In short
375 is 9 karat gold: 375 parts gold in 1,000, or 37.5% by weight. The other 62.5% is copper, silver and zinc. It is the everyday gold of the United Kingdom, Ireland, Australia and much of the Commonwealth, and it almost always arrives in the US on inherited or travel-bought pieces, because US rules do not allow anything under 10 karat to be sold as gold. At today's spot, the gold in a gram of 375 is worth $53.15, against $59.10 for 10k and $82.92 for 14k. A scrap buyer pays a share of that; a jeweler prices the piece on its craft, not its metal.
Contents
The number is a fineness, not a code
Gold purity is written two ways. Karats divide the metal into 24 parts: 9 karat is 9 parts gold in 24, which is 9 ÷ 24 = 0.375. Millesimal fineness writes the same fraction in parts per thousand: 375. The stamp systems map onto each other exactly, and once you know the conversion the whole family reads at a glance.
| Stamp | Karat | Gold by weight | Where it is standard | Gold value per gram today |
|---|---|---|---|---|
| 375 | 9k | 37.5% | UK, Ireland, Australia, NZ, South Africa | $53.15 |
| 417 | 10k | 41.7% | US minimum to be called gold | $59.10 |
| 585 | 14k | 58.5% | US, Northern Europe, Russia | $82.92 |
| 750 | 18k | 75% | Southern Europe, fine jewelry worldwide | $106.30 |
| 916 | 22k | 91.6% | India, Middle East, Asia | $129.83 |
Why 375 is British and not American
The UK has hallmarked precious metals since 1300, and 9 carat has been a legal standard there since 1854, introduced to make gold jewelry affordable. UK law today recognizes gold at 375, 585, 750, 916, 990 and 999, and any gold article above a small weight threshold must carry a full hallmark struck by one of four assay offices before it can be sold as gold. The result is that most gold sold on British high streets for the last century and a half is 9 carat, and it is stamped 375 with the hallmark beside it.
The US went the other way. The Federal Trade Commission's Jewelry Guides say a product of less than 10 karat may not be described as gold at all, so American jewelers do not make or stock 9k, and an American sees 375 mostly on a grandmother's ring from Manchester or a chain bought on holiday in Dublin. The piece is real gold, it is simply below the US threshold for the word; a buyer will test and pay for 37.5% gold, and a jeweler will repair it like any other alloy.
Reading the marks next to 375
A genuine British piece carries more than the number. A full UK hallmark has three compulsory parts, and older or foreign pieces add or drop marks in predictable ways.
| Mark | What it means |
|---|---|
| Sponsor's mark | initials in a shield identifying the maker or importer |
| Fineness mark | 375 in an oval for gold |
| Assay office mark | a leopard's head for London, an anchor for Birmingham, a rose for Sheffield, a castle for Edinburgh |
| Date letter | on older pieces; before 1975 gold also carried a crown |
| Harp | Irish pieces |
| 375 or 9ct alone | usual on Australian pieces, stamped by the maker without an assay mark, because Australia has no compulsory hallmarking |
A lone 375 with no other marks is common on Australian, older or lightweight items and on imports, and is also what a counterfeiter stamps, so a lone number is a claim to test, not a guarantee. The stamp decoder covers the letters that mean plated or filled, which can sit next to a 375 and change its meaning entirely: 375 GP is a 9 karat layer over base metal, worth almost nothing as scrap.
Stamp decoderWhat 417, 585, 750, GF or GP meanOpen calculatorHow 9k wears and looks
With 62.5% of the metal being copper, silver and zinc, 9 karat is the hardest of the karat golds and resists scratching and bending better than 14k or 18k, which is why British sellers call it durable. The same alloy content makes it the most reactive: it tarnishes sooner, it can darken the skin of people with acidic sweat, and it is the most vulnerable to chlorine cracking, so 9 carat rings should not go in pools. Its color is paler and often slightly redder than 14k because there is simply less gold to see; red 9 carat, heavy in copper, is a classic Victorian look, and white 9 carat needs rhodium plating to look white at all.
