What the stamps inside your gold jewelry mean
Most of the code is easy to read. Some of it is built to be misread. None of it is proof. Here is the whole alphabet, from 585 to KP.
The number is a purity code
The three digit number stamped inside gold jewelry is its purity, written in parts per thousand. A ring marked 585 is 585 parts gold out of 1,000, which is the same metal an American maker would stamp 14K. The number and the karat are two spellings of one fact.
| Stamp | Karat | How much gold |
|---|---|---|
| 999 | 24k | 99.9%, effectively pure |
| 916 | 22k | 91.6% |
| 750 | 18k | 75% |
| 585 | 14k | 58.5% |
| 417 | 10k | 41.7% |
| 375 | 9k | 37.5%, common on British pieces |
American jewelry usually carries the karat mark and European jewelry the number, so one family drawer can hold a 14K ring and a 585 chain made of identical gold. Which karat belongs on your hand is a different question. This site keeps a whole guide on 14k against 18k for exactly that.
The letters after the number change the meaning
Read past the number, because the letters after it say whether the gold goes all the way through. A hopeful eye sees 18K and stops. The stamp 18K GP describes a different object that photographs the same.
- GP, GE and HGE mean plated. A thin wash of real gold over another metal. The stamp is honest about it, in letters most people never read.
- GF means gold filled, a thicker bonded layer. It usually comes with a fraction, so 1/20 14K GF says the gold layer is one twentieth of the weight of the piece.
- 925 is not a gold mark at all. It is sterling silver. On a gold colored piece it means vermeil, a silver body under a gold surface.
- KP is the surprise. 14KP does not mean plated. The P stands for plumb, an old assurance that the piece is exactly 14 karat rather than rounding up.
One more mark worth knowing sits next to the number rather than after it. American made pieces are supposed to carry the maker's trademark beside the purity stamp. A lone 585 with nothing next to it is not evidence of a fake. It is a reason to look closer.
Why a stamp is not proof
A stamp is pressed into the metal by whoever made the piece. A counterfeiter owns the same punches. Brass stamped 750 exists. So does plated jewelry whose honest suffix has worn away, leaving a bare 18K where 18K GP used to be. The mark tells you what the piece claims to be. It cannot tell you what the piece is.
It cuts the other way too. Real gold goes unstamped all the time. Rings lose their mark when they are resized, because the stamped section of the band is often the piece the jeweler removes. Older jewelry and handmade jewelry frequently never had a mark. A bare band does not make a piece fake. It makes it an open question.
Age adds its own noise. Marks wear soft on a ring that has been worn for forty years. A worn 585 reads a lot like a worn 555, which was never a standard at all. When the stamp is doubtful, the stamp stops mattering. The metal has to speak for itself.
Where the stamps hide
On a ring, look inside the band. On a chain or bracelet, look at the clasp and the small flat tag beside it. Earrings carry their mark on the post. A pendant is usually stamped on the bail, the little loop the chain runs through.
The marks are small on purpose, so do not squint at them. Take a photo with your phone and zoom in. A picture you can enlarge beats a loupe you do not own. It also gives you something to show a jeweler without handing over the piece.
What settles it
A test settles it. The stamp tells you where to start and the test tells you what you are holding. Astra Jewelers in Montclair weighs and tests gold in front of you on a certified scale, then explains what the reading means before anything else is discussed. There is no charge for finding out and no obligation once you know.
So bring the piece with the strange mark or the worn mark or no mark at all. The stamps are a good first read of a drawer of inherited gold. This guide should help you sort the 750 from the 18K GP at the kitchen table. The metal answers the rest.
Common questions
What does 925 mean on gold jewelry?
The piece is sterling silver, not solid gold. 925 means 92.5% silver. On jewelry that looks gold it indicates vermeil, a layer of gold over a silver body. Vermeil is real jewelry with a real silver value, but its gold content is only the surface.
What do 417, 585, 750 and 916 mean?
They are purity in parts per thousand. 417 is 10 karat, 585 is 14 karat, 750 is 18 karat and 916 is 22 karat. The European number and the American karat mark describe the same metal two ways.
Does 14KP mean my ring is plated?
No, the opposite. The P stands for plumb, an assurance that the piece is exactly 14 karat rather than rounded up from something less. Plated marks are GP, GE and HGE. Gold filled is GF.
What is the difference between gold filled and gold plated?
Thickness, mostly. Plating is a thin electroplated wash of gold over another metal. Gold filled is a much thicker layer bonded to the base, usually at least one twentieth of the piece's weight, which is what a stamp like 1/20 14K GF is declaring. Neither is solid gold.
Is gold with no stamp fake?
Not necessarily. Rings lose their stamp in resizing, older and handmade pieces often never carried one and marks wear away with decades of use. An unstamped piece is unproven rather than fake. A quick test in person settles which it is.
How do I find out what my gold is actually worth?
Have it weighed and tested in person. The stamps narrow things down but only a test confirms purity. Weight does the other half of the arithmetic. Astra Jewelers in Montclair does both in front of you on a certified scale and explains the result. Honest numbers need the piece present, which is why nobody serious quotes gold over the phone.