Hallmarks were introduced 700 years ago according to the British Hall Marking Council as a way of preventing fraud and proving the metal has been identified and tested to ensure the legal standards of purity (fineness) have been met.
There are many hallmarks that are stamped on precious metals however three are compulsory. Purity mark (ie the precious metal content), the jewellery maker’s own mark, the Assay office where the item was tested.
All small items less than (in grams) 0.5 for platinum, 1 for gold, 7.78 for silver and 1 for palladium do not need to be hallmarked.
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