Jewelry Hallmarks Guide: What Every Gold & Silver Stamp Means (2026)

Quick Answer

Jewelry hallmarks are small stamped marks that certify a metal's purity. Gold hallmarks include 750 (18K, 75% gold), 585 (14K, 58.3% gold), and 417 (10K). Silver uses 925 (sterling, 92.5% silver). Plated pieces show GP, HGE, or GF — not solid gold.

TL;DR

750 = 18K gold | 585 = 14K gold | 417 = 10K gold | 375 = 9K gold
925 = sterling silver | 925 Italy = Italian sterling silver
GP, HGE, GF = gold plated/filled — not solid gold
Find the stamp inside rings, near clasps on necklaces, or on earring posts
No hallmark at all = ask for a certificate or test the metal before buying

You're looking at a piece of jewelry and notice a tiny stamped number or abbreviation. What does it mean? Is this real gold? Is it sterling silver? Is it plated? Those tiny marks — called hallmarks — tell you everything you need to know about what the metal actually is. This guide covers every hallmark you'll encounter on gold, silver, and plated jewelry, with a complete reference table for each metal type.

What Are Jewelry Hallmarks?

A jewelry hallmark is an official stamp applied to precious metal items to certify their metal content. The practice dates to 14th-century England, when goldsmiths in London were required to bring their work to Goldsmiths' Hall for assay and marking — hence "hallmark." Today, hallmarking systems vary by country but serve the same purpose: protecting buyers from misrepresented metal quality.

According to the Jewelers of America, the US Federal Trade Commission requires jewelry sold as gold to be accurately described by karat, and pieces stamped with a karat quality mark must be within a half-karat of the stated quality.

Two hallmarking systems exist side by side globally:

Karat system (US, UK, Middle East): expresses gold purity as parts out of 24 — 18K = 18/24, 14K = 14/24
Millesimal fineness (Europe): expresses purity as parts per 1,000 — 750 = 750/1,000 = 75%, 585 = 58.5%

Both systems coexist on the same SERPs because jewelry moves across markets. A European piece says 750 where an American piece says 18K — same gold, different notation.

Gold Hallmarks — Complete Reference Table

Every gold hallmark corresponds to a specific karat and purity percentage. This table covers all gold hallmarks you're likely to encounter:

Karat	European Mark	Gold %	Also Stamped As	Common Use
24K	999	99.9%	999.9, 24KT	Gold bullion, coins — too soft for most jewelry
22K	916	91.6%	916.7, 22KT	Traditional Indian/Middle Eastern ceremonial jewelry
18K	750	75%	18KT, 18CT, 18K P	Fine jewelry, luxury brands, hypoallergenic preference
14K	585	58.3%	14KT, 14CT, 14K P	Most popular in US — everyday rings, engagement rings
10K	417	41.7%	10KT, 417 mark	Budget gold jewelry — minimum legal karat in the US
9K	375	37.5%	9CT, 9KT, 375 mark	Common in UK, Ireland, Australia — not legal as gold in US

Key rule: In the US, any piece must be at least 10K (41.7% gold) to be sold as gold jewelry. In the UK and Australia, 9K (37.5%) is the legal minimum. A piece stamped 375 is legal fine gold in London but technically can't be called gold jewelry in New York.

Silver Hallmarks — Complete Reference

Silver jewelry uses a different scale — fineness expressed as parts per 1,000 (the millesimal fineness system):

Hallmark	Silver %	Name	Notes
999	99.9%	Fine silver	Too soft for most jewelry — used for coins, bullion
925	92.5%	Sterling silver	The global standard for silver jewelry — most common mark you'll see
925 Italy	92.5%	Italian sterling silver	Same purity as 925 — made in Italy; also seen as "925 ITA"
800	80%	Continental silver	Common in older European pieces — lower quality than sterling

Gold Plated, Filled & Electroplate Marks

These marks tell you the piece is NOT solid gold — it has a gold coating over a base metal:

Stamp	Full Name	Gold Layer	Lifespan
GP	Gold Plated	Under 0.5 micron	6–12 months daily wear
GEP	Gold Electroplate	Min. 0.175 micron	1–2 years daily wear
HGE	Heavy Gold Electroplate	Min. 2.5 microns	2–5 years daily wear
GF	Gold Filled	5% of piece weight, bonded	10–30 years with care
RGP	Rolled Gold Plate	Mechanically bonded	5–20 years

A stamp like 18K GP means the gold layer is 18K purity, but the piece is plated — not solid 18K gold. The 18K refers only to the quality of the plating layer.

Jewelry hallmark stamps close-up — 925, 750, 585, 14K

How to Read a Jewelry Hallmark

Follow these four steps:

Find the stamp. Look inside the ring band, near the clasp on necklaces and bracelets, or on the post of earrings. You may need a jeweler's loupe (10× magnification) for small pieces.
Identify the mark type. Is it a number (925, 750, 585)? A karat stamp (18K, 14K)? An abbreviation (GP, HGE, GF)? Or a maker's mark (initials in a shield or oval)?
Cross-reference the table. Numbers = fineness (use the tables above). Karat stamps = direct purity. Abbreviations = plated/filled.
Check for additional marks. Many pieces carry multiple stamps — a fineness mark AND a maker's mark AND a country of origin. The fineness mark is what tells you metal quality.

