A jewelry hallmark is a small stamp, usually inside a ring shank, on the back of a pendant or on the clasp tag of a chain, that tells you three things: the purity of the metal, who made the piece, and sometimes where and when it was tested. The purity mark is the one that matters most for value. A number like 585, 750 or 925 gives the parts per thousand of gold or silver; a karat mark like 14K or 18K says the same thing another way. Marks like GF, RGP, HGE, GP or 1/20 12K mean the piece is layered or plated, with only a thin skin of gold, and its metal value is a few dollars. With gold at about $4,000 an ounce and silver at about $40 an ounce as of late 2026, reading the mark correctly is the difference between a $5 chain and a $500 one.
Quick answer
- 375, 585, 750 and 916 mean 9K, 14K, 18K and 22K gold. 925 means sterling silver. 950 with PT or PLAT means platinum.
- GF, RGP, HGE, GP, GEP, "1/20 12K" and "plaqué" mean gold-filled or plated. The gold is worth almost nothing.
- A mark is a claim, not proof. Fakes with 750 and 925 stamps exist, so weigh the piece and test it when the number matters.
How to read a hallmark, step by step
- Find every mark. Look inside the ring shank, on the back of a pendant or brooch, on the tongue or tag of a clasp, on the back of earring posts and on the end links of a chain. Use a 10x loupe and a single bright light at a low angle, so the stamp casts a shadow. Marks on chains are tiny and often sit on a small flat tag at the clasp.
- Read the purity number or karat first. It will be a three digit number, a karat mark or a word. Match it against the tables below. If there is no purity mark at all, the piece is more often plated or costume than fine, though unmarked gold exists, especially in older, handmade and non-Western jewelry.
- Look for the letters that cancel the number. "14K GF", "1/20 12K", "RGP", "HGE", "GP", "GEP", "gold filled", "rolled gold", "plaqué or" and "vermeil" all mean a base metal or silver core with gold on the outside. Read the whole stamp, not just the K. Our guide on gold-filled vs gold-plated explains what each layer is worth.
- Find the maker's mark. A set of initials in a shaped outline, a symbol or a full name next to the purity mark tells you who made or sold it. Famous names add real value: Tiffany & Co., Cartier, Van Cleef & Arpels, Bulgari, Georg Jensen and David Yurman, among others.
- Look for assay and country marks. British pieces carry a sponsor's mark, a standard mark, an assay office symbol and a date letter. French gold carries an eagle's head; French silver a Minerva head. Italian pieces often show a star, a number and a province code like "1 AR" for Arezzo. These confirm the purity was checked by an outside office.
- Weigh it and do the math. Put the piece on a kitchen or jewelry scale. Multiply the weight in grams by the purity and by the price per gram of pure metal, then subtract stones and anything that is not metal. Dealers pay a percentage of that melt figure.
- Test if the number matters. For anything heavier than a few grams, or marked 750 or higher, a jeweler's acid test or an XRF reading takes a minute and settles whether the mark tells the truth. Our guides to how to tell if gold is real and how to tell if silver is real cover the home checks that come first.
Purity marks and what the metal is worth
Melt value uses gold at about $4,000 per troy ounce and silver at about $40 per troy ounce, as of late 2026. A troy ounce is 31.1 grams. Dealers typically pay about 70 to 90 percent of melt for scrap gold and about 50 to 80 percent for scrap silver, less for small lots.
| Mark | Meaning | Pure metal content | Approximate metal value per gram |
|---|---|---|---|
| 999, 24K, 24KT | Pure gold | 99.9 percent | About $128 |
| 916, 22K, 22ct | 22 karat gold, common in Indian and Middle Eastern jewelry | 91.6 percent | About $118 |
| 750, 18K, 18ct | 18 karat gold | 75 percent | About $96 |
| 585, 14K, 14ct, 583 (older Soviet) | 14 karat gold | 58.5 percent | About $75 |
| 417, 10K, 10ct | 10 karat gold, the US legal minimum for "gold" | 41.7 percent | About $53 |
| 375, 9K, 9ct | 9 karat gold, common in the UK and Australia | 37.5 percent | About $48 |
| 333, 8K | 8 karat gold, Germany and Scandinavia | 33.3 percent | About $43 |
| 999, Fine silver | Pure silver | 99.9 percent | About $1.29 |
| 925, Sterling, Ster | Sterling silver | 92.5 percent | About $1.19 |
| 900, Coin silver | Coin silver, common in American pieces before 1900 | 90 percent | About $1.16 |
| 835, 830, 800 | Continental European silver standards | 80 to 83.5 percent | About $1.03-1.08 |
| 950, PT950, PLAT | Platinum | 95 percent | About $45-60, depending on the day |
| 900 PT, PT900, IRIDPLAT | Platinum, older American standard | 90 percent | About $43-57 |
| PD950, Pd | Palladium | 95 percent | About $30-45, volatile |
The 10k vs 14k vs 18k gold guide goes deeper on how the alloys wear and why a heavier 10K piece can be worth more than a lighter 18K one. The guide to what 925 means on jewelry covers the sterling side and the gold-over-silver pieces that confuse people.
