what is a hallmark?
Hallmarks are a key part of determining the purity of items being advertised and sold as containing precious metals, silver, gold, platinum, and palladium. In the UK, it is illegal to sell jewellery or items over certain weight without providing a hallmark.
Both silver and gold are soft when in their purest form and would be unsuitable for many items. Jewellery especially would become easily scratched and misshapen if made from pure silver or gold.
Pure silver will also tarnish over time, reacting to sulphur in the air. Because of this, silver and gold are usually mixed with a small amount of other metals to form a more useful alloy; one that is more durable, adds strength, and less likely to tarnish. For example, 925 sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. Fine silver is 99.9% pure silver, it is a very soft metal and is often used to make the setting to secure flat domed stones because of its malleability.
Why do we use hallmarks?
In an ideal world, we could trust each manufacturer’s word regarding what amount of what metal was contained in an item. However, sadly, unscrupulous jewellers, metalsmiths and criminals have attempted to create fakes, or fraudulently claim higher metal content than used to make more money.
Hallmarks are applied by independent officials, known as assayers, who guarantee the metal content of an item on behalf of a country’s government. They are legal stamps, that prove the metal has been tested and is of the quality stated.
If a precious metal item weighs less than a certain amount it is not compulsory to apply a hallmark. The minimum weight thresholds are:
• gold 1 gram
• silver 7.78 grams
• platinum 0.5 gram
• palladium 1 gram
Many makers will also hallmark items below the requirement to demonstrate the quality.
A complete hallmark consists of 3 compulsory marks. If an item has not been stamped or marked with these 3 markings then it has not been properly hallmarked. All 3 marks must be present.
1. A sponsor’s or maker’s mark
This is the registered mark of the company or person that sends the item for hallmarking. Manufacturers, wholesalers, retailers, importers and more can all be sponsors. In the UK, this mark has at least 2 letters, and all marks are unique.
2. A metal and purity (fineness) mark
This mark shows the precious metal content in the item, recorded in parts per thousand. This means that the number tells you the proportion of precious metal content in the alloy. For example, the fineness mark of 9 carat gold is 375. This tells us that the alloy must have at least 375 parts gold per 1,000. The shape surrounding the number indicates the metal type, which you can see in the diagram below.
3. An Assay Office mark
This mark shows which of the 4 Assay Office in the UK tested and hallmarked the item. A full UK hallmark:
A full UK hallmark tells you:
1. Who submitted the article for hallmarking (sponsor’s mark)
2. What the final metal is made of (Metal fineness mark)
3. Where the article was hallmarked (Assay office town mark)
4. When the article was hallmarked (date letter) is optional
There are several additional marks which can be added but these are not a legal requirement.
A 925 stamp on its own in a ring does not denote that the item it sterling silver, these stamps can easily be bought on the internet for a few pounds.
And because of the increasingly high-value nature of gold, it is perhaps unsurprising that unscrupulous people attempt to produce fake gold items. One of the simplest ways to try and convince someone a fraudulent item is made of real gold, is to stamp it with fake hallmarks. Make sure you purchase your precious items from a reputed maker who is registered with a UK Assay Office – registration should be displayed on their store whether physical or online.
If you are sold an item of jewellery made with gold, silver, platinum or palladium over the minimum weight and it is not hallmarked, then not only is the quality not guaranteed, and the seller is breaking the law. This is regardless of whether the sale is in a shop or online.