All About Hallmarks

Hallmarking is a legal requirement of jewellers, and involves an independent body assessing and certifying the fineness of metal.  It’s not possible to judge this by the way a metal looks or feels, so in order for a customer to know to what extent the precious metal has been alloyed with others for increased strength, wearability, or workability, the hallmark shows the amount of pure metal present.  The practice of hallmarking began in the middle ages.

Hallmarks are used on jewellery containing platinum, gold, palladium and silver, and tell us where the piece was hallmarked, what it’s made from, and who sent it for hallmarking.  It’s legally required for silver over 7.78g, gold and palladium over 1g, and platinum over 0.5g to have a UK recognised hallmark, according to the Hallmarking Act 1973.  

A hallmark is a government seal that’s stamped onto precious metal objects, such as jewellery or silverware. The purpose of a hallmark is to certify the metal purity of the item. Only a UK Government Assay Office can apply a hallmark. Testing precious metals for purity is called “assaying” - hence the name. There are four ‘Assay Offices’ where jewellery is hallmarked in the UK, in London, Sheffield, Birmingham and Edinburgh.  The oldest, Goldsmiths’ Company Assay Office in London, began hallmarking in the year 1327.

Compulsory hallmarking means that the public will always have a guarantee of quality. Likewise, legitimate jewellers are protected from unlawful competitors who might try to pass off low quality jewellery as the “real deal”. The only exception to the law on hallmarking is for extremely light pieces of jewellery that weigh under a certain number of grams (1g for gold, 0.5g for platinum, and 7.78g for silver).  In reality, this means small pieces like earrings.  Otherwise, it’s illegal to claim a piece of jewellery contains a precious metal (even if it does!) if it’s not hallmarked.  It’s also illegal to remove, alter or counterfeit a mark.

Traditionally applied by striking with a punch, hallmarks can now also be applied using lasers. The normal form of a hallmark is a horizontal mark with minimal spacing between the marks, which are 0.5mm-1mm in height.  ‘Feature marks’, which are more complex, take more time and are costly to do.  Many objects are still stamped by hand, exactly as they were 700 years ago. 

Only jewellery that carries an officially registered British or international hallmark can be sold in the UK. A hallmark will usually include the Assay Office town mark such as the London Assay Office, together with 2-4 additional marks, such as a date letter, a metal standard symbol or a duty stamp. There are hundreds of registered hallmark elements. If in doubt, you can contact the International Association of Assay Offices for more information.

When purchasing one of our pieces you will find on the jewellery our makers mark, the date letter, the metal fineness such as 375 for 9ct gold, 750 for 18ct gold or 950 for platinum.  We also get all of our pieces hallmarked at the London Assay office so you will see their assay office logo of a leopards head, lastly as mentioned above you will find a date letter of the year the piece was made in.

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