---
title: "Gold hallmarks: what 375, 585, 750 and 916 mean on your jewellery"
description: "What 375, 585, 750 and 916 mean on gold, how a UK gold hallmark differs from a 9K or 18K stamp, and the marks that mean plated rather than solid gold."
canonical: "https://assaypost.co.uk/guides/gold-hallmarks-375-585-750-and-916"
published: "2026-09-26"
modified: "2026-09-26"
language: "en-GB"
publisher: "Assaypost"
---

# Gold hallmarks: what 375, 585, 750 and 916 mean on your jewellery

Written at the Assaypost bench, checked before publication. Published 26 September 2026.

**The short answer:** The number in a gold hallmark is the gold content in parts per thousand. 375 is 9 carat, 585 is 14 carat, 750 is 18 carat and 916 is 22 carat; 990 and 999 are the two fine gold standards. In a UK hallmark that number sits in a cut-cornered surround beside a sponsor's mark and an assay office mark, and it means an assay office has tested the piece. A bare 375, 18K or 750 with no assay office mark beside it is the maker's own claim. Marks such as GP, RGP, HGE, GF or 18KGP mean plated or rolled gold, not solid gold, whatever carat figure they carry.

## What the number in a gold hallmark says

Carats count in twenty-fourths and hallmarks count in thousandths. Pure gold is 24 carat, so 9 carat is nine parts in twenty-four, and nine divided by twenty-four is 0.375: that is where the 375 on a 9ct ring comes from. Every figure in the table below is the same sum done for a different carat, with the result rounded to the standard the assay offices test to.

**UK gold standards: the hallmark figure and the carat it corresponds to**

| Hallmark figure | Carat | Gold in 1,000 parts, at least | Where you usually see it |
| --- | --- | --- | --- |
| 375 | 9ct | 375 | The commonest British gold: wedding bands, signet rings, chains, lockets, charms |
| 585 | 14ct | 585 | Imported jewellery and much continental and American gold; some British pieces after 1932 |
| 750 | 18ct | 750 | Engagement and fine rings, better watch cases, much white gold |
| 916 | 22ct | 916 | Traditional British wedding rings, and gold from South Asia and the Middle East |
| 990 | Just under 24ct | 990 | A fine gold standard, seldom seen on jewellery |
| 999 | 24ct | 999 | Fine gold, mostly on bars and coins |

Two of the figures look slightly off, and both are deliberate. Fourteen twenty-fourths is 583.3, but the UK standard is 585, set a little above the arithmetic. Twenty-two twenty-fourths is 916.67, and the standard behind the 916 punch is 916.6. In both cases a hallmark is a floor: it certifies that the gold content is at least the figure shown, and a piece may test slightly above it.

The colour of the gold tells you nothing about the number. White gold, yellow gold and rose gold of the same carat carry the same hallmark, because the difference is in the other metals in the alloy: more copper for rose, palladium or nickel for white. A white 18ct ring is 750 like a yellow one, and most white gold is also rhodium-plated, which is why an old white ring can look faintly yellow where the plating has worn through.

## A UK gold hallmark, a foreign stamp, and the difference

The number alone is not the hallmark. A full UK hallmark on gold has three compulsory parts, usually struck in a short row: the sponsor's mark (initials in a shaped shield), the fineness figure in its surround, and the mark of the assay office that tested it. Optional marks, a crown and sometimes a date letter, may stand beside them. The row is the proof; any one part of it on its own is not.

- **A crown** beside the number is the traditional symbol for gold. It is optional, and its presence confirms what the number already says rather than adding to it.
- **A leopard's head** is London, **an anchor** is Birmingham, **a rose** is Sheffield and **a three-towered castle** is Edinburgh. If one of these is there, a UK assay office tested the piece.
- **A pair of scales**, with the fineness figure inside it or struck beside it, is the Common Control Mark of the Hallmarking Convention, struck by an assay office in a member country. The UK recognises it, so the piece has been independently tested even though the marks look foreign.
- **A number with none of the above**, whether 375, 585, 750, 9K, 14K or 18K, is the manufacturer's own claim. Most are right. It is still only a claim, and it is confirmed by testing before anybody should rely on it.

Order is less fixed than people expect. Birmingham Assay Office describes the usual modern sequence as sponsor's mark, then fineness, then office, but on a narrow ring shank or a chain tag the marks may be split, stacked or struck in a different order. What matters is that all three are present, not which comes first. The [glossary](https://assaypost.co.uk/glossary) has a short entry for each kind of mark if a term here is new to you.

The surround is part of the mark and not decoration. Silver's fineness sits in an oval, platinum's in a shape like a little house, and palladium's in three joined ovals (a trapezium on pieces marked in 2009), while gold's has its corners cut off. On a worn piece where the figure itself is hard to read, the outline that is left can still tell you which metal the assay office found.

## Older gold: carat figures, 12ct and 15ct, and what they date

Gold hallmarked before the modern system does not always show a three-figure number. Older 18ct and 22ct pieces commonly carry the carat itself, 18 or 22, beside a crown. The lower standards arrived later: the Goldsmiths' Company Assay Office records that 9, 12 and 15 carat gold were introduced in 1854, marked with figures stating their fineness, and that in 1932 the 12 and 15 carat standards were withdrawn and 14 carat took their place.

