How to Read Jewelry Hallmarks and Maker’s Marks

Short answer: Jewelry hallmarks and purity stamps tell you what a piece is made of, who made it, and sometimes where and when. Gold is marked in karats or parts per thousand (14K or 585, 18K or 750), sterling silver is marked 925 or STERLING, and platinum PLAT, PT, or 950. Codes like GF, GP, HGE, RGP, and EPNS mean the piece is filled or plated. Any stamp can be wrong, so confirm anything valuable with a test.

Turn the ring over and there’s a stamp about the size of a grain of rice. 585? GF? A tiny crown? A number followed by “AR”? It looks like nonsense until you know that those marks are answering four different questions.

What are the different kinds of jewelry marks?

There are four kinds of jewelry marks: purity marks, plating and filled codes, maker’s marks, and country or date clues. Each kind of stamp answers a different question, and most confusion comes from reading one as if it were another. Purity marks say what the metal is (14K, 925), while plating and filled codes say what it isn’t (GP, GF, EPNS). Maker’s marks say who made it, whether that’s a name, initials, or a logo. Then there are the country and date clues, which tell you where and roughly when (“Occupied Japan,” a copyright symbol, a British assay mark).

A single piece can carry one of each, or just one, or nothing at all (which is less alarming than it sounds, as you’ll see below).

Where are the marks on jewelry?

Marks hide in predictable places, usually inside, on the back, or on the clasp. On a ring, check the inside of the band. On a chain, look at the clasp and the little tag next to it. On a brooch, check the back, near the pin stem. On a pendant, look at the back and the bail. For earrings, try the post, the back, and the closure. Bracelets are usually marked on the clasp, the hinge, or a small tag.

A jeweler’s loupe is cheap and worth having. No loupe? Use your phone camera and zoom in, in bright light. Marks wear down, so a partial stamp is normal. A blurry photo of the right spot is more useful than a sharp photo of the wrong one.

What do the numbers on gold, silver, and platinum jewelry mean?

The numbers are purity marks: they say how much of the precious metal is in the piece. Gold is marked in karats or in parts per thousand.

• 10K or 417
• 14K or 585
• 18K or 750
• 22K or 916
• 24K or 999 (pure, and soft)
• 9K or 375 is common on British and European pieces

Silver is usually 925, STERLING, or STER. You’ll also see 800 and 835 on European pieces (lower purity) and 900 on older American coin silver. Platinum is typically PLAT, PT, or 950.

For the tests that back these stamps up, see our guides to telling if gold is real and if jewelry is sterling silver.

What do GF, GP, HGE, and RGP mean on jewelry?

GF, GP, HGE, and RGP all mean the piece is not solid gold. These are the marks that tell you a piece is not solid, and they matter as much as the purity marks. GF or gold filled is a real, thick layer of gold bonded over a base metal. A mark like 1/20 12K GF means the gold is one-twentieth of the piece’s weight and 12 karat. GP (gold plated), GEP, HGE (heavy gold electroplate), and RGP (rolled gold plate) are all plating, and plating can wear through. Vermeil is gold over sterling silver.

On silver, EPNS (electroplated nickel silver) and silver plate mean silver plated over a base metal. And nickel silver or German silver contains no silver at all, despite the name. Our gold filled vs plated vs solid guide goes into what each is worth.

One more you’ll see on stone-set pieces: CTW (or TW) means carat total weight, the combined weight of the stones (usually diamonds).

What is a maker’s mark on jewelry?

A maker’s mark identifies who made the piece. It can be a full name, initials, a logo, or a small symbol. In the US, a quality stamp is supposed to come with the maker’s registered trademark, which is why you’ll often see a name or logo right next to the 14K or sterling stamp. Signed costume jewelry (think Trifari, Coro, or Napier) usually carries the name, sometimes with a copyright symbol or patent note. Not every maker signed, though: Miriam Haskell pieces were rarely marked before about 1950. Our guide to vintage costume jewelry marks covers the major makers’ signatures and how to date them.

Handmade pieces are different. Independent makers often stamp their initials or a small personal symbol, or nothing at all. Initials alone are hard to trace, since the same two letters can belong to plenty of different makers, so the seller is the best source, and a good listing will say who made it.

How do you find out who made a piece from its mark?

You find the maker by searching the exact mark and comparing sold pieces. Photograph the mark up close. Search the exact letters, or describe the symbol in words, plus “jewelry mark.” For US company names, the USPTO trademark search can show who registered a name and when. Then look at sold listings for the same mark. If the pieces that come up look like yours, you probably have the right maker.

Can a jewelry mark tell you when a piece was made?

Sometimes. Country names and a few other words and symbols can date a piece, especially costume jewelry.

• “Occupied Japan” means made under the Allied occupation, roughly 1947 to 1952.
• “West Germany” means made between about 1949 and 1990. Plain “Germany” doesn’t narrow it down.
• “Czechoslovakia” means made while that country existed, from 1918 to 1992.
• A copyright symbol on costume jewelry generally means the mid-1950s or later.
• “Pat. Pend.” means a patent application had been filed. A patent number means one was granted, and you can look that number up in the USPTO patent database to date the design.

How do you read British hallmarks?

You read a British hallmark one symbol at a time. A full British hallmark is a set of tiny pictures, each answering one question: the sponsor’s (maker’s) mark, a standard mark for the metal, an assay office mark, and often a date letter. A walking lion (the lion passant) means sterling silver in England. The assay office mark tells you where it was tested: a leopard’s head is London, an anchor is Birmingham, a castle is Edinburgh, and a rose is Sheffield (which used a crown before 1975).

What does a number and two letters mean on Italian jewelry?

A number and two letters on Italian jewelry is a manufacturer’s mark, sometimes shown with a star. The number identifies the manufacturer and the letters are the province, so AR is Arezzo (a big center for gold and silver), VI is Vicenza, AL is Alessandria, FI is Florence, and MI is Milan. That tells you who made it and where, not how pure the metal is, so look for a separate purity stamp like 925 or 750 nearby.

Does a hallmark prove jewelry is real?

No. Stamps can be wrong, and they can mislead in a sneakier way: a clasp can be marked 14K while the chain it holds isn’t solid, and a listing that says “14K” may only be describing the clasp. Treat a mark as a strong clue, then confirm it with a test, especially for anything expensive.

Does jewelry without a hallmark mean it’s fake?

No, a missing hallmark isn’t automatically a problem. American pieces from before the 1906 Stamping Act often have no quality mark, and so do very small pieces, heavily worn ones, and plenty of handmade work. If you’re buying, ask the seller how they know what it’s made of. If you’re selling, say “unmarked” plainly, say whether you’ve tested it, and don’t promise a metal you can’t back up.

Photograph the marks

If you’re selling, a close-up of every stamp is the cheapest way to earn a buyer’s trust, and it’s the first thing an experienced buyer looks for. Our jewelry photography guide shows how. If you’re buying, ask for the photo. It’s a normal request, and a seller who has the stamp can send it in a minute.

Once you can read the marks, you can usually tell what a piece is made of, and often who made it and roughly when. It’s a bit like learning a new alphabet (a very small one, printed very small). And if you find a mark that stumps you, send it our way.

Sources

• FTC Jewelry Guides, 16 CFR Part 23
• National Gold and Silver Stamping Act, 15 U.S.C. chapter 8
• The Goldsmiths’ Company Assay Office: hallmarking guide (PDF)
• NIST: precious metals fineness and conversion information (PDF)