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

By Dmitry Strugovshchikov, founder of STRUGA

A 925 stamp claims a fineness of 925: 92.5% silver by mass. The number alone does not authenticate the object. A compulsory British hallmark has three parts: a registered sponsor’s mark, a fineness mark and an assay office mark. Other countries use different systems. Read the system before drawing a conclusion from the stamp.

925 means 92.5% silver, 950 means 95% and 999 means 99.9%. These figures describe alloy content, not design, finish or country of manufacture.

Britannia silver is marked 958. The British standard requires at least 958.4 parts silver per thousand; 950 is a different fineness.

A British sponsor’s mark identifies the registered person or company submitting the piece. It does not necessarily identify its manufacturer.

A stamp, colour, magnet or weight alone cannot establish silver fineness. Read official mark records for identification and use professional analysis when the alloy itself is in question.

Updated October 13, 2026

If you are choosing a ring, start with the material and size in the Thorn Ring | STRUGA listing, then compare the complete marks on your object. This guide explains marking. The Atlas of 925 Silver explains the material and how it behaves; those are different questions.

What do real silver hallmarks look like?

A ring may carry little more than a number. An old English tray can carry initials, a lion, a leopard's head and a human profile in one row. Start by recording the complete set, then find the reference for its country and period. These three photographs show why a fineness number and a full assay hallmark provide different information.

What can you read from a 925 mark inside a ring?

The left ring reads “925” and “MEXICO”; the right reads “925”. You can transcribe those inscriptions, but the photograph does not identify an assay office that tested the object. The number states fineness; the word beside it is a separate inscription. Establishing origin and authenticity needs evidence about the particular piece.

How do you read a row of British marks?

Five marks appear in a row. Reading from left to right:

• PS — initials; the photographer attributes the tray to Paul Storr.
• A lion passant — the traditional British sterling silver symbol.
• A leopard's head — the London assay office mark.
• The letter u in a shield — a date letter, matched by typeface and outline to the correct period's chart.
• A human profile — the historical duty mark.

The London Assay Office's guide explains the traditional symbol, office mark and date letter. Its hallmarking history also describes the duty mark, introduced in 1784 and withdrawn in 1890. Do not judge this older row solely by today's three compulsory components. Numerical fineness became compulsory in British hallmarks in 1999.

What can old Moscow marks tell you?

The marks on this cup are worn. The museum associates them with an unidentified maker using the initials VD, assayer Andrei Zaitsev and Moscow in 1745. Its record of the particular object gives us more than a guess based on a familiar-looking letter. We do not assign modern 925 fineness from this photograph or present the marks as examples of current Russian marking.

For your own piece, photograph the whole row in the same way: numbers, initials, symbols and their outlines. Separate the findings — fineness, the person responsible for a mark, place and date. The table below explains numerical silver standards; the other evidence establishes country and period.

What do 925, 950, 958 and 999 mean?

Silver fineness is expressed in parts per thousand by mass. In a 925 alloy, 925 parts are silver and the remaining 75 are other constituents. The number does not identify every alloying element. The Royal Society of Chemistry’s silver reference gives Ag as the element symbol and describes sterling as silver with copper or another metal. Sterling is the familiar name for silver containing at least 925 parts per thousand: that threshold also appears in the US Federal Trade Commission’s silver guidance.

Is Britannia silver 950 or 958?

Britannia silver is 958, not 950. More precisely, the British standard requires 958.4 parts silver per thousand, while the numerical mark reads 958. This explains the rounded “95.8%” found in short guides. The fineness minimum and numerical mark are specified in the Hallmarking Act 1973. A 950 silver alloy contains 95% silver and does not meet that Britannia minimum.

Also check which metal a number describes. A 950 mark can appear on platinum. Its surrounding shape and the rest of the hallmark matter; a silver conversion table cannot identify every object stamped 950.

Which silver fineness works for jewellery?

For a ring, fineness and construction both matter. A 925 designation identifies a familiar jewellery alloy, but fit also depends on the ring’s width, profile, size and mass.

Pure silver is soft, and alloying is used to change its properties. The UK government’s buyer guidance explains why precious metals are alloyed for strength. That does not mean every 999 ring must fail or every 925 ring will resist any force. Shape and the condition of the metal also affect an object’s behaviour.

925 versus 950 compares the silver proportion; it is not a finished ranking of workmanship. Choose the construction for the way you wear the piece and read the number for its stated fineness. Our separate guide to choosing silver purity for jewellery follows the material question further.

How do you identify silver hallmarks by country?

Identify the system first. A British assay hallmark, a Russian manufacturer’s mark and a US silver designation are not interchangeable. There is no universal rule that a pair of letters beside 925 authenticates an object.

