Hallmarked Jewellery

A Closer Look

When investing in valuable jewellery, ensuring that pieces are genuine is unsurprisingly the primary concern. Since we are unable to determine fineness (the percentage of purity) by sight or touch alone, we must look for the hallmark.

The hallmark can be defined as a series of symbols that are engraved into genuine gold, silver, platinum and palladium jewellery to demonstrate purity and guarantee authenticity. While it is common to combine pure metals with less valuable forms to enhance the colour, durability and flexibility of jewellery, UK regulations state that a minimum amount of the pure metal is required within the alloy for the piece to be truly deserving of its precioustitle.

Every piece of hallmarked jewellery is independently tested and marked to ensure that it abides by the legal standards of purity. In other words, hallmarking protects jewellery buyers and suppliers from fraud, giving them a clear awareness of the materials used and full confidence that what they’re buying is 100% authentic.

Hallmarks Explained

A full traditional hallmark jewellery sign is made up of 5 key symbols which you will find in a horizontal line on the inside of a ring or any other inconspicuous location on other pieces of jewellery. Think of it like a diamond certificate, but with extra details:

1. Sponsor’s Mark for jewellery manufacturers to put their mark on a piece, quite literally. This mark is uniquely registered to them and is formed by the initials of a company or person.

2. Traditional Fineness Mark to clearly state the precious metal used. There are distinctive symbols for gold, silver (sterling), silver (Britannia), platinum and palladium.

3. Millesimal Fineness Mark to display the quality of metal. Introduced in 1999, the numerical format denotes the precious metal content, expressed in parts per thousand. The current standards for each metal is as follows:

Gold – 9ct (375), 14ct (585), 18ct (750) and 22ct (916).

Silver – sterling silver (925) and Britannia silver (958)

Platinum – 950

Palladium – 500 and 950

4. Assay Office Mark to tell you exactly where your jewellery has been tested for purity. There are only 4 assay offices in the UK with the following symbols: Anchor (Birmingham), leopard (London), Tudor rose (Sheffield) and castle (Edinburgh).

5. Date Letter Mark to indicate the year when the item was hallmarked. Every year on the 1st January, a new date letter stamp is created. This is no longer compulsory, so you will find less modern pieces with their date displayed.

The Hallmarking Process

In order to establish the type of metal and verify the purity of an item of jewellery, a scratch of metal is taken to be analysed by an assay office. Once this has been determined, they will stamp or laser the hallmark symbols onto the piece.

Nowadays manufacturers opt for the laser option since stamping can compromise the durability and change the shape of more delicate pieces (such as metal that has been hollowed out or sleeker ring styles). The downside to lasering is that the hallmark can be easily polished out, in which case a piece would have to be returned to an assay office for a reassessment if sold again.