Gold Karats Explained: Purity, Fineness and Hallmarks

What does gold karat mean?

Karat measures how many of 24 total parts are gold. Pure or nearly pure gold is described as 24K. An 18K alloy contains 18 parts gold and six parts other metals, while a 14K alloy contains 14 parts gold and ten parts other metals.

Mixing gold with silver, copper, zinc or other metals can improve durability and change colour. A lower karat does not automatically mean a badly made item. It means a smaller proportion of the item's metal is gold.

Gold karat and hallmark chart

Fineness expresses purity in parts per thousand. A 750 mark therefore means that 750 of every 1,000 parts are gold. Small rounding differences explain why 14K may appear as 583 or 585 and 22K may appear as 916 or 917.

Standards and marking practices differ by jurisdiction. The chart is a conversion reference, not proof that a particular item is genuine.

How to read common gold markings

585 and 14K describe almost the same purity

Both indicate approximately 58.5% gold. One uses fineness and the other uses the 24-part karat system. The mark may be found near a clasp, inside a ring or on the back of a pendant.

A maker's mark and an assay mark serve different purposes

A maker or sponsor mark identifies the party responsible for the item. An official hallmarking system may also identify the assay office and fineness standard. The exact combination depends on where the item was made and sold.

GP, HGE, RGP and GF change the meaning

These abbreviations can indicate gold plate, heavy gold electroplate, rolled gold plate or gold filled material. The surface may be gold while most of the item's weight is a different metal. Do not apply the visible karat number to the entire item without understanding the full mark.

How purity affects melt value

Melt value is based on fine-gold content, not total weight alone. Ten grams of 18K gold contains approximately 7.5 grams of fine gold. Ten grams of 14K contains approximately 5.833 grams.

Enter the verified weight and karat into the scrap gold calculator to apply the current live gold reference.

Solid gold, gold filled and gold plated are not equivalent

Karat gold is an alloy throughout the relevant gold part. Gold-filled and rolled-gold products use a mechanically bonded layer over another metal. Gold-plated products use a much thinner surface layer. A plated item's gross weight cannot be valued as though the complete object were solid karat gold.

How to verify gold before valuing it

1. Photograph and record every visible mark.
2. Weigh the item on a calibrated scale without damaging it.
3. Check whether stones, springs or non-gold components affect the weight.
4. Use non-destructive professional testing for valuable or uncertain items.
5. Request the testing method and net gold weight in writing before selling.

Home magnet and visual checks can reveal obvious inconsistencies, but they do not establish exact purity. Acid testing can damage an item and should be performed by someone who understands the method.