Gold Purity Stamps Explained

Gold jewelry is stamped with a small mark showing its purity — but not every country uses karat numbers. Many use a “fineness” number instead, out of 1000 parts. Here’s how to read both systems.

Karat stamps (US, UK)

Karat stamps show parts of pure gold out of 24: 24k, 22k, 18k, 14k, 10k, 9k. See the full Gold Karat & Purity Guide for the exact percentage and common uses of each.

Fineness stamps (Europe, Asia, and international pieces)

Fineness stamps show purity out of 1000, and are common on jewelry made or sold outside the US:

• 999 — 24k equivalent, 99.9% pure gold
• 916 — 22k equivalent, 91.6% pure gold
• 750 — 18k equivalent, 75% pure gold
• 585 — 14k equivalent, 58.5% pure gold
• 417 — 10k equivalent, 41.7% pure gold

The two systems describe the same purity levels, just with different labels — a 750 stamp and an 18k stamp mean essentially the same thing.

Other marks you might see

• GF (Gold Filled) — a thick layer of gold bonded to a base metal core, with meaningfully more gold than plating, but not solid gold
• GP (Gold Plated) — a thin gold layer over base metal, with very little actual gold content
• A maker’s mark or hallmark — identifies the manufacturer or assay office, separate from the purity stamp

GF and GP items have little to no meaningful melt value — the Gold Calculator is designed for solid gold items, not plated ones.