In the realm of jewellery, where quality meets craftsmanship, there exists a silent but essential guardian – the hallmark. Like a secret code etched into each piece, a hallmark tells a story of authenticity, quality, and tradition.

What is a hallmark?

A hallmark is a set of component marks which verify a product's material. Precious metals are rarely used in their purest form, instead being mixed with other metals to make them more durable. Hallmarks are only applied to precious metals Platinum, Gold, Palladium and Silver.

It isn't possible to detect an article's precious metal content by sight or touch, therefore it is a legal requirement for items being sold as precious metal, over a certain weight, to bear a hallmark. All Silver items that weigh less than 7.78g do not require a hallmark.

Hallmarks are applied to precious metals to indicate the amount of pure metal in a product. Traditionally applied by striking with a punch, hallmarks can now also be applied using lasers.

It is illegal to sell a precious metal product without a hallmark and non-precious items are not permitted to have a hallmark. Items with just 925 are not legally hallmarked as they are missing the other marks.

Something being sold in the UK without a hallmark is breaking the law and there is a high chance the item may not be made from precious metal.

Every Serge DeNimes ring, necklace & bracelet has been verified by the Goldsmiths Company Assay Office in London, which means you can trust that every item you buy from us is made from Sterling Silver, as they have provided independent quality assurance. Earrings are also made from 925 Sterling Silver however they are under the weight limit and therefore do not need to be tested and hallmarked. Our factory tests these before shipping as part of our quality control.

Sponsors mark

Shows the company that made the product. Ours is 'SDN'.

Fineness mark

The symbol shows that the product is made from sterling silver.

Millesimal Finess Mark

This shows the purity of the metal.

Assay Office Mark

This is the mark of the London Assay Office.

Year Mark

This shows the year that the article was marked.

There are 2 types of Hallmark; The Traditional Hallmark is all 5 Marks | The Minimal Hallmark is just 3 of the marks. The sponsors mark, the millesimal mark & the office mark.


Find out what a hallmark looks like here.

First, the article must be tested to see what materials it is made of. There are a few different ways to do this, shown here is the X-Ray Fluorescent Spectrometer test.

Another method is the 'touch test', this technique dates back to 500BC. The article is gently rubbed against a 'touchstone' made from basonite.

This leaves a small mark on the stone. Chemicals are applied to the mark and from the reaction that takes place, an initial indication of the fineness is determined. This is the origin of the phrase 'coming up to scratch'.

Most of our products are Hallmarked using lasers, however this specific piece (Silver Traditional Hallmark Bangle) has been designed to be struck by hand.

Handmarking is the most traditional method of hallmarking and is carried out using a punch and hammer, this hallmark will last a lifetime.

On necklaces, hallmarks can be found by the clasp.