If you can't find any stamp at all on a piece sold as gold or silver, that's a concern. In the US and UK, sellers are legally required to accurately represent metal content. A legitimate jeweler will always provide documentation or testing if asked.

How to Tell If Jewelry Is Real Gold

Use this decision tree:

✅ Stamped 10K, 14K, 18K, 22K, 24K (or their European equivalents 417, 585, 750, 916, 999) → Real solid gold
✅ Stamped 18K GP or 18K GF → Gold plated/filled — real gold coating, not solid gold
⚠️ Stamped HGE, GEP, GP alone → Plated — gold surface layer only
⚠️ No stamp at all → Unverified — request documentation or professional acid test
❌ Turns skin green → Copper-heavy base metal, very thin or no plating

If in doubt, take the piece to a local jeweler for an acid test. Most will test while you wait at minimal cost.

Hallmark Systems by Country

Country	Gold Marks	Silver Marks	Notes
🇺🇸 USA	10K, 14K, 18K, 22K, 24K	925, SS	Karat system; FTC requires accuracy within ½ karat
🇬🇧 UK	375 (9K), 585 (14K), 750 (18K)	925, 958	9K legal minimum; assay offices add date/office letters
🇮🇹 Italy	750, 585, 375	925, 800	Millesimal fineness; "Italy" or "ITA" added for origin
🇩🇪 Germany	750, 585, 333	925, 800, 835	333 = 8K gold (33.3%) — not sold as gold in UK/US
🇫🇷 France	750, 585	925, 800	Also uses eagle/owl head hallmarks from official assay
🇮🇳 India / Middle East	916, 750, 585	925	22K (916) most common; BIS hallmarking mandatory in India since 2021

📖 Complete Jewelry Hallmark Reference Guides

Gold Hallmarks
18K — 750 Gold (75% pure)
14K — 585 Gold (58.3% pure)
417 — 10K Gold (41.7% pure)
750 — 18K European Hallmark
585 — 14K European Hallmark
375 — 9K Gold (UK/AU)

Silver & Plated Hallmarks
925 — Sterling Silver
925 Italy — Italian Silver
HGE — Heavy Gold Electroplate

Frequently Asked Questions

What are jewelry hallmarks?

Jewelry hallmarks are small stamped marks that certify a metal's purity. Gold marks include karat numbers (10K, 14K, 18K) or European fineness numbers (417, 585, 750). Silver uses 925 for sterling. Plated pieces show GP, HGE, or GF.

What does 925 mean on jewelry?

925 means 92.5% pure silver — sterling silver. It's the global standard for silver jewelry. The remaining 7.5% is usually copper for hardness. See our full guide: what does 925 mean.

What does 750 mean on jewelry?

750 means 75% pure gold — the European millesimal fineness mark for 18K gold. A piece stamped 750 is identical in purity to one stamped 18K. Full guide: what does 750 mean.

What does 585 mean on jewelry?

585 means 58.5% pure gold — the European mark for 14K gold. Identical to 14K. Full guide: what does 585 mean.

What does 417 mean on jewelry?

417 means 41.7% pure gold — the European mark for 10K gold. The minimum karat legally sold as gold in the US. Full guide: what does 417 mean.

What does 375 mean on jewelry?

375 means 37.5% pure gold — the hallmark for 9K gold, used mainly in the UK, Ireland, and Australia. Not legal as gold in the US. Full guide: what does 375 mean.

What does HGE mean on jewelry?

HGE = Heavy Gold Electroplate. The piece has a thick electroplated gold coating over a base metal — it's not solid gold. Full guide: what does HGE mean.

How do I know if jewelry is real gold?

Look for a karat stamp (10K, 14K, 18K) or European fineness (417, 585, 750) inside the band or near the clasp. GP, GF, or HGE stamps mean plated/filled — not solid gold. No stamp at all = request documentation or a professional acid test.

What does 925 Italy mean on jewelry?

925 Italy means 92.5% pure sterling silver, made in Italy. Same purity as any 925 stamp — the "Italy" indicates country of manufacture. Full guide: what does 925 Italy mean.

What is the difference between 14K and 18K gold jewelry?

14K = 58.3% gold (European mark: 585). 18K = 75% gold (European mark: 750). 18K has richer color and is more hypoallergenic. 14K is harder and better for daily-wear rings. Most US engagement rings are 14K. Most luxury fine jewelry is 18K.

Your Complete Hallmark Reference

Every piece of fine jewelry carries a story in those tiny stamps. 750 tells you it's 18K gold made to European standards. 925 Italy tells you it's sterling silver from one of the world's finest jewelry-making traditions. GP tells you there's a gold layer — but underneath is something less precious. Understanding these marks makes you a more confident buyer and helps you care for your jewelry the right way.

Browse our full collection of 18K gold plated 925 sterling silver jewelry →

Written by Vaishakhi Ajmera, founder of AJLuxe — specialists in 18K gold plated sterling silver jewelry. Last updated: June 2026.