Hallmarking - The Facts


So...what is it and why is it important?.....

Hallmarking in the United Kingdom has a long history dating back 700 years. It is, quite simply, the independent testing and marking of gold, silver, platinum and palladium and guarantees conformity to all legal standards of purity. As such, it represents the oldest form of consumer protection in the United Kingdom. 

The companies or bodies that carry out the necessary tests and checks on the purity of the different metals are called Assay Offices.

There are currently four UK Assay Offices: Birmingham, London, Sheffield and Edinburgh. 

The word "hallmark" originally meant "marked at Goldsmiths' Hall" when the Goldsmiths' Company was the sole authority entrusted with this statutory requirement. A hallmark indicates Who, What, Where, When and is either stamped or laser engraved inside in this case the band of the ring: 

Hallmarking compulsory marks

Even the most experienced jeweller can not tell how much precious metal is in an alloy. So, they may well be able to guess that a metal is white gold, but they will not be able to confirm the percentage of gold within the metal. So, it is a requirement to have jewellery and giftware independently tested and hallmarked to confirm they meet the legal standard in this country. This helps prevent fraud, as sadly the price of precious metal could cause a temptation to cheat people, by selling them items that are not what they claim to be.

The term carat when it refers to gold, actually refers to the percentage of purity in the metal. 24 carat is 100% pure gold. 18 carat gold is therefore 75% pure gold mixed with 25% alloy and 9 carat gold is 37.5% pure gold. This then makes sense when you know that the mark for 18ct gold is 750 (75%), the mark for 14 carat gold is 585 (58.5%) and the mark for 9 carat gold is 375 (37.5%).

There are a exemptions from the hallmarking laws and these are when an item is under the legal weight threshold as follows:

  • 0.5g Platinum
  • 1g Gold
  • 1g Palladium
  • 7.78g Silver

To find out more, go to https://theassayoffice.co.uk/ where the Birmingham Assay Office explains the hallmarking process in detail.