Silver Hallmarks Explained: 925, 950, 999 Stamps and What Each Mark Means

By Dmitry Strugovshchikov, founder of STRUGA

A "925" stamp is not proof that a piece is real silver, and it is not the part of the mark that certifies it — it is a fineness claim, and a punch and hammer can forge one in seconds. What certifies a silver piece is the maker's mark beside the number: two to four letters that tie the metal to a workshop that has taken responsibility for it. Fineness alone is a metal-content claim without traceability; fineness plus an identifiable maker's mark is provenance.

Updated August 29, 2026

- A "925" stamp is a fineness claim only — not proof of real silver and not the certifying mark; the maker's mark beside it is what ties the metal to a workshop.

- 925 = 92.5% silver with 7.5% copper, written into English law by the Statute of Edward I in 1275. 950 is the French first standard. Britannia silver is 958, not 950. 999 is fine silver — bullion grade, too soft to hold its shape in daily wear.

- Copper is what makes sterling wearable and what makes it darken: Vickers hardness rises from about 30 HV in fine silver to about 75 HV in annealed sterling and about 120 HV work-hardened.

- A full UK hallmark needs three compulsory marks — sponsor's mark, fineness, assay office; the date letter has been optional since 1998 and changes every 1 January.

- Russia does not require a state hallmark on domestically made silver: marking is voluntary, and it is the maker's mark that is compulsory. The UK, France and Mexico do require assay.

- Cheapest forgery test is a strong magnet — sterling silver is non-magnetic, so any attraction means base metal. Sterling density is 10.36 g/cm³ against 10.49 for fine silver and 8.53 for brass.

The marks stamped inside a ring or on the back of a pendant do three jobs: they state the metal content, they identify the workshop, and they tie the piece to a system of guarantees that has run in Europe for seven centuries.

I am Dmitry Strugovshchikov, founder of STRUGA. Every piece in the catalogue is cast in 925 sterling silver in a Bali workshop, and the marking protocol below is the one those benches follow. Where the answer depends on a country's law rather than on a bench habit, the source is named in the text.

What do 925, 950 and 999 actually mean?

A fineness number is parts of pure silver per thousand parts of alloy: 925 means 925 parts silver and 75 parts of something else, almost always copper. The number says nothing about who made the piece or how well.

Mark	Silver	Where you meet it	Daily wear
800	80.0%	Older German and Italian work	Yes, below sterling
835	83.5%	Mid-century Scandinavian silver	Yes, warmer tone
900	90.0%	Coin silver, 19th-century US work	Rare today
925	92.5%	The global jewellery default	Yes — the standard
935	93.5%	Argentium, a modern germanium alloy	Yes, darkens slower
950	95.0%	French first standard	Softer, ceremonial
958	95.8%	Britannia silver, England since 1697	Softer, silverware
999	99.9%	Bullion bars and coins	No — loses shape

Why 958 and 950 are not the same standard

Britannia silver is 958 parts per thousand, not 950. England introduced it in 1697 to stop silversmiths melting coinage, and it is still a legal alternative to sterling. The 950 number belongs to the French first standard. Confusing the two is the commonest error in hallmark guides, and it changes the metal you think you are buying by almost a percentage point.

Why 999 is not a jewellery standard

Fine silver at 99.9% is bullion grade. A 999 ring dents if you drop it on tile and bends if you squeeze it firmly. Higher purity buys a softer object, not a better one.

Why did 925 become the global standard?

Pure silver is too soft to wear. Adding 7.5% copper raises the Vickers hardness from about 30 HV in fine silver to about 75 HV in annealed sterling, and to roughly 120 HV once the metal is work-hardened at the bench. That is the difference between a band that deforms when you grip a steering wheel and a band that survives a decade.

The standard was fixed in law by the Statute of Edward I in 1275, which set the silver content of coinage at eleven ounces two pennyweights per twelve troy ounces — about 926 parts per thousand. Seven and a half centuries later the number has barely moved. Continental workshops were already alloying silver with copper in the 1100s; 1275 is the date the practice became law.

Copper is also the reason silver darkens. The same element that makes the alloy wearable reacts with sulfur in the air to form the brown-grey film. Darkening is not a defect in the metal — it is the price of hardness, and higher-fineness silvers darken slower only because there is less copper to react. The chemistry, and what to do about it, is in the guide on how to prevent silver from tarnishing.

What does each country stamp on silver?

National marking traditions grew up independently, centuries before any international standard. They agree that a stamp should be readable by a stranger; they disagree on whether the state must be involved at all.

Country	State mark	Required?
United Kingdom	Lion passant 925, Britannia 958	Yes, above exemptions
France	Minerva head (950), crab (800)	Yes
Russia	Kokoshnik head with fineness figure	No, voluntary
Mexico	Eagle with office number	Yes
Italy	Fineness number plus province code	Registered maker
United States	"STERLING" or "925"	No
Indonesia	Maker's stamp only	No

The British sequence, and what is actually compulsory

A British hallmark carries three compulsory marks and one optional one, published by the Assay Office London.