That gives a seller a free dating clue. A British 15ct or 12ct hallmark puts the piece between 1854 and 1932, which is Victorian, Edwardian or early twentieth-century work: exactly the period where a brooch, a locket or a gem-set ring can be worth more to a collector than its gold. A 14ct British hallmark, by the same logic, is 1932 or later.

**Gold standards that tell you roughly when a British piece was marked**

| What the mark shows | What it tells you about date |
| --- | --- |
| 15ct or 12ct with a British assay office mark | Hallmarked between 1854 and 1932, when those standards existed |
| 9ct with a British assay office mark | 1854 or later |
| 14ct or 585 with a British assay office mark | 1932 or later |
| A date letter | The year of hallmarking, once read with its office, typeface and shield: see the date letters guide |
| A plain three-figure number with no crown and no date letter | Very often 1999 or later, when the traditional symbols and the date letter became optional |

The last row is a tendency rather than a rule, because plenty of makers still ask for the crown and the date letter. The [date letters guide](https://assaypost.co.uk/guides/hallmark-date-letters-how-to-date-silver-and-gold) explains how to read the letter itself, and why it gives the year of hallmarking rather than the year the piece was made.

## Marks that mean plated, rolled or filled, not solid gold

The commonest mistake with gold marks is to read a carat figure inside a plating mark as a hallmark. The figure describes the thin layer of gold on the outside, and the letters beside it say that is all there is. None of these is an assay office mark, and none of them was put there by anyone who tested the piece.

**Stamps that look like gold marks but describe a coating**

| Stamp | What it means | What is underneath |
| --- | --- | --- |
| GP, GEP, 18KGP, 14KGP | Gold plated or gold electroplated. The carat is the plating's | Base metal, usually brass or copper alloy |
| HGE, HGP | Heavy gold electroplate. Thicker plating, still plating | Base metal |
| RG, RGP | Rolled gold, or rolled gold plate: a gold sheet bonded to a base-metal core | Base metal |
| GF, 1/20 12K GF, 1/10 10K GF | Gold-filled: a layer of gold bonded to the outside | Base metal, with a thicker layer than plating |
| 925 with a gold colour | Silver, gilded. Often called vermeil | Sterling silver |

18KGP is the one that catches most people, because the first three characters look exactly like an 18ct stamp and the last two are easy to miss under a worn surface. Read the whole stamp, not the first half of it. If the letters P, GP, E, F or R follow the carat, you are looking at a coating. The [guide to plated, rolled and filled gold](https://assaypost.co.uk/guides/plated-rolled-gold-filled-and-vermeil) explains how each of these is made and why none of them is gold through.

## Where the marks hide on rings, chains, earrings and watches

1. **Rings**: Inside the shank, usually at the back opposite the stone or the widest part. Resized rings sometimes lose part of the row where a piece was cut out or added.
2. **Chains and bracelets**: On a small flat tag beside the clasp, on the clasp itself, or on the end rings. A mark on the clasp alone tells you about the clasp; the chain is confirmed by testing.
3. **Pendants and lockets**: On the bail, the loop the chain passes through, or on the back or inside edge of a locket.
4. **Earrings and small charms**: Often nothing at all. Gold articles under 1 g are exempt from hallmarking, so a pair of plain studs with no mark is normal.
5. **Watches**: Inside the case back, not on the dial. A gold case can hold a steel movement, and a gold-filled case is often stamped to look like a solid one; the [gold watches page](https://assaypost.co.uk/what-we-buy/gold-watches) covers what to look for.

A phone camera held close in daylight reads most of these better than the eye does. Rest the piece on something pale and plain, let the light fall across the mark rather than straight onto it so the edges throw a shadow, and take two or three pictures at slightly different angles. A photograph that a person can zoom into is worth more than a written description of what the mark looks like.

## Seller risks and exceptions with gold marks

- 22ct gold stamped 916 abroad sometimes tests lower than the stamp. A UK hallmark is a tested minimum; a foreign 916 stamp is not, and the tested figure is the one that counts.
- A worn or partly polished-out hallmark still counts where enough of it can be read, but the less of it that survives, the more the identification rests on testing.
- A hallmark on a replaced clasp, or on a marked fragment soldered into an unmarked piece, describes only that part. Testing is done on the body of the item, not only where the mark is.
- The hallmark covers the metal, not what is set in it. A 750 ring with a large stone is 750 gold plus a stone, and the stone is not gold; the [guide to stones, clasps and what is not metal](https://assaypost.co.uk/guides/stones-clasps-and-what-is-not-metal) covers what is left out of the weight.
- Hollow gold is marked exactly like solid gold. A light, hollow bangle and a heavy, solid one can carry an identical row of marks.
- You do not need a hallmark to sell your own gold. The Hallmarking Act restricts how a business may describe an unhallmarked article when it supplies or offers it, subject to exemptions such as the minimum weights above; it does not stop a private person selling their own jewellery. An unmarked piece is tested before anything is said about its metal.

