In the UK hallmarking has a long and distinguished history, dating back several hundred years. Below is a copy of  the Dealers notice for your information, which explains the different  hallmarks and their use. By law all British jewellers if trading in precious metals should be registered at one of the Assay offices in the UK. This means that if it's hallmarked you are guaranteed  that your buying genuine, silver, gold, platinum or pallidium that has been certified as to it's fineness.

It's worth noting for example, that the 925 stamp or the words sterling silver are often used by jewellers trading outside of the UK, and that items marked as such or without a genuine hallmark cannot be guaranteed in the UK, as to the metals fineness...

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