Marks that mean plated, filled or something else
| Mark | What it means | What it is worth |
|---|---|---|
| GF, 1/20 12K GF, 1/10 14K GF | Gold-filled: a bonded gold layer at least 5 percent of weight | About $1-5 per piece for the gold, more for good vintage makers |
| RGP, 1/40 12K RGP, Rolled gold | Rolled gold plate: a thinner bonded layer than GF | A few dollars |
| HGE, GE, GEP, GP, Gold plated | Electroplated gold, a microscopically thin skin | Essentially nothing in metal |
| Vermeil, 925 with a gold tone | Sterling silver with a gold plating | Sterling value only, about $1.19 per gram |
| Plaqué or, Doublé, Walzgold | French and German terms for rolled gold or plating | A few dollars |
| 14KP | 14 karat plumb, meaning exactly 14K, not plated | Full 14K value |
| 18K HGE | Heavy gold electroplate with the karat of the plating | Nothing in metal |
| 925 on a piece that is light and yellow | Often vermeil, sometimes a fake sterling stamp | Test before trusting |
| Silver, Sterling-look words like "Silvertone", "Nickel silver", "German silver", "Alpaca" | No silver at all; copper-nickel-zinc alloy | Costume value only |
| EPNS, EP, A1, Silver plate | Electroplated nickel silver | Costume value only |
A piece can carry a karat mark and still be plated, because "18K" on an HGE piece refers to the plating alloy.
British, European and other country marks
British hallmarking is the most systematic. Since 1300, precious metal sold in Britain has been tested by an assay office, and a full set of marks reads like a sentence: the sponsor's mark (the maker or importer's initials in a shield), the standard mark (a lion passant for sterling, a crown with a karat number for gold before 1999, now just the number such as 750), the assay office mark (a leopard's head for London, an anchor for Birmingham, a rose for Sheffield, a castle for Edinburgh) and a date letter in a particular shield and font that pins the year. A piece with all four, read against a published date letter chart, can be dated to the year. Imported pieces carry an additional mark. Very light pieces are exempt and may be unmarked.
France uses an eagle's head for 18K gold, an owl for imported gold and a Minerva head for silver, with a boar's head for small silver items. Italy stamps a star, a registration number and a two letter province code, plus the purity such as 750. Germany uses a crescent moon and crown with the purity number for silver. Russia and the Soviet Union used a star with a hammer and sickle and a purity like 583 or 875. Mexico stamps an eagle with a number for mid-century silver, later replaced by a letter and number code such as TM-27, with a 925 mark. Scandinavian pieces often carry 830S or 925S with the maker's name. American jewelry from before the 1906 stamping act is often unmarked, which is why so much Victorian American gold needs a test rather than a reading.
Dating a piece from its marks
Marks shift over time, which helps with dating. "14K" alone is American and usually after 1906. The "KP" plumb mark appeared after 1978. British gold with a crown and "18" is before 1999. "Sterling" in full is American or Canadian; "925" alone became common worldwide after about 1970. "900 PT" or "IRIDPLAT" is usually American, about 1900 to 1950. Our guide to how to tell if a ring is antique uses the same clues alongside construction and wear.
What a photo can show
A sharp macro photo of the mark, lit from the side, usually settles the purity and the maker. It also shows whether the stamp looks struck or cast, since fake marks on cast pieces are often soft and blurry, and whether the color of the metal is consistent at the worn high points, since plated pieces wear through to a different color at edges and clasps. A photo cannot weigh the piece or test it, so for anything heavier than a few grams the scale and the acid test come next.
How WorthPic reads hallmark photos
WorthPic runs on the newest and most capable AI model available, tuned for exactly this kind of identification. With a hallmark, the job is reading a few millimeters of stamped metal, and the model does that the way a dealer does: it reads the purity number or karat, picks out the letters that turn it into plated or filled, matches the maker's mark and any assay symbols, and checks whether the color, wear and construction of the piece agree with the mark. It gives an honest value range built on the metal content and the maker, says what would change the number, and tells you plainly when the stamp is not legible in the photo and which shot would fix it, usually a macro from a lower angle with a lamp to one side. It identifies and estimates; it cannot weigh or test the piece. For a stamped piece that is heavy, marked 750 or above, or carries a famous name, a jeweler with a testing kit and the maker's own records are what settle it.
Common mistakes
- Reading "14K" and stopping. The GF, HGE or RGP that follows changes the value from hundreds of dollars to a few.
- Trusting a stamp on a very light, very yellow piece. A 585 stamp costs nothing to apply, and bright, light, thin chains with crisp stamps are a common fake.
- Confusing "925" with "925 vermeil" on a gold-colored piece. The gold is plating; the value is sterling.
- Treating "German silver", "nickel silver" or "Alpaca" as silver. They contain none.
- Assuming unmarked means fake. Much antique, handmade, Asian and Middle Eastern gold is unmarked and tests fine.
- Missing a maker's mark that matters. A small "T&Co" or a Georg Jensen stamp can be worth more than the metal.
- Ignoring the weight. Two rings with the same 18K stamp can differ by ten times in value simply because one is hollow.
What to photograph
- A macro of each mark, lit from one side at a low angle so the stamp casts a shadow.
- The whole piece on a plain background with a coin for scale.
- Worn edges, the clasp and the back of the piece, where plating wears through first.
- The scale readout with the piece on it, in grams.
- Any stones face on, so they can be separated from the metal estimate.
- Any signature, box or receipt that came with the piece.
When to get it looked at in person
- A jeweler with a testing kit can acid test or run an XRF reading in a few minutes, often at no charge for a customer, and can tell you the weight and the melt value on the spot. The right route for anything stamped 585 or higher that weighs more than a few grams.
- A precious metal buyer or refiner pays closest to melt value on scrap. Get two quotes; the spread between buyers is wide.
- A specialist dealer or auction house is the route for signed pieces from Tiffany, Cartier, Van Cleef & Arpels, Bulgari, Georg Jensen and similar makers, where the name is worth more than the metal.
- An appraiser charges about $50-150 per piece or $100-300 an hour and is the route for insurance, estates and pieces with significant stones.