## When not to use the scrap route for marked gold

A gold mark tells you the alloy. It does not tell you whether the piece is worth more whole. A signed or maker-marked jewel, a Victorian 15ct brooch, an Art Deco ring or a working gold watch can each be worth considerably more to a collector or a specialist dealer than as metal, and the right route for those may be an auction house.

> **Send photographs of the marks first**
>
> Send close photographs of the marks on WhatsApp or through the [photo estimate](https://assaypost.co.uk/photo-estimate) page and a person will tell you what they suggest: which pieces look hallmarked, which carry only a maker's stamp, which are plated, and which look old or fine enough to be seen by a specialist before anything is posted. It is free and commits you to nothing. If you would rather send the lot, you can [request a postal pack](https://assaypost.co.uk/postal-pack) instead.

## Questions sellers ask

### What does 375 mean on gold?

It means 9 carat gold: at least 375 parts gold in every 1,000 parts of the alloy, which is nine twenty-fourths. With a UK assay office mark beside it, an assay office has tested it. On its own, it is the maker's claim and is confirmed by testing.

### Is 585 gold 14 carat?

Yes. 585 is the millesimal figure for 14 carat gold. The UK standard is set at 585, slightly above the exact fourteen twenty-fourths, so a hallmarked 585 piece is at least that fine.

### My ring says 18K but has no other marks. Is it real gold?

It may well be, but 18K on its own is a manufacturer's stamp rather than a hallmark, so nobody independent has tested it. Check the stamp does not continue with GP, GF or RGP, which would mean plated or filled. Then have it tested; a stamp is where identification begins, not where it ends.

### Why does my gold chain have no hallmark?

Gold articles under 1 g are exempt from hallmarking, and on a heavier chain the mark is often on a small tag near the clasp rather than on the links. Many imported chains carry only a maker's stamp. An unmarked chain is identified by testing and is nothing to worry about.

### Does white gold have a different hallmark from yellow gold?

No. White, yellow and rose gold of the same carat carry the same fineness figure. The colour comes from the other metals in the alloy, not from the amount of gold.

### What does 916 mean on gold?

22 carat gold, at least 916.6 parts in 1,000 under the UK standard. It is the traditional standard for British wedding rings and for much gold from South Asia and the Middle East. Foreign-stamped 916 is sometimes lower when tested, which is why it is checked rather than taken on trust.

## Sources

1. [Assay Offices of Great Britain — Hallmarking guidance notes (November 2022): compulsory and optional marks, approved finenesses and exemption weights](https://assets.publishing.service.gov.uk/media/63a333b9d3bf7f37654767e0/hallmarking-guidance-notes.pdf) (accessed 26 September 2026)
2. [The Goldsmiths' Company Assay Office — History of hallmarking: 1854 and 1932 gold standards](https://www.assayofficelondon.co.uk/about-us/history-of-hallmarking) (accessed 26 September 2026)
3. [The Goldsmiths' Company Assay Office — UK hallmarks: compulsory and optional marks](https://www.assayofficelondon.co.uk/hallmarking/uk-hallmarks) (accessed 26 September 2026)
4. [Birmingham Assay Office — How to read a UK hallmark: a beginner's guide](https://www.theassayoffice.co.uk/how-to-read-a-uk-hallmark-a-beginners-guide/) (accessed 26 September 2026)
5. [The Goldsmiths' Company Assay Office — UK and Convention marks](https://www.assayofficelondon.co.uk/other-services/imports-and-exports) (accessed 26 September 2026)
6. [legislation.gov.uk — Hallmarking Act 1973, section 1: prohibited descriptions of unhallmarked articles](https://www.legislation.gov.uk/ukpga/1973/43/section/1) (accessed 26 September 2026)

## Related

- [Reading UK hallmarks on gold, silver, platinum and palladium](https://assaypost.co.uk/guides/uk-hallmarks-and-fineness-guide)
- [Silver hallmarks: telling sterling from Britannia, continental silver and plate](https://assaypost.co.uk/guides/silver-hallmarks-sterling-britannia-and-plate)
- [Hallmark date letters: how to date a piece of silver or gold from its marks](https://assaypost.co.uk/guides/hallmark-date-letters-how-to-date-silver-and-gold)
- [Gold plated, rolled gold, gold-filled and vermeil compared](https://assaypost.co.uk/guides/plated-rolled-gold-filled-and-vermeil)
- [How to test gold at home: which checks mean something, and which will damage it](https://assaypost.co.uk/guides/how-to-test-gold-at-home)
- [Sell gold](https://assaypost.co.uk/sell-gold)
- [Glossary](https://assaypost.co.uk/glossary)

## Start with photographs

- [Send a photo on WhatsApp](https://wa.me/447369296063?text=Hello.%20I've%20been%20reading%20your%20guides%20and%20I've%20got%20some%20pieces%20I%20can't%20identify.%20Sending%20photos%20now.)
- [Request a prepaid label](https://assaypost.co.uk/postal-pack)
- Telephone [07369 296063](tel:+447369296063), 6am to 10pm, seven days a week