Gold Hallmarks Explained: What the Stamps on Your Jewelry Actually Mean

The tiny stamp inside a ring band or on a necklace clasp is a precise statement about what that piece is made of. Reading it takes ten seconds and gives you more information than most sellers arrive with.

Gold hallmarks are not decorative. They are a standardized system — required by law in the United States on any item sold as gold — that communicates the purity of the metal alloy. Understanding the system means you can verify a buyer's evaluation rather than accepting it on faith.

U.S. karat stamps: what the numbers mean

American jewelry uses karat (K) designations. The number indicates how many parts out of 24 are pure gold:

• 24K — 99.9% pure gold. Rarely used for jewelry because it is too soft. Common in coins, bars, and investment-grade bullion.
• 22K — 91.7% gold. Used in some high-end pieces and certain sovereign bullion coins (American Gold Eagle, Krugerrand).
• 18K — 75% gold. Common in fine jewelry, designer pieces, and European imports. Higher purity means higher melt value per gram.
• 14K — 58.5% gold. The most common karat in American jewelry made after 1940. Good balance of durability and gold content.
• 10K — 41.7% gold. The minimum legal standard in the U.S. for an item to be sold as gold. Common in class rings, fashion chains, and lower-price-point jewelry.

European millesimal fineness marks

European and some Asian jewelry uses a three-digit number expressing gold content in parts per thousand:

• 999 — 24K equivalent (99.9% gold)
• 750 — 18K equivalent (75% gold)
• 585 — 14K equivalent (58.5% gold)
• 417 — 10K equivalent (41.7% gold)

A piece stamped 585 from an Italian manufacturer and one stamped 14K from an American manufacturer contain the same gold content. They pay the same per gram at any reputable buyer.

Marks that do not mean solid gold

Some marks look like gold hallmarks but indicate a non-solid gold item:

• GF or Gold Filled (sometimes written as 1/20 14K GF) — A layer of gold mechanically bonded to a base metal core. The gold layer is thicker than plating but the piece is not solid gold. Melt value is essentially zero.
• GP, GEP, HGE — Gold plated, gold electroplated, heavy gold electroplate. A very thin gold coating over base metal. No melt value.
• RGP — Rolled gold plate. Similar to gold filled but with a thinner gold layer. No melt value.
• 925 — Sterling silver. Not gold. A common point of confusion because sterling often uses a similar stamp style to gold millesimal marks.

When there is no stamp

Older American pieces (pre-1906), some handmade items, and certain imports may carry no hallmark. The absence of a stamp does not prove the piece has no gold content. It means the piece requires testing before any offer can be made.

At BuyGoldHub, every piece is tested with XRF spectrometry regardless of stamps. The instrument reads actual elemental composition and returns a precise karat equivalent. A stamp confirms what the alloy should be; the XRF confirms what it actually is. Occasionally an older piece tests higher than its stamp, and occasionally an import tests lower. The XRF reading is what determines the payout.

For the payout math once you know the karat, see our gold karat payout explainer. To get a live estimate before you come in, use our gold calculator.