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MyPiece·Hallmarks·United Kingdom
Reference·Independent assay

United Kingdom

Britain's hallmark is a row of tiny stamps, struck only after independent testing, that certify who made a piece, how pure it is, and where it was assayed. It is the oldest consumer protection of its kind.

In the atlas: Hatton Garden · Birmingham Jewellery Quarter

The system

Independent assay

Hallmarking began at Goldsmiths' Hall in London in 1300 — the source of the word itself. Four assay offices still test and strike every qualifying article.

Compulsory independent assay since 1300 — the world's oldest system.

Anatomy

One line, six marks

A worked example: a sterling-silver piece by maker MP, assayed in London. The first three marks are compulsory; the last three are optional.

  1. MP
    01 · CompulsorySponsor's markThe registered initials of the maker or company that submitted the piece.
  2. 925
    02 · CompulsoryFineness markThe millesimal number — parts per thousand of precious metal (925 = 92.5% silver).
  3. 03 · CompulsoryAssay office markWhich of the four offices tested and struck the piece — London, Birmingham, Sheffield, Edinburgh.
  4. 04 · OptionalStandard symbolThe traditional pictorial mark of the metal and standard — lion, Britannia, crown, orb, or Athena.
  5. n
    05 · OptionalDate letterA single letter, in a font and shield that change each year, recording the year of assay. Optional since 1999.
  6. 06 · OptionalCommemorative markStruck only for special years — a coronation or jubilee — by request.
The marks

What you'll see struck

Leopard's Head

Since 1300

London Assay Office

The Goldsmiths' Company office, marking since 1300. Crowned until 1821, uncrowned since.

Anchor

Since 1773

Birmingham Assay Office

Founded by Act of Parliament in 1773; said to derive from the Crown & Anchor tavern.

Rose

Rose since 1975

Sheffield Assay Office

Also 1773. The town mark was a crown until 1975, then the Yorkshire rose.

Three-towered Castle

15th c.

Edinburgh Assay Office

Scotland's office. The castle is the town mark; the standard symbol beside it is a lion rampant.

Lion Passant

Sterling silver (925)

A lion walking, facing left — the centuries-old English mark for sterling. Scotland uses a lion rampant.

Britannia

Britannia silver (958)

The seated figure of Britannia marks the higher 95.8% standard, introduced in 1697.

Crown

Gold standard symbol

The traditional English symbol for gold, struck beside the carat number.

Orb

Platinum standard symbol

An orb and cross marks platinum, struck since platinum hallmarking became compulsory in 1975.

Pallas Athena's Head

Palladium standard symbol

The helmeted head of Pallas Athena marks palladium, added in 2010.

Standards

Fineness

Gold
375 (9ct) · 585 (14ct) · 750 (18ct) · 916 (22ct) · 999
Silver
800 · 925 (sterling) · 958 (Britannia) · 999
Platinum
850 · 900 · 950 · 999
Palladium
500 · 950 · 999
Tool

Hallmark Calculator

See how United Kingdom's standards line up with any other country — translate a grade, or compare side by side.

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Sources & references
  • London Assay Office — What is a hallmark?↗
  • Antiques Trade Gazette — Silver hallmarks↗
  • The Silver Society — Identifying silver↗

A reference guide, not an authentication service. Marks vary by date and metal; consult the relevant assay office or standards body for definitive identification.

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