Hallmarking Act — Selling Precious Metals

What is hallmarking?

A hallmark is an official mark struck on precious metal articles by an independent Assay Office after testing (assaying) the metal to confirm its purity. There are four Assay Offices in the UK: London, Birmingham, Sheffield, and Edinburgh. Each has its own town mark.

A hallmark typically consists of:

• The sponsor's (maker's) mark — your registered mark as the maker or seller.
• The fineness (purity) mark — e.g. 925 for sterling silver, 750 for 18ct gold.
• The Assay Office mark — identifying which office tested the article.
• An optional date letter.

Exemption weights

Not every precious metal item needs a hallmark. The Act provides exemption weights below which hallmarking is not required:

• Gold: under 1 gram
• Silver: under 7.78 grams
• Platinum: under 0.5 grams
• Palladium: under 1 gram

If your item is at or above these weights, it must be hallmarked before you can describe or sell it as gold, silver, platinum, or palladium. Note that the weight refers to the precious metal content, not the total weight of the article including stones or non-metal components.

The Dealer's Notice — you need one at every event

If you sell any items described as gold, silver, platinum, or palladium — even if every piece you make falls below the hallmarking weight threshold — you are legally required to display a Dealer's Notice at your stall.

This catches a lot of jewellery makers off guard. The Dealer's Notice is a specific document approved by the British Hallmarking Council that explains the approved hallmarks to consumers. Under Section 11 of the Hallmarking Act 1973, every person dealing in precious metals must display it in a conspicuous position wherever they sell. That includes craft fairs, market stalls, and pop-up events — not just permanent shops. It also applies to online sales: if you sell precious metal jewellery through a website or Etsy, the notice (or its online equivalent, Dealer's Notice B) must be displayed there too.

The good news: it's free. You can download it from any of the four UK Assay Office websites — London, Birmingham, Sheffield, or Edinburgh. If you print it for use at your stall, it must meet specific size requirements (check the Assay Office website for the current specifications). Laminating it is a good idea if you're selling outdoors.

Failure to display the Dealer's Notice is a separate offence from selling unhallmarked items — you can be fined up to £5,000. Trading Standards officers do check for this at events, and it's one of the simplest things to get right. Download it, print it, put it where customers can see it.

Mixed metals — why base metal affects your hallmarking threshold

The weight exemptions mentioned above — 1g for gold, 7.78g for silver, 0.5g for platinum, 1g for palladium — are straightforward when your piece is made entirely of one precious metal. But if your jewellery combines precious metal with base metal (copper, brass, steel, aluminium), the rules work differently from what most people assume.

For mixed precious and base metal articles, the exemption weight is based on the total weight of all metal in the piece — not just the precious metal. Stones, gems, beads, and non-metal components like cord or resin are excluded from the calculation, but all metal counts.

This means a piece that contains only a small amount of precious metal can still require hallmarking if the base metal pushes the total weight over the threshold.

A practical example: you make a pendant with 7g of copper and 1g of sterling silver. The silver alone is well below the 7.78g threshold. But the total metal weight is 8g — which is above the silver threshold. That piece needs to be hallmarked before you can legally describe it as containing silver and offer it for sale.

This trips up a lot of makers who work with mixed metals, particularly those combining silver with copper, brass, or steel. If you're making mixed-metal pieces, weigh the total metal content (excluding any stones or non-metal elements) and check it against the threshold for whichever precious metal you're using.

If you're unsure whether a piece needs hallmarking, the safest approach is to contact your nearest Assay Office — they're genuinely helpful and will advise you. It's far better to check before selling than to discover the issue when Trading Standards visits your stall.

How to get items hallmarked

You need to:

• 1. Register a sponsor's mark with one of the four UK Assay Offices. This is a unique mark that identifies you as the maker/seller. Registration involves a one-off fee.
• 2. Send your items to an Assay Office for testing. Turnaround times vary but are typically a few days to a couple of weeks.
• 3. The Assay Office tests the metal purity. If it meets the standard, they strike the hallmark. If it does not, the item is returned unmarked (or destroyed, depending on the arrangement).

Costs are modest — typically a few pounds per item for small batches. Many jewellers batch their items and send them periodically.

What counts as a description?

The offence is not just about labelling. You commit an offence if you describe an un-hallmarked article as being a precious metal by any means — including:

• Verbal description ('this is a silver ring').
• Written description on a price tag, business card, or website.
• Implying precious metal content through use of terms like 'sterling', '9ct', '18ct', '925', etc.

If a customer asks 'is this silver?' and it is un-hallmarked silver above the exemption weight, you cannot truthfully say yes without breaking the law. The safest approach is to get everything hallmarked.

Enforcement at craft fairs

Trading Standards officers and Assay Office enforcement teams do visit craft fairs. They may:

• Ask to see hallmarks on items described as precious metals.
• Purchase items for testing (test purchases).
• Check your signage and descriptions for compliance.

Penalties for offences under the Hallmarking Act can include fines and, in serious cases, imprisonment. More commonly, a first offence will result in advice and a warning, but repeat non-compliance is taken seriously.