Solder is the weak point: 9 carat repair solder has to be a lower melting alloy still, so old repairs on 375 pieces are often the first thing to fail. A jeweler used to 14k can work it, but the joints deserve a look before buying a vintage piece.
Is 375 the same as 14k?
No, and the confusion is worth clearing up because it costs people money. 14k is 585, 58.5% gold, more than half again as much gold per gram as 375. A buyer who tests a 375 piece and pays a 14k price is being generous; a seller who sells a 375 piece as 14k is committing fraud in most jurisdictions. Where the mistake comes from: 9 carat and 14 karat are both "the everyday gold" of their countries, and both look like gold. Look at the number, not the reputation.
Testing a 375 piece
- Acid kits are graded 10k, 14k, 18k and 22k, and 9 karat reacts faintly to the 10k acid, which is the expected result, not a failure.
- Electronic testers read it as 9k or as low 10k.
- Density is the cleanest home check: 9 karat yellow gold sits around 11.2 to 11.4 grams per cubic centimeter, below 10k at about 11.5 and well below 14k at 13; the method is on the testing page.
Fake 375 stamps exist on brass and on plated pieces, so a stamp plus a British assay mark is worth more than a stamp alone, and either is worth less than a test.
Selling 375 gold
- grams
- pennyweight (dwt)
- troy ounces
Gold in your 375 piece
$531.51
10 g × 37.5% gold = 3.75 g of pure gold at $141.74 per gram. Buyers pay a share of this.
- Mail-in refiner, 85–90%
- $451.79–$478.36
- Local buyer, 50–70%
- $265.76–$372.06
- Gold per gram of this alloy
- $53.15
Spot $4,408.50/oz t = $141.74/g · gold-api.com · 2026-09-04
Scrap buyers pay on gold content, so the arithmetic is weight × 0.375 × spot per gram, then their percentage. At today's price a 10 gram 9 carat bracelet holds $531.51 of gold; a good mail-in refiner might pay 85 to 90% of that, a shop around half. Because 9 carat pieces are often older and hand finished, check the resale route first: a signed Victorian 9 carat locket sells for several times its melt value whole, and melting it is the one mistake that cannot be undone. The selling guide walks through both routes and how to check an offer.
Check an offerAny buyer's quote as a share of melt valueOpen calculatorQuestions people ask
What does 375 mean on a ring?
Nine karat gold: 375 parts gold per thousand, 37.5% by weight, the rest copper, silver and zinc. It is the standard gold of the UK, Ireland and Australia. In the US it is real gold but below the 10 karat minimum for the word, so it usually arrives as an inherited or travel piece.
Is 375 gold worth anything?
Yes, exactly 37.5% of the gold price by weight. A gram holds $53.15 of gold at today's spot, a 10 gram chain $531.51. A buyer pays a share of that. Older British 9 carat pieces with hallmarks often sell for more whole than melted, so get a resale opinion before scrapping.
Is 375 gold real gold?
It is real gold alloy at 37.5% purity, hallmarked as gold in the UK and most of the Commonwealth. The US Federal Trade Commission does not let anything under 10 karat be called gold, which is a labeling rule, not a judgment on the metal. Tested, it behaves like gold at its purity and sells for its gold content.
Is 375 gold better than 10k or 14k?
Harder and cheaper, but with less gold and more upkeep. 9 carat scratches least and tarnishes most, and it is the most vulnerable to chlorine. 14k holds more than half again as much gold and stays brighter. For everyday rings in a dry climate 9 carat is fine; for value per gram it is the lowest of the karat golds.
Does 375 gold tarnish or turn skin green?
More readily than higher karats, because 62.5% of it is reactive metal. Expect a faint dulling in storage and, on wearers with acidic sweat, a grey or green mark on the skin. Both come off with warm soapy water; the metal underneath is unchanged.
What does 375 with GP, GF or RGP mean?
That the 375 describes a gold layer, not the piece. GP is plated, GF gold filled, RGP rolled gold plate. The base metal is brass or copper, the gold content is a fraction of a percent of the weight, and scrap buyers will not pay for it. A plain 375 in an oval with an assay office mark is solid 9 carat.