Metal Guide - A Guide to Metal Hallmarks


A hallmark is an official mark struck on items made of precious metals. This guarantees the purity/fineness of the metal. Hallmarks are a legal requirement on products of a certain weight – depending on the metal being marked. These are incredibly important to us at H.Samuel. You'll have seen the term briefly mentioned in many of our guides.

The Reason for Hallmarks

Gold and silver are expensive in their pure forms and are too soft to be used for jewellery, so they are mixed with other metals known as alloys, to make them affordable and stronger. Platinum's density and weight means when combined with other metals it makes it easier to craft. Palladium is rarely used in its purest form, with alloys added it achieves the desired strength and durability.

It can be tricky to see the physical difference between metals such as white gold, platinum and palladium, as they can be very similar in colour, but do vary dramatically in price.

The only reliable guarantee, to ensure the metal purity/fineness has been reached is for the product to be sent to an Assay Office, where it will be tested before being struck with the relevant hallmark.

How to Recognise Hallmarks – what to look out for

A hallmark consists of three parts, which was made compulsory from 1st January 1999:

  1. The Sponsor's mark
  2. The Standard mark
  3. The Assay Mark
  1. The SPONSOR'S mark (maker's mark): This symbol indicates the individual or firm, accountable for sending the item to assay. Anyone can do this, from manufacturers, retailers to hobbyists. The sponsor must register this mark and pay a fee at any of the four offices.

    • After ten years, the registration must be renewed.

    Typical sponsor marks seen:

    A change in the Hallmark Act, now allows jewellery to be marked with its company logo or brand name.

  2. The STANDARD mark will indicate the fineness of the metal in parts per thousand, this will tell you the percentage of pure gold, silver, platinum or palladium used in the article. The shape of the shield around the number will tell you what metal it is:

    • Silver = Oval
    • Gold = Oblong with cut corners
    • Platinum = Five sided 'house shape'
    • Palladium = 3 adjoining circles (after 2010)
  3. The ASSAY or 'town' mark. There are only four Assay Offices in the United Kingdom, and each one holds their own hallmark symbol, telling the consumer where the article has been assayed (tested).

Articles Exempt for Hallmarking

Items of minimum fineness, weighing less than the following will not carry a hallmark:

  • Gold weighing less than 1 gram
  • Silver, weighing less than 7.78 grams
  • Platinum weighing less than 0.5 gram
  • Palladium weighing less than 1 gram

OPTIONAL or VOLUNTARY marks – It is up to the sponsor to request these.

Date letter: This tells you the year in which the item was tested and hallmarked. Only 25 letters of the alphabet are used. A date letter changes in January and runs in alphabetical order. Once all letters have been used, the font will be changed. All four Assay offices use the same font and letter.

Traditional Pictorial Marks: No longer compulsory – a lion head was used on sterling silver and the figure of a woman for Britannia Silver. A crown was used for gold articles.

Commemorative Marks: These are introduced to commemorate significant events, such as:

  • A millennium mark (available 1999/2000)
  • A Golden Jubilee mark in 2002
  • A Diamond Jubilee mark in 2012

International Convention on Hallmarking

International convention mark is not limited to Britain. The convention mark will be recognised by all members within the International convention.

This will mean that articles bearing a convention mark from other countries are legally recognised in the UK, so will not have to be re-hallmarked again here in the UK.

The convention hallmark shows a pair of scales with the fineness of the metal used; this will be stamped in the middle.