Every figure in a gold valuation starts from one question: how much of this piece is actually gold? Three systems answer it, and they all say the same thing in different languages.
Carat: parts of twenty-four
Carat describes gold content as a fraction of 24. Pure gold is 24 carat. A 22ct piece is 22 parts gold in 24; 18ct is 18 parts; 9ct is 9 parts — a little over a third gold. Everything that is not gold is alloy, usually copper, silver or zinc, added for hardness and colour. The alloy carries no precious-metal value, which is why a heavy 9ct chain can be worth less than a much lighter 22ct one.
Fineness: parts of a thousand
Modern marks usually state purity in parts per thousand instead. The common figures map directly onto the carat scale:
- 916 — 22 carat
- 750 — 18 carat
- 585 — 14 carat
- 375 — 9 carat
A ring stamped 750 and a ring described as 18ct are making exactly the same claim.
Hallmarks: the claim, witnessed
A hallmark is a set of marks struck into the metal recording its fineness — and often who submitted it and where it was tested. Look inside a ring band, on a clasp, or on the reverse of a pendant.
Plenty of genuine gold carries no hallmark at all. The mark may have worn away, the piece may predate marking requirements, or it may have been made somewhere marking is not customary. An unmarked piece is not a problem and not a red flag: it simply means fineness has to be established by examination rather than read off the metal. That is part of what a proper counter assessment is for.
Why the stamp is checked rather than trusted
A mark is a claim, and claims are tested. Worn marks misread, plated items imitate solid ones, and the occasional stamp is simply wrong. A careful buyer reads the mark under magnification and then verifies it against the metal itself — which is why the weight and fineness you are shown at the counter are measured, never assumed.