Karat & hallmark guide
What the small stamps on gold, silver and platinum mean, how much precious metal each one stands for, and which marks mean an item is only plated.
Gold karats
A karat is one twenty-fourth part. 24 karat is pure gold, and 14 karat is 14 parts gold out of 24. Most pieces are stamped with either the karat (14K) or the purity in thousandths (585). Both mean the same thing.
| Karat | Number stamp | Gold content | Where you see it |
|---|---|---|---|
| 24K | 999 | 99.9% | Pure gold; bullion and some Asian jewelry |
| 22K | 916 | 91.7% | Gold Eagles, Krugerrands, sovereigns, Indian jewelry |
| 21K | 875 | 87.5% | Common in Middle Eastern jewelry |
| 18K | 750 | 75.0% | Fine jewelry and watches |
| 14K | 585 | 58.5% | The most common US jewelry karat |
| 10K | 417 | 41.7% | Class rings and lower-cost US jewelry |
| 9K | 375 | 37.5% | Common in UK and older European jewelry |
Some older American pieces stamped 14K were made slightly under 58.5%, which is why buyers test gold rather than relying on the stamp alone. You can value any karat with the gold melt calculator.
Silver marks
| Mark | Silver content | Standard |
|---|---|---|
| 9999 | 99.99% | Fine silver |
| 999 | 99.9% | Fine silver |
| 980 | 98% | Britannia silver |
| 958 | 95.84% | Britannia (older) |
| 950 | 95% | French / Peruvian |
| 935 | 93.5% | German / Scandinavian |
| 925 / Sterling | 92.5% | Sterling silver |
| 900 / Coin | 90% | Coin silver (US) |
| 875 / 84 | 87.5% | Russian silver |
| 835 | 83.5% | Continental silver |
| 830 | 83% | Scandinavian silver |
| 800 | 80% | Central European |
| 750 | 75% | Low-grade silver |
British sterling usually carries a lion passant (a walking lion) instead of the number 925. Value silver with the silver melt calculator.
Platinum marks
| Mark | Platinum content |
|---|---|
| 999 | 99.9% |
| 950 / PT950 / PLAT | 95.0% |
| 900 / PT900 | 90.0% |
| 850 / PT850 | 85.0% |
Marks that mean plated or filled
These stamps mean an item has only a thin layer of precious metal and should not be weighed as solid gold or silver.
| Mark | Meaning | Melt value |
|---|---|---|
| GF, 1/20 12K GF, 1/20 14K GF | Gold filled | A layer of gold bonded over brass. The gold is 5% or less of the total weight. |
| RGP | Rolled gold plate | Like gold filled but with an even thinner gold layer. |
| GP, GEP, HGE, HGP | Gold plated / heavy gold electroplate | A very thin electroplated gold layer. Not worth refining. |
| Vermeil | Gold over sterling silver | Valued for the sterling silver underneath; the gold layer is thin. |
| EP, EPNS, Silver plate | Electroplated silver | A thin silver layer over nickel silver or brass. Little melt value. |
| Nickel silver, German silver, Alpaca | No silver | Copper, nickel and zinc alloys that contain no silver at all. |