All About Hallmarks: What to Look for When Buying Jewellery


What are hallmarks and what should you look for when investing in a new piece of jewellery?

When choosing an important piece of jewellery made from a precious metal, you should always make sure there is a visible hallmark. Here’s what hallmarks mean and what to look for.

What is a hallmark?

A hallmark is an official mark struck onto items made from precious metals (gold, silver, platinum and palladium). This guarantees the purity, or ‘fineness’, of the piece.

Regulations in the UK dictate that the four main precious metals must contain a minimum amount of pure metal to be classified as ‘precious’. Hallmarks are a legal requirement on products of a certain weight, depending on the metal being marked.

Why are hallmarks important?

The main reason for hallmarks is to provide consumer protection. Sadly, the high price of precious metals means there is a serious risk of fraud. For instance, a thick plating of gold could easily cover a basic metal interior. It’s often impossible to tell from sight or touch alone whether or not a piece being sold is really as described.

Hallmarking is a stamp of quality, helping consumers and suppliers ensure that jewellery items are genuine.

Who applies them?

Hallmarks can be applied only by the Government Assay Offices.

Assay Offices test the purity of precious metals to protect consumers from buying fake items. If an item conforms with the legal requirements for purity, the Assay Office marks it with the appropriate hallmark.

The offices are based in Birmingham, London, Sheffield and Edinburgh.

Two types of hallmarks

There are two main types of hallmarking – stamp and laser. Traditionally, the mark was stamped into items of jewellery, which was not always ideal because it could damage hollow or delicate pieces.

Nowadays, most manufacturers opt for the laser hallmark. It does not distort the jewellery and is usually very subtle.

How to recognise a hallmark

A hallmark is made up of three parts (made compulsory from 1st January 1999). They comprise:

1. Sponsor’s mark

The sponsor’s or maker’s mark symbol indicates the individual or firm accountable for sending the item to assay. The sponsor must register this mark and pay a fee at any of the four offices. After ten years, the registration must be renewed.

2. Standard mark

The standard mark indicates 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 item. The shape of the shield around the number will indicate what metal it is:

  • Silver – oval
  • Gold – oblong with cut corners
  • Platinum – five-sided ‘house shape’
  • Palladium – adjoining circles (after 2010)
3. Assay or ‘town’ mark

Each of the UK’s four Assay Offices holds its own hallmark symbol. This lets the consumer know exactly where the article has been assayed (tested).

There are also three optional or voluntary marks. It is up to the sponsor to request these:

1. Date letter

This shows the year the item was tested and hallmarked. Only 25 letters of the alphabet are used.

2. Traditional pictorial marks

A lion’s head was once used on sterling silver and the figure of a woman for Britannia Silver. A crown was used for gold articles. These marks are no longer compulsory but you may see them on vintage pieces.

3. Commemorative marks

Special marks are sometimes introduced to commemorate significant events. For example, a new commemorative mark has been designed to celebrate Her Majesty the Queen’s Platinum Jubilee.

Buying jewellery abroad

Hallmarking is standard practice in the UK but it’s not mandatory everywhere in the world.

In the US for instance, hallmarking is not a legal requirement. Many US jewellery collectors instead look for certain maker’s marks for assurance that a piece is of high quality.

If the piece of jewellery you’re looking at has been made abroad, then it might have an international assay office mark present. The International Convention is a group of countries who have their own strict rules on hallmarking. This means that each country within the group recognises the hallmarks of the other members as being legitimate. Here is a list of members, plus their most common assay mark:

Austria – a bold ‘W’ shape on a tri-headed shield

Cyprus – a boat with sail

Czech Republic – a capital ‘P’ in a square

Denmark – an oval mark containing three towers

Finland – a crown within a heart

Hungary – a capital ‘H’ in an oblong box

Ireland – a figure sitting facing to the left

Israel – a simple flower or stringed instrument

Latvia – a crowned woman facing left within a diamond shape

Lithuania – a man on a horse holding a sword

The Netherlands – a horse head within a circle or a NL ASSAY OFFICE round stamp

Norway – a heraldic lion facing left within a circle

Poland – the Polish crest within a circle

Portugal – a bird or other animal framed with the millesimal fineness mark

Slovak Republic – a partial circle surrounding a twice-crossed line, with ‘SK’ to the left and ‘X’ to the right

Slovenia – the relevant chemical symbol (Au, Ag, Pt) within a shield

Sweden – three crowns outlined in a ‘mickey mouse’ shape

Switzerland – the head of a large dog facing left within an unequal heptagon.

What about buying antique or vintage jewellery?

Hallmarks were not mandatory in the UK until 1972 in the UK, so there are lots of jewellery pieces out there with no date or hallmark.

These pieces of jewellery can usually be given an approximate date based on the style, cut of the gemstones (specifically diamond cuts), type of gemstones and appropriate ‘wear’.

It’s worth noting, too that the Hallmarking Act has changed several times over the years and some items were not previously required to be hallmarked.

These guidelines from the Assay Office will help you decide whether you need to submit your jewellery items for hallmarking.

Protecting your hallmarked piece

If you want to protect a hallmarked piece, consider specialist jewellery insurance from TH March. We can provide you with bespoke jewellery and watch insurance to give you worldwide accidental damage, loss and theft cover for your precious items.