UK Hallmarking Explained: What the Marks on Your Ring Mean
TL;DR: UK hallmarking is a legal requirement for gold, silver, platinum, and palladium items above a minimum weight, applied by an independent Assay Office. The marks confirm metal purity, the assay office, and the year of testing — genuine third-party verification, not a maker's own claim.
Why Hallmarking Exists
UK hallmarking has existed in some form since 1300, making it one of the oldest consumer protection systems in the world. Its purpose is straightforward: an independent body, not the seller, verifies that a precious metal item genuinely is what it's sold as. Selling an item above the legal weight threshold as gold, silver, platinum, or palladium without a genuine hallmark is illegal in the UK.
What the Marks Actually Show
Sponsor's mark — identifies the company or individual that submitted the item for hallmarking.
Metal fineness mark — states the purity, such as 750 for 18ct gold (75% pure) or 950 for platinum.
Assay office mark — identifies which of the UK's Assay Offices (London, Birmingham, Sheffield, or Edinburgh) tested the piece.
Date letter — an optional but common mark indicating the year of hallmarking, using a letter code that cycles through a defined sequence.
Which Items Require Hallmarking
Gold items over 1 gram, silver items over 7.78 grams, platinum items over 0.5 grams, and palladium items over 1 gram must be hallmarked by law if sold as that metal in the UK. Very lightweight pieces below these thresholds are exempt, though reputable jewellers typically hallmark regardless where practical.
Why This Matters When Buying
A hallmark is independent verification you can check yourself, rather than relying solely on a seller's description. It also matters for insurance and resale, since it provides objective, third-party evidence of what the piece actually is.
Hallmarking at À Vie Diamonds
Every eligible piece we produce is hallmarked at a UK Assay Office before delivery. Get in touch with any questions about a specific commission.
Frequently Asked Questions
Is hallmarking a legal requirement in the UK? Yes, for gold, silver, platinum, and palladium items above specific minimum weights.
What does the number on a hallmark mean? It states the metal's purity — 750 for 18ct gold, 950 for platinum, for example — as a parts-per-thousand fineness figure.
Which UK cities have Assay Offices? London, Birmingham, Sheffield, and Edinburgh are the UK's four Assay Offices.
Last reviewed: July 2026 · À Vie Diamonds