Hallmarks & Carats

What does 375 mean on gold? 9ct gold, 37.5% pure

375 on gold means 9 carat: 375 parts in every 1,000 are pure gold, and the other 625 are alloy metals such as silver, copper or zinc. It is the lowest gold standard a UK assay office will hallmark and the most common carat in British jewellery, from wedding bands and signet rings to chains and charm bracelets.

By Rocco Clayfield, trading as GoldPaid; the business incorporated as GOLDPAID LTD (company 17382540) on 5 August 2026 · Published · updated

What does 375 mean on gold?375 means 9 carat gold: 375 parts in every 1,000 are pure gold and the rest is alloy, usually silver and copper. The other UK gold standards are 585 (14ct), 750 (18ct), 916 (22ct), 990, and 999 (24ct). 575 and 373 are not UK standards; they are usually a worn or misread 585 or 375, and an XRF test settles which. A full UK hallmark also carries a sponsor’s mark and an assay office mark.

Found 375 on your piece? Send us a photo of it

Photograph the number stamped inside the ring or on the clasp, then the whole piece, and send both on WhatsApp. We will reply with what the mark means and a rough estimate of what we would pay. No obligation, and nothing needs posting.

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No WhatsApp? Call 07944 014111, 8am to 9pm.

Not sure what the mark says? Use the hallmark lookup. Final offers depend on inspection, item weight, purity, hallmarks, stones, non-gold components, condition and the live precious-metal market.

How pure is 375 gold?

375 is parts per thousand. Out of every 1000 units of the alloy by weight, 375 units are pure gold. That works out to 9 parts of gold in a 24-part system, which is where the "9 carat" name comes from. The other 625 parts are partner metals that give the alloy its colour, hardness and machinability.

UK gold fineness marks
MarkCaratPure gold
3759ct37.5%
58514ct58.5%
75018ct75.0%
91622ct91.6%
990990 gold99.0%
99924ct99.9%

A common 9ct yellow alloy is 37.5% gold with the rest mostly copper and silver and a little zinc. A 9ct white alloy uses palladium or nickel in place of some of the silver and copper to take out the yellow tone.

Why 9ct is so common in the UK

The UK is one of the few major markets where 9ct dominates the high street. In Italy or India most jewellery is sold at 18ct or 22ct. In Britain, 9ct sits in the sweet spot of price and durability and accounts for a huge share of jewellery sales.

That matters when you sell. A British jewellery box can hold several standards at once, so every piece is XRF-assayed and weighed on its own. Items that test at 375 are priced at 375, and anything that tests higher is priced at what it tests, not averaged down to the commonest mark.

Hardness and wear

9ct is harder than 18ct or 22ct because the partner metals (copper, silver, zinc, sometimes palladium) make the alloy stiffer. A 9ct band will resist denting and scratching better than a high-carat band of the same shape. That is why working hands often prefer 9ct for everyday rings.

The trade-off is colour. 9ct yellow is a paler, slightly cooler shade than 18ct yellow. Some buyers prefer the deeper warmth of higher carats. The colour preference is personal. The scrap economics are decided by the carat number, not the shade.

How 9ct sells at scrap

9ct is valued the same way as every other carat. The offer starts from the gold we measure, 0.375 of the weight for 9ct, valued against the live fine-gold market. The value per gram is lower than for higher carats only because there is less gold in each gram. How a tested weight and purity become an offer sets out the method.

Final offers depend on inspection, item weight, purity, hallmarks, stones, non-gold components, condition and the live precious-metal market.

Identifying 9ct quickly

  1. Find the inside of the shank or the clasp.
  2. Look for 375 in a small punch with cut corners, or 9 and .375 side by side on older British pieces.
  3. Check that the standard mark sits beside an assay office mark (leopard, anchor, rose or castle).
  4. Weigh the piece on a kitchen scale. Even a thin 9ct chain has noticeable heft for its size.
  5. If nothing readable is left, send it in. XRF says whether the alloy is genuinely 375 or something else.

When 9ct surprises you

A heavy 9ct curb chain or rope chain can hold more grams of gold than a small 18ct ring, because the weight matters as much as the purity. A 30 gram 9ct chain has 11.25 grams of pure gold. A 5 gram 18ct ring has 3.75 grams. The recovered yield difference is significant in favour of the chain. People are sometimes surprised that the "bigger but lower carat" piece outvalues the "smaller but higher carat" piece. Mass times purity is what matters.

Sending 9ct by post

9ct posts the same way as any other UK gold. WhatsApp 07944 014111 to start, request the prepaid Royal Mail Special Delivery label, and send any 9ct items in a padded envelope or small box. The XRF report shows the standard. Bank transfer follows acceptance. Decline is free return by tracked post. Your parcel travels on Royal Mail Special Delivery Guaranteed, tracked and signed for. Royal Mail cover may be available up to £2,500 depending on the postal method and cover level used. GoldPaid can confirm the appropriate postal option before you post. If the lot may be worth more than £2,500, tell us first and we can split it across more than one prepaid label at no charge. The full method is on the sell gold by post page.

What 9ct means for the offer you get

375 is the British workhorse. It is not glamorous on a carat-vanity scale, and the method of pricing it is no different: weight, tested purity, the live market. Nine carat is 37.5 per cent gold, so a 9ct piece holds roughly half the gold of an 18ct piece of the same weight. That is arithmetic rather than a judgement on the jewellery, and each item is set out on its own line in the written offer so you can see how the figure was reached. The method that turns a tested 9ct weight into an offer is written out in full.

Next step: have the mark checked against the metal

A hallmark records the standard a piece was assayed at. It does not tell you what the alloy measures now, what the piece weighs once stones and non-gold parts are set aside, or where the market sits today. Send a photo of the punches on WhatsApp and we will tell you what can reasonably be read from an image. Post the piece and it is XRF-tested on arrival, with a written offer showing the purity found, the weight and the figure for each piece. Decline it and the tracked return costs you nothing. Accept it and we aim to pay by Faster Payments within one working hour of your acceptance.

Send a photo on WhatsApp

Common questions

Is 9ct gold "real" gold?

Yes. It is 37.5% pure gold by weight, legally classed as gold under UK hallmarking.

Why is 9ct lighter in colour than 18ct?

There is less gold and more silver and copper or palladium in the alloy, so the yellow is paler.

Does 9ct tarnish?

The gold content does not tarnish. The copper and silver content can dull slightly on some 9ct yellows over decades. Polishing restores the colour.

Is 9ct stronger than 18ct?

Generally yes. The alloy is harder because of the higher base-metal content.

Can I sell a single broken 9ct chain?

Yes. Condition does not affect the recovered yield. Broken chains pay on the gold content.

Does 9ct white gold pay differently from 9ct yellow?

No. Same standard, same recovered gold per gram, same scrap figure at the same market level.

What does 9ct white gold look like under the rhodium?

A warm cream-white tone, slightly yellow. The rhodium plating gives it the bright cool white finish.

Is 9ct ever stamped "9k" instead of 375?

On US-imported pieces yes. The UK standard mark is 375. "9k" or "9kt" suggests foreign origin or an older UK stamp.

Not the question you had? The full GoldPaid FAQ covers the rest, from postal cover and ID checks to what happens if you decline the offer.

Related guides

Reference pages

UK-wide by post, no shop visit needed

Send a photo, get a free figure

Open WhatsApp, send a photo, and ask about the X-ray (XRF) testing, the postal cover, the timing or the return. Nothing leaves your hands until you have read the written offer.

Free prepaid label, usually sent within 30 minutes during working hours. Free tracked return if you decline. We aim to pay by Faster Payments within one working hour of acceptance.