Symbols Stamped on Jewellery: What Every Mark Means

Turn a ring over and there's usually something stamped inside the band. Three numbers, a couple of letters, sometimes a tiny animal.

Most people never look. The ones who do usually can't read it.

Those marks are the only part of a piece of jewellery that has to tell the truth. Everything else, from the description to the photograph to the price, is written by whoever is selling it. The stamp is the metal declaring what it actually is.

Below is what every mark means, how to read a full British hallmark, and what to do when there's no stamp at all.

Jump to:

• What a Stamp Is Actually Telling You
• The Complete Stamp Key
• Gold Marks Explained
• Silver Marks Explained
• Platinum, Palladium and Titanium
• Plating Marks: GP, GEP, HGE and GF
• How to Read a Full UK Hallmark
• Maker's Marks
• Can Jewellery Be Identified If It's Stolen?
• What If There's No Stamp?
• What Our Pieces Are Marked
• FAQs

What a Stamp Is Actually Telling You

A mark on jewellery does one of four jobs. Once you know which is which, most of the confusion goes.

It tells you the metal and its purity. This is the number: 925, 750, 375. It's a fineness mark, and it says how many parts per thousand of the piece are the precious metal.

It tells you who made it. A maker's mark, or sponsor's mark: initials or a small symbol identifying whoever submitted the piece.

It tells you who tested it. On a British piece, an assay office mark, a small symbol showing which office independently verified the metal.

It tells you when. A date letter, optional in the UK since 1999 but still applied by many.

Anything else (a serial number, an engraving, a design registration) is extra, and usually specific to one maker.

One thing worth being clear about up front: a fineness number describes solid metal, not a coating. A piece stamped 750 is 18 carat gold all the way through. Plated pieces are marked differently, and we'll come to those.

The Complete Stamp Key

The full list, grouped by what you're likely holding.

Gold

Silver

Platinum and other metals

Coatings and stones

The one that catches people out: SS. It can mean sterling silver, and it can mean stainless steel, and those are wildly different things. Context decides it: a delicate ring is probably sterling, a heavy watch bracelet is probably steel. If it matters, look for a 925 alongside it. Sterling almost always carries the number too.

And the second one: 925 on a gold-coloured piece. That doesn't mean it's silver pretending to be gold. It means gold vermeil, real gold over a solid sterling silver base, so it carries the hallmark of the metal underneath rather than the gold on the surface. Our guide to 18K gold vs gold vermeil explains how that's built.

Gold Marks Explained

Gold is measured in carats, and a carat is one twenty-fourth. So 18 carat gold is eighteen parts gold in twenty-four, which is 75%, which is why it's stamped 750. Every gold number works the same way.

The British and American difference is worth knowing, because it causes real confusion:

• In Britain, gold purity is carat, spelled with a C, and marked 9ct, 18ct.
• In America, gold purity is karat, spelled with a K, and marked 14K, 18K.
• Gemstone weight is carat in both, spelled with a C.

So in the UK, "carat" does double duty: it means gold purity and diamond weight, and you tell them apart by what they're attached to. A 0.5 carat diamond in an 18 carat gold ring is a perfectly normal thing to write, and both words are correct.

Higher isn't automatically better. Pure gold is very soft, which is why 24 carat is rarely used for anything worn daily. 9 carat is harder and far more scratch-resistant; 18 carat is the usual compromise between richness of colour and durability. What the number really tells you is value and softness, not quality.

On white gold specifically, the mark tells you the gold content and nothing about the colour. There's no separate white gold hallmark, which trips people up constantly. What is white gold covers why, and what the rhodium on top is doing.

Silver Marks Explained

925 is the one you'll see almost every time. Sterling silver: 92.5% silver, 7.5% other metals, usually copper. Pure silver is too soft to hold a shape, so the alloy is what makes it wearable.

958 is Britannia silver, a higher standard introduced in 1697 and still used. 800 to 835 turns up on continental European pieces and is below sterling, perfectly legitimate but simply less silver.

A 925 stamp is not proof on its own. It's stamped by the maker and can be applied dishonestly. A full British hallmark, with an assay office mark beside the number, is independently verified and is the stronger guarantee. What 925 means goes through how to check a piece properly, including the tests you can do at home.

Platinum, Palladium and Titanium

Platinum is marked PT, PLAT, or a fineness number, and 950 is the standard, meaning 95% platinum. It's denser and rarer than gold, and unlike white gold it's white all the way through with nothing to re-plate.

Palladium is marked PD or PALL. Lighter than platinum, from the same metal family, and increasingly used in white gold alloys.

Titanium and tungsten aren't precious metals, so they aren't hallmarked and carry no fineness number. TI or TUNG is a material description rather than a purity guarantee.

Stainless steel is the same. It can't be hallmarked, because hallmarking law covers precious metals only. That's not a mark of lower quality, it's a different category. Steel doesn't tarnish or corrode, which is why it outlasts most precious metals in daily wear.

Plating Marks: GP, GEP, HGE and GF

These are the marks that describe a coating rather than the metal itself, and they're the ones most likely to be misread as a purity mark.

