Gold Karat Stamps Explained: What 585, 750, and 916 Actually Mean in 2026
The smallest mark on a gold piece is usually the most honest one. A three-digit number stamped inside a ring shank, on a chain clasp, or near the edge of a bar tells you the purity, and purity is what sets the payout. Sellers who learn to read these stamps walk into a buyer already knowing the math, which is the single fastest way to stop leaving money on the table in 2026.
Every legitimate gold piece carries a purity mark. In the US, the older system uses karats: 10K, 14K, 18K, 22K, 24K. The rest of the world, and most modern jewelry sold in the US since the 1980s, uses the millesimal fineness system, which is just the purity expressed as parts per thousand. A 14K ring is 58.5% gold, so it gets stamped 585. An 18K ring is 75% gold, stamped 750. A 22K chain is 91.6% gold, stamped 916. The number on the stamp is the percentage of gold by weight, with the decimal removed.
The full conversion table is short and worth memorizing. 10K equals 417. 14K equals 585. 18K equals 750. 21K equals 875. 22K equals 916. 24K equals 999 or 9999 on high-purity bullion. Anything stamped below 417 is not legally gold in the US and most other markets, though you will occasionally see 333 (8K) on older European pieces. If a piece is stamped 800 or 925, that is not gold at all; 925 is sterling silver, and 800 is a lower-grade silver alloy.
The stamp location matters because counterfeit pieces often get the stamp wrong or put it in the wrong place. On rings, the purity mark sits inside the band, usually paired with a maker's mark or country-of-origin code. On chains, it is on the clasp or the small tag soldered near the clasp. On bracelets, same convention as chains. On bullion bars, the fineness is printed prominently on the face along with the refinery name, weight, and serial number. On coins, purity is not always stamped because the spec is defined by the issuing mint, but modern bullion coins like the American Eagle, Maple Leaf, and Krugerrand all carry a fineness mark somewhere on the face or edge.
What the stamp does not tell you, and where sellers get burned
The stamp tells you purity, not weight, and payout is purity times weight times the live spot price, minus the buyer's margin. A 14K chain that weighs 8 grams and a 14K chain that weighs 40 grams have the same stamp and very different payouts. Before walking into a buyer, weigh the piece on a scale that reads to 0.1 grams, write down the weight and the stamp, and do the math yourself. Take 14K (585) at 8 grams: 8 grams times 0.585 equals 4.68 grams of pure gold content. Multiply that by the current spot price per gram and you have the gross melt value. A fair buyer pays 85 to 95 percent of that for scrap; a sharp buyer pays 60 to 75 and counts on you not knowing the difference.
Plated and filled pieces are where stamps get tricky. A stamp that reads 14K GP means gold plated, which is a thin electroplated layer over a base metal core. 14K GF means gold filled, which is a thicker mechanically bonded layer, usually 1/20 or 5% by weight. 14K HGE is heavy gold electroplate, still plated. None of these are solid gold and none of these will get a solid-gold payout. A buyer who quotes you a solid-gold price on a GP piece is either confused or testing whether you are. The stamp is your defense: if it says GP, GF, HGE, or RGP (rolled gold plate), you are not selling solid gold and you should price accordingly, which usually means almost nothing for plated and a small recovery payout for filled.
Old stamps, foreign stamps, and the unstamped pieces
European gold often carries a control mark instead of a fineness number, especially pieces made before 1980. The French eagle's head is 750 (18K), the French owl is imported 18K, the British crown plus a number indicates the assay office and karat, and Italian pieces from the same era frequently carry a star and a number that maps to the manufacturer registry. Older Russian and Soviet pieces use a 583 stamp, which is a non-standard 14K used in that market until 1994. Middle Eastern pieces are typically 21K or 22K and stamped 875 or 916 respectively, often with Arabic script alongside. A buyer who specializes in gold sees all of these regularly; a pawn shop generalist may not, and may underpay on the assumption that an unfamiliar stamp is suspicious.
Unstamped pieces are not automatically fake. Plenty of legitimate antique jewelry was never stamped because the assay system did not require it at the time of manufacture. Unstamped does mean the buyer has to test the piece, usually with an acid scratch test or, for higher-value pieces, an XRF analyzer that reads the elemental composition without damaging the metal. Ask which test the buyer is using before they touch the piece. Acid scratch tests leave a small mark on a test stone and a tiny amount of metal removed from an inconspicuous area; XRF leaves no mark at all and is more accurate. A buyer with no testing equipment quoting on an unstamped piece is guessing, and a guess almost always favors the buyer.
The practical workflow is simple. Find the stamp with a loupe or a phone camera zoom. Write down the number. Weigh the piece. Multiply weight by purity to get pure-gold grams. Look up the current spot price per gram. Multiply to get gross value. Expect a fair offer between 85 and 95 percent of gross for clean scrap, lower for damaged or mixed pieces, higher for bullion bars and coins that can be resold without melting. Walk in with those numbers written down, and the conversation becomes a price negotiation instead of a guessing game.