What gold hallmarks tell you
A gold mark usually states how much of the metal is pure gold, either in carats (karats in the US) or as a number out of 1,000. Marks may also show the maker, the place of assay and, in some systems, the year. Marks help, but they are not a guarantee of authenticity, since they can be damaged, copied or misapplied. If a piece is valuable, ask a qualified jeweler or assay office to test it.
Carat and fineness table
Pure gold is 24 carat. Common standards and their usual marks are:
| Carat | Fineness mark | Approximate gold content |
|---|---|---|
| 9ct | 375 | 37.5% |
| 10k | 417 | 41.7% |
| 12ct | 500 | 50% |
| 14ct | 585 | 58.5% |
| 15ct | 625 | 62.5% |
| 18ct | 750 | 75% |
| 22ct | 916 | 91.6% |
| 24ct | 999 | 99.9% |
In Britain, 9, 14, 18, 22 and 24 carat are used now, while 12 and 15 carat were used in earlier periods. In the United States, “K” or “KT” with a number is typical, and 10, 14 and 18 karat are very common.
UK hallmark parts
British gold hallmarks follow the same general layout as silver: a maker’s mark, a fineness or standard mark, an assay office mark and, traditionally, a date letter. The standard mark often appears as the carat number plus the fineness figure, for example “18” and “750”. The common assay office marks include a leopard’s head for London, an anchor for Birmingham, a crown for Sheffield (newer Sheffield marks use a rose) and a castle for Edinburgh. For the layout in more detail, see the matching section of our silver hallmarks guide.
Gold items over a minimum weight sold in the UK are generally required to be hallmarked. Check current rules with an assay office if this matters for a sale.
Crown marks
The crown has appeared on gold in several systems. In older English marks, a crown beside a number such as 18 or 22 was used as a gold standard mark. Sheffield’s assay mark is also a crown, and a crown appears in other national marks. Context matters, so identify the other marks on the piece before concluding what a crown means. Because meanings varied by country and date, consult a reference chart for the marks you see.
What 833 means
The number 833 indicates 83.3 percent gold, equal to 20 carat. It is seen on some continental European items rather than on standard British pieces. It does not mean the same as 585 or 750, so check the number against its country of origin.
Maker stamps
Maker marks are usually initials or a symbol registered with an assay office or used by a manufacturer. On antique pieces they can help narrow down the maker and date, but you will need a specialist reference or database to match them. An unrecognised stamp does not mean a piece is fake, since many small makers are poorly documented.
Rolled gold, gold-filled and plated marks
Several marks show that a piece is not solid gold:
- Rolled gold (RG, RGP): a layer of gold mechanically bonded to a base metal, generally thinner than gold-filled.
- Gold-filled (GF): a thicker bonded layer, typically marked with a fraction such as 1/20 14K.
- Gold plated (GP, HGE): a thin electroplated layer, which can wear through.
These pieces have some decorative value but are not worth the same as solid gold, and no quality mark means they cannot be assumed to be solid.
How to check a mark
- Clean gently and use a jeweler’s loupe in good light.
- Read all marks and note the country style.
- Compare the numbers to the table above.
- Test or assay the item if you are buying or selling, since stamps can be misleading.
- Judge the piece in context: style, construction and wear should fit the apparent age, as outlined in antique periods explained.
For wider buying advice, see how to start collecting antiques.
FAQ
What does a crown mean on a gold ring?
It may be an older English gold standard mark or an assay office mark, depending on the other marks and the date. Identify the other stamps to be sure.
What does 833 hallmark gold mean?
It means 83.3 percent gold, about 20 carat, and is found on some continental European items.
How to check a gold hallmark?
Read all marks under magnification, compare with a chart, and have the piece tested by a professional if value matters.
What does “rolled gold” mean?
A thin layer of gold bonded onto a base metal. It is not solid gold.