• GP and GEP. Gold plated and gold electroplate. A thin gold layer over a base metal. No minimum thickness behind either term.
• HGE and HGP. Heavy gold electroplate. Thicker than standard, though "heavy" isn't consistently defined.
• RGP. Rolled gold plate, an older mechanical bonding method.
• GF. Gold filled. Usually written as a fraction like 1/20 12K GF, meaning the gold is a stated share of total weight. More durable than plating, less than solid.

None of these is a hallmark. They're maker-applied descriptions, they aren't independently tested, and they tell you nothing about the base metal underneath, which is the part that decides how a plated piece ages. What gold plated means goes through the two numbers that actually matter.

How to Read a Full UK Hallmark

This is where Britain does something most countries don't, and it's the strongest tool you have for checking a piece.

Hallmarking here is compulsory and independent. A precious metal item sold in the UK above a certain weight must be tested by an Assay Office before it can legally be described as gold, silver, platinum or palladium. The maker doesn't get to self-declare. It's been running in some form since 1300, which makes it one of the oldest consumer protection systems anywhere.

The weight thresholds, below which hallmarking isn't required:

• Gold: 1 gram
• Silver: 7.78 grams
• Platinum: 0.5 grams
• Palladium: 1 gram

A full hallmark has three compulsory parts, usually struck in a row:

1. The sponsor's mark. Two or more letters in a shaped surround, identifying who submitted the piece. Every sponsor's mark is registered and unique.

2. The fineness mark. The number (375, 925, 950) inside a shape that indicates the metal. Gold, silver, platinum and palladium each get a different outline.

3. The Assay Office mark. A small symbol showing where it was tested:

• A leopard's head for London
• An anchor for Birmingham
• A rose for Sheffield
• A castle for Edinburgh

Two optional marks you'll often see alongside: a date letter, which changes annually and tells you the year of hallmarking, and a traditional fineness symbol, such as a crown for gold, Britannia for the higher silver standard, or a lion passant for sterling.

How to use this practically. If you're buying something second-hand and it's described as solid gold or sterling, look for the assay office symbol, not just the number. A lone 925 with nothing beside it is a maker's claim. A 925 next to a leopard's head has been independently tested. On a piece over the weight threshold, being sold as precious metal, no hallmark at all is a fair question to raise before you buy.

Maker's Marks

A maker's mark tells you who made or submitted a piece, and on older jewellery it can be worth more than the metal.

On British pieces it's the sponsor's mark, and it's registered with an Assay Office, so an unfamiliar set of initials can usually be traced. That's how antique dealers date and attribute pieces, and it's why a mark from a well-regarded workshop can add substantially to value.

On modern pieces it's usually a logo or brand name, which is a trade mark rather than a hallmark. Useful for identifying the maker, no guarantee of metal content on its own, since the fineness mark does that job.

Worth being straight about this, since it's a distinction sellers sometimes blur: a brand logo stamped on a piece tells you who made it. It doesn't tell you what it's made of, and it isn't an equivalent of an assay office mark. Both are useful. They're answering different questions.

Can Jewellery Be Identified If It's Stolen?

A question that comes up far more than you'd think, and the honest answer is mostly no, though there are some things you can do about it.

Hallmarks don't identify individual pieces. This is the part people get wrong. A hallmark says what the metal is, who submitted it and where it was tested. It doesn't carry a unique number for your particular ring. Ten thousand identical pieces from the same maker carry identical marks.

Most jewellery has no serial number at all. Watches usually do, often on the case back or between the lugs, and that genuinely helps. Fine jewellery over a certain value sometimes carries one, and diamonds above roughly a carat are often laser-inscribed on the girdle with a certificate number, readable under magnification. Everyday jewellery generally has nothing.

And the harder truth: precious metal gets melted. A stolen chain often stops existing as a chain within days, which is why recovery rates are low and why identification usually matters more for insurance than for getting the piece back.

What actually helps, and it's worth ten minutes:

• Photograph everything you'd miss, including the marks, with something for scale.
• Keep receipts and valuations, and get anything significant valued for insurance.
• Note any inscription. A personal engraving is far more identifying than a hallmark, because it's unique to your piece.
• Register the valuable items on a national property database. Your insurer or local police force can tell you which one they work with.
• Consider having something discreetly marked if a piece is genuinely valuable. A jeweller can advise on what won't damage it.

If you've been burgled, report it to the police and to your insurer, and give them the photographs and any inscription wording. That combination does more than a hallmark ever will.

What If There's No Stamp?

An unmarked piece isn't necessarily fake. There are several innocent explanations.

It might be under the weight threshold. A fine chain or a small stud can legally be sold as gold in the UK without a hallmark if it's light enough.

The mark may have worn away. Hallmarks are shallow, and decades of wear can rub one almost flat, especially on a ring band, which takes constant abrasion. A jeweller's loupe often finds what the naked eye can't.

It might be older, or from a country with no hallmarking system. Plenty of legitimate antique and imported jewellery carries no mark.

