Usually, when buying fine jewellery made of metals such as silver or gold, we want to be sure that the jewellery we are looking at is genuine - made of the stated material whether it is 18ct gold or Sterling Silver. But it's not always easy to tell whether a jewellery piece is what it is supposed to be and manufacturers' marks may not always be accurate.
A hallmark is a good way to know whether the metal in the jewellery is genuinely of the standard claimed by the seller.
Currently, hallmarking can be applied to platinum, palladium, gold, and silver articles. Any item that is made of those metals must be hallmarked by an Assay office, who test the article of concern and if it meets the required standards apply the hallmark. Hallmarks are traditionally applied by a punch but you can find an increasing number of laser engraved hallmarks.
Minimum weights
Here are the minimum weights, over which all fine metal articles must be hallmarked.
- Platinum - 0.5g
- Palladium - 1.0g
- Gold - 1.0g
- Silver - 7.78g
Any jewellery below this weight is exempt from hallmarking - it does not need to have a hallmark in order for it to be sold legally.
Depending on the metal, the standard is different. Gold is measured in carats, unlike the other three metals. Some of the most popular standards include 18ct Gold - which means that the item must have a gold content of at least 75% by weight; Sterling Silver (also called 925 Silver) must have a minimum 92.5% silver content by weight.
Of course, there are more standards. For example, gold can be 9ct and can go up to 24ct which corresponds to pure gold. While Sterling Silver is not the only standard, it's the most widely used and known one in the jewellery industry.
How can you read a hallmark?
Hallmarks generally consist of three marks:
- The Sponsor's Mark - this tells you who manufactures or sponsors the mark
- The Fineness Mark - this shows the quality of the metal - for example, 925 Silver means 92.5% Silver and 7.5% other metals.
- The Assay Office Mark - this mark shows which Assay Office was the one to test and hallmark the item.
They are the required minimum - every hallmark should show these. Additionally, it is possible to include more information through another three marks of:
- Traditional Fineness Symbols - this used to be the traditional way of showing the quality of the metal, but has now been replaced by the fineness mark described above.
- Date Letter - A single letter, showing which year the item was hallmarked in. For example, "S" would be used in hallmarks made throughout 2017, while in 2018 "T" will be used. The final letter will be used in 2024, as the order is alphabetical.
- International Convention Marks - when applied to a piece, these marks allow it to be sold in other countries which are part of the Hallmarking Convention.
Which countries are part of the Hallmarking Convention?
Currently, 19 countries are members of the convention: Austria, Cyprus, Czech Republic, Denmark, Finland, Hungary, Ireland, Israel, Latvia, Lithuania, Netherlands, Norway, Poland, Portugal, Slovak Republic, Slovenia, Sweden, Switzerland, United Kingdom.
Note that some countries, like France, Italy, or Spain accept some UK assay office hallmarks even if they are not part of the Convention themselves. Also, Germany and Belgium do not currently have any hallmark requirement.
In the UK it is illegal to sell or describe any item as Silver, Gold, Palladium or Platinum unless it is hallmarked or below the relevant exemption weight!