British hallmarks: the three compulsory parts

The London Assay Office’s hallmark guide distinguishes the sponsor’s mark, numerical fineness and assay office mark from the optional date letter and traditional metal symbol. A modern hallmark without a date letter can therefore be complete.

In the British system, the lion passant is the traditional symbol for Sterling 925; the Britannia figure refers to 958. The Sheffield Assay Office lists these traditional symbols as optional additions. They do not replace reading the compulsory parts of the mark.

Small articles can be exempt from compulsory UK hallmarking. For silver, the weight exemption applies below 7.78 g of total metal weight, with the conditions set out in the hallmarking exemption regulations. Read the exemption precisely; a missing hallmark on a small object is not by itself proof of a false silver description. The rule does not turn a seller’s claim into an assay result.

Russian silver and the United States

For silver jewellery manufactured in Russia, state hallmarking has been voluntary since June 2020, according to the Federal Assay Chamber. Manufacturers are separately required to register their manufacturer’s marks, or imenniki; the official registration procedure explains that requirement. The domestic-silver rule must not be extended automatically to imports or other metals.

US FTC guidance allows Sterling and Sterling Silver descriptions at no less than 925 parts silver per thousand. Silver-coated base metal must be described as coated; silver at the surface does not turn the underlying metal into a silver alloy. For French, Mexican or other historical marks, use the appropriate country and period reference. A symbol remembered from another system is not enough.

What does a maker’s or sponsor’s mark establish?

A registered mark helps identify a responsible person or company. It is useful evidence for identification, but it does not independently measure the alloy or prove that the mark on this particular object is genuine.

The British sponsor can be a manufacturer, retailer or another registered submitter. Calling every sponsor’s mark a workshop signature is therefore misleading. Compare the initials together with their outline: letters without the right surrounding shape can point to the wrong registration.

For a Russian manufacturer’s mark, use the Russian registration system. For a British sponsor’s mark, use the relevant assay office records. The questions “who owns this registered mark?” and “what is this object made of?” require different evidence.

How do you check a suspicious silver stamp?

A home check can reveal a question worth investigating; it cannot reliably assign 925, 950 or 999 fineness. Start with the complete mark and the material description. If composition is disputed, professional analysis is more useful than escalating to stronger household chemicals.

The London Assay Office offers X-ray fluorescence, or XRF, for alloy-composition reports as well as other laboratory methods. Its laboratory services guidance describes XRF as usually non-destructive, with an exception for heavily plated objects. Ask what was examined and how the method deals with a coating. A surface result must not be assumed to describe an inaccessible core or every component of an assembled piece.

Weight is not an authenticity test. Hollow and solid rings, a broad plane and a narrow line can have different masses at the same fineness. Household weighing does not justify declaring that an object is “not 925”. The separate guide to checking whether silver is real covers the identification question and its limits.

What can’t a hallmark tell you?

925 does not name the designer, describe the fit or identify the finish. Fineness concerns metal content; surface treatment is a separate description. Bright surfaces and dark recesses do not automatically mean different silver purities.

Place is separate too. “Bali silver” describes geographic context, not a special silver percentage. To compare a piece from Bali with a British or Russian piece, read its stated material, construction and the applicable marking system. Geography cannot substitute for an assay.

How do STRUGA silver rings compare?

STRUGA was born in Bali. For the international market, STRUGA objects are made in Bali. Check each product listing for its material; one silver ring does not describe every material in the catalogue.

The comparison below uses silver rings in catalogue size 18 and lists their current masses. These figures help compare constructions; they do not verify fineness or authenticity. Use the product listing for any other size.

Thorn’s sharp planes, Triple Drills’ repeated openings and Signature Links’ open links give different structures. Where the material matches, the choice continues through form and fit. Compare more forms in the CODEX world or ring catalogue; use the Atlas of 925 Silver for material properties.

How do you read the marks on your own jewellery?

1. Photograph the full set of marks together, then each mark separately. Keep their outlines and neighbouring symbols in view.
2. Write down the number exactly. Record initials, outlines and symbols separately: 950 and 958 are different entries.
3. Identify the likely marking system from the complete set. Do not assign a country from a fineness number alone.
4. Match the sponsor’s or manufacturer’s mark to the appropriate official record. A British date letter needs that office’s date chart.
5. Separate what you read from what you infer: stated fineness, a matched registration and a composition test are different findings.
6. If the question concerns metal content or plating, seek professional analysis and clarify the part and method examined.

A hallmark answers only part of the question. The number indicates claimed fineness; a registered mark can identify a responsible person or company. Form and fit still have to be assessed on the hand.