It might be resized. Ring sizing sometimes removes the section of band carrying the hallmark, and a good jeweller will note this.

Or it might not be what it's described as. If a piece is heavy enough to require a mark, is being sold to you as precious metal, and doesn't have one, that's worth asking about before money changes hands.

Two things you can do yourself. A magnet is a quick negative test: gold, silver, platinum and palladium aren't magnetic, so a piece that jumps to a magnet isn't solid precious metal (though non-magnetic doesn't prove it is). And for silver specifically, tarnish is a good sign: genuine sterling tarnishes, and something sold as silver that never does is usually plated. How long sterling silver lasts covers that in more detail.

What Our Pieces Are Marked

Worth saying plainly where we sit, since this page is about reading what a piece declares about itself.

Our sterling silver range is genuine 925, and carries a 925 stamp. Applying the test set out above honestly: that's a fineness stamp rather than a full assay office hallmark, and the reason is the weight threshold. Silver only has to be hallmarked above 7.78 grams, and most jewellery at this scale sits under it. A 925 stamp is the normal and correct marking for pieces in that range. It behaves like sterling too: it will tarnish eventually and polish straight back, because the silver goes all the way through.

Most of our range is built on a solid 316L stainless steel core, finished in rhodium for silver-tone pieces or real 18 carat gold for gold-tone. Steel isn't a precious metal, so it can't be hallmarked and carries no fineness mark, which is the law rather than a shortcut. What you get instead is a finish that's waterproof, sweatproof and heatproof, on a core that can't rust, tarnish or corrode underneath it. The one exception worth knowing is chlorine and salt water, which are aggressive on any gold surface, so pools and the sea are the two places worth taking a gold-finished piece off. How to clean gold jewellery covers the rest.

We also make gold vermeil, real 18 carat gold over solid sterling silver, which is why those pieces carry a 925 mark despite being gold-coloured.

Three constructions, three different things a mark can tell you, and every product page says which is which.

FAQs

What do the symbols stamped on jewellery mean?

Most marks do one of four jobs: state the metal's purity as a number like 925 or 750, identify the maker, show which assay office tested it, or give the year. A fineness number describes solid metal all the way through, while letters like GP or GEP describe a coating over a base metal.

What does 925 mean on jewellery?

Sterling silver: 92.5% pure silver with 7.5% other metals, usually copper. On a gold-coloured piece, 925 means gold vermeil, because the mark refers to the sterling silver base underneath the gold.

What does 750 mean on jewellery?

18 carat gold, meaning 75% pure gold alloyed with other metals. It's solid gold throughout, not a coating. The equivalent marks are 375 for 9 carat, 585 for 14 carat and 916 for 22 carat.

What does 375 mean on jewellery?

9 carat gold, 37.5% pure. It's the most common gold standard in Britain, harder and more scratch-resistant than higher carats, and less expensive because there's less gold in it.

What's the difference between carat and karat?

In Britain, carat with a C means both gold purity and gemstone weight, and you tell them apart by context. In America, karat with a K means gold purity and carat with a C means gemstone weight. A 0.5 carat diamond in an 18 carat gold ring is correct British usage.

What do GP, GEP and HGE mean?

Gold plated, gold electroplate and heavy gold electroplate. All three describe a gold coating over a base metal rather than solid gold, none has a guaranteed minimum thickness, and none is a hallmark. They're maker-applied descriptions, not independently tested.

Is SS sterling silver or stainless steel?

It can be either, which is exactly the problem. Sterling silver almost always carries 925 as well, so if you only see SS with no number, it's more likely stainless steel. Weight and context help, since steel is used for heavier, more industrial pieces.

Does jewellery have a serial number if it's stolen?

Usually not. A hallmark identifies the metal, the maker and the assay office, but not your individual piece, so identical items carry identical marks. Watches often have serial numbers, and diamonds above about a carat are frequently laser-inscribed, but most everyday jewellery has nothing unique on it. Photographs, valuations and any personal engraving are far more useful for identification.

What is a maker's mark?

A stamp identifying who made or submitted a piece. On British hallmarked jewellery it's a registered sponsor's mark of two or more letters, which can be traced through the Assay Offices. On modern jewellery it's often a brand logo, which identifies the maker but says nothing about metal content.

What does it mean if my jewellery has no stamp?

Not necessarily anything bad. It may be under the weight threshold for compulsory hallmarking, the mark may have worn away, it may be antique or imported from a country without a hallmarking system, or it may have been lost during resizing. But an unmarked piece heavy enough to need a hallmark, sold to you as precious metal, is worth questioning.

Where to Go From Here

The marks on a piece of jewellery are the one part of it that has to be honest. Learn six or seven of them and you can walk into any second-hand shop and know what you're looking at.

The short version: numbers mean solid metal, letters usually mean a coating, and a British assay office symbol means somebody independent checked.

If you want to go deeper on a particular metal, what 925 means covers sterling silver, what is white gold covers the carats and hallmarks on white gold, and what gold plated means covers everything with a coating on it.