Every piece of precious metal sold in the United Kingdom above a certain weight must carry a hallmark. It is not a maker’s decoration and not a marketing claim — it is an independent test, carried out by an assay office that has no interest in the sale, and it is required by the Hallmarking Act 1973.
It is the only guarantee of metal purity a buyer gets, and it is worth two minutes of your attention.
What a UK hallmark consists of
Three marks are compulsory. Together they answer three questions: who made it, what it is made of, and who checked.
| Mark | What it tells you |
|---|---|
| Sponsor’s mark | Who submitted the piece for testing — the maker, manufacturer or the business selling it. Usually initials inside a shaped surround, and unique to that registrant. |
| Fineness mark | How much precious metal the piece contains, in parts per thousand. 925 means 925 parts silver in every 1,000. |
| Assay office mark | Which office carried out the test. Each has its own symbol. |
A date letter and the older pictorial fineness symbols may also appear, but since 1998 they have been optional. Their absence says nothing about quality.
The four UK assay offices
| Office | Symbol |
|---|---|
| London | Leopard’s head |
| Birmingham | Anchor |
| Sheffield | Rose |
| Edinburgh | Castle |
Fineness numbers
| Metal | Mark | Meaning |
|---|---|---|
| Silver | 925 | Sterling silver. 92.5% pure silver, the balance usually copper for strength. |
| Gold | 375 | 9 carat — 37.5% gold. Hard-wearing, the usual British choice for everyday chains. |
| Gold | 585 | 14 carat — 58.5% gold. Richer colour, still hard enough for daily wear. |
| Gold | 750 | 18 carat — 75% gold. Deeper colour, softer metal. |
| Gold | 916 | 22 carat — 91.6% gold. Very soft, mostly used for wedding bands. |
| Platinum | 950 | 95% platinum. Denser than gold, naturally white, never needs re-plating. |
When a hallmark is not required
Below certain weights the law does not require hallmarking, because the marks would damage the piece. According to the Assay Office, items are exempt below 1.0 g of gold, 7.78 g of silver and 0.5 g of platinum.
So a fine silver pendant may legitimately carry no hallmark. That is not a warning sign. A heavy gold chain with no hallmark is a different matter — ask the seller why.
Gold vermeil and plating are not the same thing
Two terms get used loosely, and the difference is money.
Gold vermeil is a layer of gold over solid sterling silver. The base metal is precious, so a vermeil piece heavy enough to qualify carries a silver hallmark. It wears far better than plating and can be re-finished.
Gold plated usually means a thin layer of gold over brass or another base metal. There is no precious metal underneath and no hallmark, because there is nothing to hallmark.
We say which is which on every product page.
Where to look on the piece
On a ring, inside the band. On a chain or bracelet, on the clasp or on a small tag beside it. On earrings, on the post or the back of the fitting. The marks are small — a phone camera at maximum zoom usually reads them better than the eye.
If something looks wrong
Write to us. Every piece we sell that requires a hallmark carries one, and we will tell you which office tested it.