How to read a UK hallmark

What a hallmark actually is

A hallmark is not a maker's decoration. It is a legal guarantee, punched into the metal by an independent assay office after the piece has been tested. It has been required in Britain since 1300, which makes it one of the oldest forms of consumer protection anywhere.

That is why it is worth learning to read. A hallmark is the one mark on a piece of jewellery that somebody else has already verified for you.

Where to look

On a ring, inside the band. On a chain or a bracelet, on the clasp or on a small flat tag beside it. On a brooch, on the back near the pin. On a pocket watch, inside the case back (you may need to open it).

The marks are small, and on a piece that has been worn for fifty years they may be worn nearly flat. Don't polish them to bring them up. Polishing removes metal, and a worn hallmark that can still be read under a loupe is worth more than a bright one that has been rubbed away.

The three marks that are always there

Since 1999 a British hallmark has had to carry three marks. Everything else is optional.

1. The sponsor's mark. Two or more letters in a shaped surround, usually the initials of the maker or the firm that submitted the piece. It tells you who put it in, not necessarily who made it.

2. The fineness mark. A number in an oval or a shield that says how much pure metal is in the alloy, in parts per thousand. This is the one that matters most for value:

3. The assay office mark. A small picture showing which office tested it. Four offices still operate in the United Kingdom:

If your piece carries something else (a wheatsheaf, a three-towered castle, a shield with three sheaves and a sword), it is likely from an office that has since closed, which means the piece is older than 1964. Chester closed in 1962 and Glasgow in 1964; Exeter and Newcastle closed long before that. An office mark that no longer exists is a useful dating clue in itself.

The date letter

This is the one people enjoy. A single letter, in a shaped shield, showing the year the piece was assayed. The letter changes each year and the alphabet restarts with a different typeface and a different shield shape, so the combination of letter, font and shield gives an exact year.

The catch: the cycles are different for each office, so a date letter only means something once you know which office punched it. There is no single chart that works for everything. The assay offices publish their own, and that is where to look it up.

Since 1999 the date letter has been optional. Most pieces still carry one, but a modern piece without one is not suspect.

What you will not find, and why that is normal

Plenty of real gold and silver carries no hallmark at all. The usual reasons:

It is too light to need one. Below certain weights a piece is legally exempt: gold under one gram, silver under 7.78 grams, platinum under half a gram. A fine chain or a small pair of earrings may well be under the limit.

It is foreign. Many countries mark differently or barely at all. American gold is commonly stamped "14K" with no office mark. That is not a British hallmark, but it is not a forgery either.

It has worn away, or the marked part (a clasp, a fitting) was replaced at some point.

It is not what you hoped. Some pieces are unmarked because there was nothing to mark. But this is the last explanation to reach for, not the first.

Words that are not hallmarks

"9ct" or "18ct" alone is a description, not a hallmark. It may be perfectly accurate; it has just not been independently tested.

"Rolled gold", "gold filled", "RG", "GF" mean a layer of real gold bonded to a base metal. Real gold, very little of it.

"EPNS" stands for electro-plated nickel silver. It is silver plate. The plate is worth almost nothing; the object sometimes is not.

"925" with no other marks usually means sterling silver made abroad. It is a fineness mark without a hallmark around it.