• Sponsor's mark — what the trade calls the maker's mark.
• Fineness mark — the millesimal figure or the lion passant.
• Assay office mark — leopard's head London, anchor Birmingham, castle Edinburgh, rose Sheffield.
• Date letter — optional since 1998, changes every 1 January; font, case and shield shift so a letter means one year only.

What Russia actually requires

Russia is the country most often described wrongly in English-language hallmark guides, including in earlier versions of this one. The Federal Assay Chamber states that silver jewellery of domestic manufacture is hallmarked and marked voluntarily and may be sold without a state assay mark — but never without the manufacturer's registered maker's mark, the imennik. The kokoshnik head, a woman's profile in traditional headdress, has been the state mark since 1958 and appears with the fineness figure and an inspector's letter code. Pieces from before 1917 carry earlier eagle, year and city marks.

Why does the maker's mark matter more than the number?

A 925 stamp on its own is unverifiable: the number can be struck with a punch in seconds and carries no information about where it came from. The maker's mark — read together with a workshop's address, reputation and record — is what makes the claim checkable. British law encodes the principle directly: assay offices will not test a piece that does not already carry a registered sponsor's mark. When you look at a piece, the questions run in this order.

1. Is there a fineness mark? "925", "STERLING", or an equivalent. Without it, the metal content cannot be read at all.
2. Is there a maker's mark? Two to four letters or a small geometric symbol beside the number.
3. Can the maker's mark be identified? A findable workshop, not anonymous initials.
4. Is there an assay mark? A state office tested the metal — a layer on top of the workshop's own word.

How do you spot a forged 925 stamp?

Forged fineness stamps are common on marketplace and tourist-market silver. Three of the four tells need no equipment.

• Uneven depth. A workshop punch strikes to a consistent depth. Hand-engraved characters and worn punches leave letters of different weight.
• Wrong place. Real workshops stamp by convention — inside the ring band, the back of a pendant, the clasp tongue of a bracelet. Forgeries appear wherever the punch fit.
• No maker's mark. A fineness number standing alone is the single strongest warning sign.
• The metal behaves wrongly. Base metal, plated metal and silver-coloured alloys all take a stamp.

The three home tests, and what each one proves

Test	What you see	What it proves
Magnet	Any attraction at all	Base metal under the plating
Scale	Sterling 10.36 · brass 8.53 · nickel silver 8.73 g/cm³	Silver against imitation, an 18% gap — not 925 against 875
Nitric acid	Creamy white, or green	Silver, or base metal

Density is the test most often misread: it separates metals, not fineness grades. Fine silver is 10.49 g/cm³ and sterling 10.36, so no kitchen scale will tell 925 from 875.

What do hallmarks not tell you?

The fineness stamp confirms the alloy and nothing else.

• Not construction quality — whether the casting is solid, the soldering clean, the stones properly set.
• Not design originality — many 925 pieces are mass-produced from imported castings and stamped locally.
• Not sourcing — that lives in workshop documents, not in metal.
• Not resale value — that follows reputation, design and condition.

How 925 compares with gold, platinum and steel for wear is set out in sterling silver versus other metals.

How is STRUGA silver marked?

Every object is cast in 925 sterling silver, with no plating and no coating over the metal. For the international market, STRUGA objects are made in Bali.

Indonesia, where the international catalogue is made, has no mandatory assay system: silver there is marked by the maker, and reputation rather than a state office carries the guarantee. The tradition is described in the Celuk village silver guide.

Two surfaces change how marks read. Living Silver is 925 with no rhodium over it: the metal darkens by itself with wear, so a mark that was crisp on delivery sits deeper in tone a year later and grows more legible as the high points rub back. On silver darkened deliberately at the bench — oxidized silver, a choice of surface rather than a change over time — the stamps go in before the darkening and stay sharp under it. A wide band leaves room for a full mark, which is why it reads best on signet rings and on the heavier forms of THORN; on thin bands and openwork the fineness figure stands alone, because a second punch on 1.5 mm distorts the geometry. The Thorn Ring is the wide-band case; both surfaces live inside CODEX.

How do you read the marks on your own jewellery?

Take a piece into good light and use a 10× loupe or a phone camera at maximum magnification. On rings, look inside the band near the bottom; on pendants, at the back near the bail; on bracelets, inside the clasp tongue; on earrings, at the back of the face or along the post.

At minimum you should find a fineness mark — 925, STERLING, 950 or 999 — and on a serious piece a maker's mark beside it. Fineness plus an identifiable maker gives provenance; fineness alone gives a claim. Absence of marks is not proof of forgery, since most Indonesian and much American silver is legally unassayed.

Related reading in this cluster: the pillar guide to sterling silver, what 925 sterling silver is, oxidized silver rings, why silver leaves a green or black mark on skin, the full catalogue, and inside the Bali silver workshop.