Is My Gold Real? What a 14K Stamp Does and Doesn’t Prove

Short answer: a stamp such as “14K” or “585” is the maker’s or importer’s own statement of how much gold the piece contains. In the US, no assay office or government agency checks that mark before the piece is sold. Federal law requires the mark to be accurate within a small tolerance, and requires the name or trademark of whoever applied it to sit beside it, so a stamp makes real gold more likely, but it doesn’t prove it. At home, a magnet can show that a piece is not gold or silver; a piece that doesn’t react can still be brass, copper or plated metal. A definite answer comes from a jeweler’s test. Before you buy online, read the whole metal description, not just the title, and check the seller and the return policy.

If you’ve just noticed the tiny “14K” inside a ring and wondered whether to trust it, here is who puts that mark there and how far you can rely on it. For what 14K, 585, 925, GF and similar marks stand for, see our guides to solid, plated, filled and vermeil gold and to 10K, 14K and 18K gold.

Who puts the stamp there

In the US, a quality mark is applied by whoever makes or imports the piece. There is no independent assay office that tests it first, as there is for hallmarks in the UK, so the stamp is the supply chain’s own claim about its product.

The claim is regulated. The National Gold and Silver Stamping Act, as published in the United States Code (2024 edition), makes it unlawful for a manufacturer or dealer to ship a gold or silver article bearing “any mark or word indicating or designed or intended to indicate that the gold or silver or alloy of either of said metals in such article is of a greater degree of fineness than the actual fineness or quality”.

Section 297(b) adds that whoever applies a gold or silver quality mark must also apply a registered (or applied-for) trademark or “the name of such person”, “in a position as close as possible to that quality mark or stamp”. Where a piece has parts of different quality and one part carries a quality mark, each other part needs a mark of its own. In practice, a “14K” on a clasp describes the clasp.

The Federal Trade Commission’s Jewelry Guides add wording rules. 16 CFR 23.3 says: “It is unfair or deceptive to misrepresent the presence of gold or gold alloy in an industry product, or the quantity or karat fineness of gold or gold alloy contained in the product”. For silver, 16 CFR 23.5 lists “Sterling” among descriptions that may be misleading “unless it is at least 925/1,000ths pure silver.”

This article is general information, not legal advice. We quote these rules so you can see what they say, and we draw no conclusion about any seller or listing.

How close to the stamp the gold has to be

Under 15 U.S.C. 295, the actual fineness “shall not be less by more than three one-thousandth parts than the fineness indicated by the mark” when the part tested contains no solder. With the solder included, the limit for most jewelry is “seven one-thousandth parts”. In plain words, the gold in a marked piece may fall a little short of the mark, but only by a few parts in a thousand.

Why a stamp can still be wrong

NBC 7 San Diego reported in August 2026 on a buyer whose ring, bought “from a third-party vendor on Amazon”, was “advertised as 14-karat white gold and bearing a 14K stamp”. He had it tested at a jewelry store: “Turns out, no trace of gold whatsoever.” The report says the gold detector “showed 0.00 karats, and the ring was mostly copper despite its 14K stamp.” Amazon told NBC: “In this case, we removed the product and are working with the customer to make this right.”

In a 2013 Ganoksin thread, a member who sells chains at a market stall wrote: “I had a ‘sterling silver’ fineness mark 925 on a disk on a snake chain XRF’d. Silver plated brass was the result.” Another poster noted that “you can buy 925 punches on ebay and other sites”. On finishing.com in 2005, a process engineer, Mark Baker, told a reader: “Being stamped 14K does not always mean they are.”

We found no count of how often stamps are wrong, and we don’t offer one. Treat a stamp as a starting point.

What you can check at home, and what it can’t tell you

• Look for the name beside the mark. A karat or “925” mark with a name or trademark next to it is what the law describes. A bare mark tells you less.
• Read every part. A clasp, jump ring or bail can be a different metal from the chain or ring.
• Use a magnet only to rule metal out, and only for the part that reacts, since a clasp or fitting can be a different metal. Cadmore Auctions, a UK auction house, says of the magnet test: “It helps you filter out base metals, but it can’t confirm authenticity.” Its next step, checking the hallmark, relies on the UK’s independent assay system, which the US doesn’t have.
• Don’t treat skin marks as a test. As our guide to black or green marks on skin explains, “a dark grey or black smudge from a gold ring is usually not a sign that the gold is fake”.
• Don’t file, scratch or acid-test it yourself. In a 2025 Ganoksin thread, a contributor who signs as AJ described filing a hidden spot as “my least favorite since it mars the piece and voids returns.” In our view the same caution applies to any home test that marks the surface, including acid kits.

