A guide to hallmarks in gold rings

What is a hallmark?

A hallmark is the official quality control mark or series of marks that determines purity of gold and other precious metals. The four main precious or noble metals that are hallmarked are gold, silver, palladium, and platinum. Hallmarked jewellery is independently tested and marked to assure it conforms to the legal standards of metal purity. In the UK, it’s a legal requirement for Assay Offices to hallmark precious or noble metal objects of a certain weight.

Hallmarks are tested and marked by Assay Offices. Assay Offices are institutions set up to test the purity of precious metals. There are four Assay Offices in the UK, located in Birmingham, Edinburgh, London, and Sheffield. Jewellery and other metal objects (like cutlery) are hallmarked so customers know what they’re buying, and the quality of the metal. It’s impossible to tell the content of a precious metal by looking at it or feeling it, so having a universal mark on a piece of jewellery gives customers assurance that the metal is genuine.

Now that you know why hallmarking is done, we’ll take you through the types of hallmarks and what they tell you about a piece of jewellery.

Types of hallmarks

Hallmarks are typically set in a horizontal line and consist of three compulsory stamps. From left to right, the traditional hallmarks consist of the maker’s mark, the fineness mark, and the Assay office mark. Any other hallmarks included on a piece of jewellery are optional. 

These hallmarks are upheld by the Vienna Convention on the Control of the Fineness and Hallmarking of Precious Metal Objects. This was signed by multiple European countries in an attempt to standardise the legislation on precious metal inspections. Some countries have their own hallmark types if they haven’t signed the Convention. Countries who use the below hallmarks include Austria, Cyprus, Denmark, Finland, Hungary, the Netherlands, Norway, Poland, Portugal, Sweden, Ukraine, and the UK – to name a few.

The maker’s or sponsor’s mark represents the company who made the jewellery or who submitted it for hallmarking. Each jewellery company is registered and comes with their own unique hallmark. This mark helps customer trace their pieces back to their original source.

The fineness or purity mark explains the metal content of each piece. The mark denotes the lowest standard of alloy content found during testing. This is expressed in parts per thousand rather than carat numbers. For example, if a piece of gold jewellery is 9ct, it will be written as 375 on a hallmark. The current standards for each metal is: 14ct gold is written as 585, 18ct is 750 and 22ct is 916. Sterling silver is written as 925, Britannia silver is 958 and platinum or palladium is noted as 950. 

The Assay Office mark explains where the jewellery was assayed. As explained above, there are four Assay Offices in the UK. Each Assay Office have their own stamp to represent them. Birmingham uses an anchor, London’s is a leopard, Sheffield has a rose and Edinburgh’s stamp is a castle.

Optional hallmarks are commemorative marks, traditional fineness marks, convention marks and date letter marks. The two popular optional hallmarks you might see on modern jewellery are commemorative and date marks. Commemorative marks represent national events, like the Silver, Golden and Diamond Jubilee. The date letter identifies the age of a piece of jewellery through a letter. Every year, a new date letter stamp is created so each year is represented by a letter. For example, the date letter for 2020 was a lowercase ‘v’ and a lowercase ‘w’ represents 2021.

How hallmarking is done: testing & stamping

The Assay Offices use a variety of techniques to test the quality of jewellery. The modern technique for testing is X-Ray Fluorescence Spectroscopy, which is a non-destructive technique that measures the metal content. Other techniques include the touchstone method or the fire assay method. Touchstone includes cutting, drilling, or scraping the metal to find its content. This method is rather destructive and isn’t widely used anymore. Fire assay melts the metal or jewellery piece to separate the alloys and weigh them. This is another destructive method, so it’s no longer used to measure jewellery.

To stamp or etch the hallmark into the metal, there are two main ways to do this: stamp or laser. Stamping is done by punching the hallmarks into the metal using steel punches. This technique is best used to mark rings on a straight or ring shank. This technique can displace or distort the metal which means ‘re-finishing’ needs to happen to the jewellery after its hallmarked. The laser technique is the modern method and a more delicate way to hallmark jewellery. Laser marking is done by using high-power lasers that evaporate material from the metal surface. This can be done by 2D or 3D laser marking. The first burns the outline of the hallmark and the latter simulates the marks made by stamping.

On jewellery, a hallmark is often stamped on the back of necklaces or earrings, the inside band of rings or on jewellery clasps to avoid disrupting the design.

Auree Jewellery’s hallmarked gold rings

Hallmarking is extremely important to Auree Jewellery. All our gold and silver jewellery is stamped with our unique Auree maker’s hallmark and the London Assay Office mark which is where all our pieces are checked. Our gold rings are stamped on the inside of the band, not interfering with the beautiful design of the ring or any engravements. Auree Jewellery’s collections – especially our rings – are extensively checked and tested to ensure their quality and assure our customers that we use the best metals to create our beautiful pieces.

Looking for the next ring in your jewellery collection? Take a look at our contemporary yet classic rings made from high-quality gold and silver.

Image credits: theassayoffice.com