The Complete Guide to British Hallmarks

What Are British Hallmarks and Why Do They Matter?

A hallmark is a set of small symbols stamped (or, more recently, laser-engraved) into an item made of precious metal. Each symbol conveys a specific piece of information: who made the piece, what metal it contains, which assay office tested it, and when. Together, they form an unbroken chain of accountability stretching back more than 700 years.

Unlike many countries where purity marks are self-declared by the manufacturer, British hallmarks are applied by independent assay offices after the item has been scientifically tested. This makes them one of the most trustworthy guarantees of precious metal content available anywhere in the world. Forging a hallmark is a criminal offence under UK law.

The Four Compulsory Marks

Since the Hallmarking Act 1973, every legally hallmarked item must carry at least three compulsory marks: the sponsor’s mark, the fineness (purity) mark, and the assay office mark. The fourth mark — the date letter — was compulsory from the 15th century until 1999, when it became optional. Most offices still apply it, and it remains essential for dating antique pieces.

Sponsor’s Mark (Maker’s Mark)

The sponsor’s mark identifies the person or company responsible for sending the item to the assay office. It consists of initials inside a distinctive shield shape. Each mark is unique and registered with the assay office, so it can be traced back to a specific maker, retailer, or importer. On antique pieces, identifying the sponsor’s mark can tell you exactly who made the item and where they operated.

Fineness (Purity) Mark

The fineness mark shows the precious metal content in parts per thousand. For sterling silver, this is 925. For gold, the most common standards are 375 (9ct), 585 (14ct), and 750 (18ct). Platinum items are stamped 850, 900, 950, or 999. Before 1999, the fineness was indicated by traditional symbols (such as the lion passant for sterling silver) rather than numbers, though both systems now coexist.

Assay Office Mark

This symbol tells you which office tested the item. Each of the four active UK assay offices has its own distinctive mark (detailed below). On antique pieces, you may also encounter marks from the now-closed offices in Chester (three wheatsheaves and a dagger), Exeter (a three-towered castle), or Newcastle (three castles).

Date Letter

The date letter is a single letter of the alphabet that indicates the year the piece was assayed. The letter changes every year and cycles through the alphabet (usually A to U or A to Z, depending on the office and era). Because the same letter is reused across cycles, you must also consider the typeface, case (upper or lower), and shield shape to pinpoint the exact year.

The Lion Passant and Lion Rampant

The lion passant — a lion walking to the left with its right forepaw raised — is the traditional English mark for sterling silver. It was first introduced in 1544 and replaced the earlier leopard’s head crowned as the primary silver standard mark. You will see it on virtually every piece of English sterling silver made in the last 480 years.

Scottish sterling silver uses the lion rampant — a lion standing on its hind legs — as its standard mark, along with the thistle symbol. If you find a lion rampant on a piece of silver, it was assayed in Edinburgh (or, historically, in Glasgow before that office closed in 1964).

Since 1999, the numeric fineness mark (925) can appear alongside or instead of the traditional lion symbols. On modern pieces, you may see both the lion passant and “925” together, or just the number.

Assay Office Marks: London, Birmingham, Sheffield, and Edinburgh

London — The Leopard’s Head

The leopard’s head has been London’s assay office mark since 1300, making it the oldest hallmark in continuous use. Originally depicted crowned, it lost its crown in 1821. The mark is technically a heraldic leopard (which in medieval heraldry meant a lion shown face-on), so do not confuse it with an actual leopard. Pieces bearing this mark were tested at Goldsmiths’ Hall on Foster Lane in the City of London.

Birmingham — The Anchor

The anchor mark was adopted by the Birmingham Assay Office when it was established in 1773. Legend has it that Matthew Boulton and his associates chose the anchor because their campaign for a local assay office was discussed at the Crown & Anchor tavern in London. Birmingham is the busiest assay office in the world, testing over 12 million items per year.

Sheffield — The York Rose

Sheffield’s mark was originally a crown, used from the office’s founding in 1773 until 1975. Because the crown was easily confused with gold fineness marks, Sheffield switched to the York rose (a Tudor rose) in 1975. If you see a crown on a Sheffield piece, it predates 1975; a rose means it was assayed after that date.

Edinburgh — The Castle

Edinburgh’s assay office mark is a three-towered castle, representing Edinburgh Castle. It has been in use since 1485. Items bearing this mark were assayed in Scotland under separate Scottish hallmarking legislation, which was eventually harmonized with the English system under the Hallmarking Act 1973.

Gold Fineness Marks: 375, 585, 750, and 916

British gold items carry a fineness mark that indicates the gold content in parts per thousand. The most common standards you will encounter are:

• 375 — 9 karat gold (37.5% pure gold). The most common standard in British jewelry, particularly for everyday items.
• 585 — 14 karat gold (58.5% pure gold). Less common in British-made pieces but frequently seen on imported items.
• 750 — 18 karat gold (75% pure gold). The standard for high-end British jewelry and watch cases.
• 916 — 22 karat gold (91.6% pure gold). Historically used for gold coins and wedding bands; less common in modern jewelry due to softness.

Prior to 1975, gold items carried a crown symbol alongside a karat stamp (e.g., “18” for 18ct) rather than the millesimal fineness number. After 1975, the numeric system became standard. Many transitional-period pieces carry both formats.

How to Read a Complete Hallmark Sequence

When you find a set of hallmarks on a piece of silver or gold, read them from left to right. A typical sequence on an English sterling silver piece might look like this:

1. Sponsor’s mark — Two or three initials in a shaped shield (e.g., “JB” for a specific silversmith).
2. Lion passant — Confirming sterling silver (925).
3. Assay office mark — For example, the leopard’s head (London) or anchor (Birmingham).
4. Date letter — A single letter indicating the year of assay.

On gold items, the lion passant is replaced by the appropriate fineness mark (375, 585, 750, etc.), and you may see a crown symbol on pre-1975 pieces. The order is generally consistent, but slight variations exist — especially on items with limited stamping space like rings, where marks may be spread around the inside of the band.

Common Mistakes When Reading Hallmarks

• Confusing the leopard’s head with a cat or lion. The London assay office mark is officially a leopard’s head, but it resembles a frontal view of a lion’s face. It is not a cat, panther, or tiger.
• Assuming all lions are the same. The lion passant (walking) means sterling silver in England. The lion rampant (standing) means sterling silver in Scotland. They are different marks applied by different offices.
• Using the wrong date letter chart. Each assay office has its own letter cycle and shield shapes. A letter “B” in Birmingham means a different year than a “B” in London.
• Mistaking plating marks for hallmarks. Electroplated items are often marked “EPNS” (Electro Plated Nickel Silver) or “EP”. These are not hallmarks and do not indicate precious metal content. Silver-plated items have no legal hallmark.
• Expecting worn hallmarks to be clear. On heavily worn antique pieces, hallmarks may be partially rubbed away. A jeweler’s loupe and good lighting are essential for examination.