The same 2025 thread shows how hard this is to judge by eye. A parent asked whether a pendant sold as “925 sterling” was real after it “all turned yellow” when heated, and some replies suspected plating. The poster’s later follow-up said: “Behind a thin layer of mother of pearl some other kind of metal act as background and created the yellowness when heated.” It may not have been a fake at all, and looking at it couldn’t have settled the question.

Getting a definite answer

Take the piece to a jeweler. In the 2025 thread, AJ also proposed “a specific gravity test”, with “a scale accurate to 0.01 g”, and wrote that “This test can easily distinguish sterling from brass.” AJ offered it as something an owner could try; it needs the right equipment and care, so we’d leave it to someone who does it routinely. Jewelers may also test with acid on a hidden spot, or with an XRF analyser, as with the 2013 chain. Before any test, ask whether it will leave a mark, and do it inside your return window, so a poor result still leaves you options.

What do marks like 750, 585 or 916 mean on an inherited or foreign piece?

They are fineness numbers, giving the gold content in parts per thousand. The UK’s Hallmarking Act 1973 defines fineness as “the number of parts by weight of that fine metal in one thousand parts by weight of alloy”, and Schedule 2 lists the standard marks for gold as the figures 375, 585, 750, 916, 990 and 999. So 750 means 750 parts of gold in every thousand: 75 percent, or 18 karat. By the same arithmetic, 585 is about 14 karat, 375 is 9 karat, and 916 (the mark for gold of 916.6) about 22 karat; our 10K, 14K and 18K guide has the table. The FTC Jewelry Guides give their examples in karats instead, such as “14 Kt. Gold” and “9 Kt. Gold” (16 CFR 23.3).

A UK hallmark is struck by an assay office, after testing. Under section 4 of the Act, an article that “upon assay is found in all its parts to be of a standard of fineness not less than the minimum fineness” is struck with the assay office’s own mark and the standard mark. Schedule 2 gives the office marks as a leopard’s head for London, a castle for Edinburgh, an anchor for Birmingham and a rose for Sheffield. A crown or a date letter is added only if the person submitting the piece asks for it.

Those are the UK’s marks under the Act as it stands today. Other countries have their own marking rules, and an older piece may predate today’s rules, so we don’t try to identify or value any particular piece from its marks. A jeweler can test the metal, as described above, and an appraiser can estimate what it’s worth; our guide to appraisals and paperwork explains what an appraisal includes.

Red flags in an online listing

• “Gold” with no karat in front of it. Among descriptions that may be misleading, the FTC Guides list the word “Gold” used without qualification for a product “which is not composed throughout of fine (24 karat) gold.”
• Vague plating words. “Gold tone” describes a colour, and “18K plated” describes only the surface; neither tells you what metal is underneath, and a plating term alone doesn’t tell you how far the layer exceeds the FTC minimum. Our gold types guide explains the thickness rules.
• A price that seems too low for gold. BBB’s advice, reported by National Jeweler in 2023: “If a deal seems extraordinarily good, stay skeptical”.
• Photos and little else. The jeweler NBC spoke to, Arturo Carrera, recommends “carefully reading the item’s description and understanding jewelry terminology”, and the report adds that “Images can be altered, and the piece shown may not be the exact item ultimately delivered.”
• No seller identity or return policy. The same report says shoppers “should also research the seller, read reviews and understand the return policy before purchasing.”

If it isn’t what was described

Contact the seller in writing inside the return window, and keep the test result; the NBC buyer photographed his. If you bought through a marketplace, report it there too. You can also report a seller to the FTC at ReportFraud.ftc.gov or to your state attorney general. None of these routes promises an outcome, but they put your evidence on record.

How we describe metal on our own listings

IMPERVORA doesn’t test or assay pieces itself. As our gold types guide puts it, “Our karat gold listings state the karat in the title”. Some listings also show a Metal Stamp field; where one doesn’t, read the metal named in the title and the product details.

Next step

Before you buy, read the whole listing rather than the title, and ask the seller what the piece is stamped and whether a maker’s name sits beside it. If you already own a piece you’re unsure about, a jeweler’s test inside the return window is the proportionate step. For a question about the metal on one of our listings, email Concierge@impervora.com and we will tell you what the product page does and does not state.