The hallmarks on jewellery are the symbols which are engraved to represent who made it, it’s guaranteed standard of fineness, the Assay Office at which it was tested and marked and the year in which it was tested and marked.

A Sponsors Mark is the unique mark of the company or person who is responsible for sending the item for hallmarking.

A Standard Mark illustrates the fineness and purity of the metal used. In the UK we measure the purity of the previous metal content in parts per 1000, for example 375 parts per 1000 by weight would equal 9 carat gold standard.

375 parts/1000 = 9 carat gold (37.5% pure gold)
585 parts/1000 = 14 carat gold (58.5% pure gold)
750 parts/1000 = 18 carat gold (75% pure gold)
916 parts/1000 = 22 carat gold (91.6% pure gold)
999 parts/1000 = 24 carat gold (99% pure gold)


9 carat

This is the most affordable and common type of gold on the market, it has a light yellow tone to it. This means that it is stronger than other carats as it is mixed with other metals.

14 carat

This has a higher percentage of pure gold and has a warm yellow tone.

18 carat

This has a bright yellow tone but can have white metals added to produce a white gold or produce rose gold by adding copper to it.

22 carat

This is an even brighter yellow and is fairly soft so is not the best for stone set jewellery but works well for plain jewellery.

24 carat

This is the highest carat available which makes it highly valuable and therefore more expensive. It has a natural yellow tone and has a soft composition. It is not commonly used for jewellery so instead it is usually used for gold coins.

The Assay Office marks

Gold carats explained