the makers hallmark. While some hallmarks like 14k are obvious, others like 1/20 14k may not be. Here's a simplified chart to make it easy to understand exactly what all those numbers and letters mean.
| Description | Mark | Metal |
|---|---|---|
| Sterling silver, denoted by 92.5% pure silver while the remaining 7.5% is copper. | .925 | Silver |
| Fine silver, 99.9%—less common in jewelry because of how soft silver is. Fine silver doesn’t hold its form as easily and is prone to being marred and scratched. | .999 | Silver |
| 41.7% gold while the remaining 58.3% are other metal alloys. | 10k | Gold |
| 58.5% gold while the remaining 41.5% are other metal alloys. | 14k | Gold |
| 75% gold while the remaining 25% are other metal alloys. | 18k | Gold |
| 91.6% gold while the remaining 8.4% are other metal alloys. | 22k | Gold |
| 100% pure gold--this is rarely seen in jewelry because gold is a soft metal meaning its easily scratched and doesn't hold a shape well. | 24k | Gold |
| 9k or 37.5% gold while the remaining 62.% are other metal alloys. | .375 | Gold |
| 14k or 58.5% gold while the remaining 41.5% are other metal alloys. | .585 | Gold |
| 18k or 75% gold while the remaining 25% are other metal alloys. | .750 | Gold |
| 90% platinum with the remaining 10% either iridium, cobalt, palladium, ruthenium, or sometimes copper or a mix of these metals. | PT900 | Platinum |
| 95% platinum with the remaining 5% either iridium, cobalt, palladium, ruthenium, or sometimes copper or a mix of these metals. | PT950 | Platinum |
| Denotes gold filled, or 1/20 (5%) gold often accompanied by whichever karat is being used. Ex: 12k GF or 14k GF | GF | Gold |
| Denotes gold plated, or 0.175 micron thickness of pure gold often accompanied by whichever karat is being used. Ex: 14k GP or 18k GP | GP | Gold |
Jewelry hallmarks can be a tad confusing especially because they differ in each country. Given each country regulates hallmarking differently, this is really no surprise. If you ever feel questionable about your piece, there are kits you can purchase to test the gold content or you may also take the piece to your local jeweler who likely can perform this test as well.
Jewelers also often have their own trademarked hallmark denoting their company or name that is accompanied by the metal content hallmark. So letters outside of the above listed chart are likely associated with the jeweler. Now you can rest easy knowing you can easily interpret what your ring's stamps are trying to tell you, or maybe not tell you if something's missing.
