If you have a gold chain in a drawer, an inherited ring, or a watch you have not worn in years, the small stamps inside it tell a story most people cannot read. Those marks are the hallmark, and once you know how to read them, you can tell what your gold actually is, what it is worth, and how seriously it has been tested. In Ireland we have one of the oldest hallmarking systems in the world. Here is what the stamps mean and how to find them.
What a hallmark actually is
A hallmark is an official set of tiny stamps applied to a piece of precious metal after it has been independently tested. The point is consumer protection. Anyone can claim a ring is 18 karat gold, but an Irish hallmark says that the Assay Office has tested it and confirmed it. Without the hallmark, the only thing standing between you and a misrepresented piece is the word of the seller. We cover the full background in our piece on jewellery hallmarking, and the office itself in our article on the Irish Assay Office.
The stamps you should see
An Irish hallmark is made up of several small marks, stamped close together on the inside of a ring or on a discreet section of a chain. There is the sponsor's mark, identifying the maker. There is the standard mark, a number showing the purity. There is the assay office mark, a harp for Dublin. And there is the date letter, which tells you the year the piece was hallmarked. Some pieces also carry a fineness mark in a different shape, such as a crown for gold. Once you have seen one full hallmark up close, you start to recognise them quickly.
Karat marks: 9, 14, 18, 22 and 24
This is the part most people care about. The number in the hallmark tells you the purity of the gold. 24 karat is pure gold and is rarely used in jewellery because it is too soft. 22 karat is common in some traditions but unusual for everyday wear in Ireland. 18 karat is 75 per cent pure gold and is the standard for fine jewellery. 14 karat is more common in the United States. 9 karat is the most common in Ireland and is 37.5 per cent pure gold. The number can also appear as a fineness figure: 750 for 18 karat, 375 for 9 karat, and so on. The higher the number, the more pure gold in the piece.
How to read a hallmark on your own gold
Take the piece into good light, ideally with a magnifying glass or a phone camera in macro mode. On a ring, look inside the band. On a chain, look at the clasp or the small tag near the clasp. On a pendant, check the back or the bail. The stamps can be small and slightly worn on older pieces, but they are almost always there if the item was sold legally as gold in Ireland or the UK. If you cannot find any mark at all, that tells you something on its own.
What a missing or odd-looking hallmark might mean
No hallmark is not automatic proof that the piece is not gold. Some older items, especially ones that fall below a minimum weight, were not required to be hallmarked. But a missing hallmark on a chunky chain that has clearly been sold as gold should raise questions. So should a hallmark that looks rough, shallow or oddly placed. There is also a category of pieces called bonded gold, which has a thin gold layer over a base metal core. We cover the danger in our article on bonded gold jewellery. An XRF testing machine, explained in how XRF machines spot fake jewellery, can tell the difference in seconds.
Hallmarking and what your gold is worth
The hallmark sets the purity, and the purity sets the price. A 9 karat chain weighing the same as an 18 karat chain is worth less. Add in the live market price of gold, which moves daily, and you have your figure. Our guide to gold prices in Ireland explains how the daily rate works, and our piece on what happens to your gold after you sell it walks through the rest of the process.
Bring it in and we will read it for you
If you are not sure what the stamps mean on your own gold, bring it into our workshop on 5 Mary Street. We will read the hallmark with you, test the gold, and tell you exactly what you have. If you want to take the next step and sell your item, our cash for gold service is built around the same testing process. You should never have to guess what your gold is.