Hallmarks and stamps
What the small marks inside a ring mean, which ones the law requires, and which ones mean a piece is not solid gold.
Key points
- A fineness mark such as 14K or 585 states how much gold the metal contains.
- UK law requires gold to be hallmarked by an assay office, and US law requires no fineness mark.
- Stamps such as GF, GP, HGE and Vermeil mean gold filled or gold plated metal.
Most gold jewelry carries at least one small mark, usually inside a ring band or on a clasp. The rules for those marks differ from country to country.
Fineness marks
A fineness mark states how much gold the metal contains. American pieces usually show the karat: 10K, 14K or 18K. European pieces, and many newer American ones, show parts per thousand instead: 417 for 10k, 585 for 14k and 750 for 18k. Platinum is marked PT950, PLAT or similar.
A P after the karat, as in 14KP, stands for plumb gold: the maker states that the metal is at least the full 14 karats.
Maker's marks
In the United States no fineness mark is required. But under the National Gold and Silver Stamping Act, a maker, dealer or importer who stamps a mark such as 14K must put its name or its U.S. trademark, registered or applied for, next to it and at least as large, so a buyer knows who stands behind the claim. Pieces made before this rule was added in 1961 may lack one.
Hallmarks
In Britain and several other countries, hallmarking is a legal requirement. In the UK, any item sold as gold must be hallmarked unless the gold in it weighs less than 1 gram. An independent assay office tests it and strikes three compulsory marks: the sponsor's mark of the maker or importer, the fineness, and the mark of the assay office.
The United States has no government assay system, so an American fineness mark is the maker's own claim.
Marks that mean "not solid gold"
Some marks look like gold marks but describe something else:
- GF, or a mark such as 1/20 12K GF: gold filled, a layer of gold bonded to a base metal core.
- GP, GEP or HGE: gold plated or electroplated, a thin surface layer.
- Vermeil: gold plating over sterling silver.
These pieces can look like solid gold when they are new, but they are priced very differently and wear through over time.
Where to look
On rings, look inside the back of the band. On chains and bracelets, look on the clasp or on the small tag beside it. On earrings, look on the post or the back. A loupe helps, since the marks are often less than a millimeter tall.
Filed under Metals · October 23, 2026
