PURIX
AI characterWhat does karat measure?
Karat tells you, out of 24, how much of a gold alloy is pure gold. Imagine dividing the alloy into 24 equal parts: the karat is how many of those parts are gold. In 24 karat, all of the parts are gold; that is why 24 karat means pure gold.1
As the karat goes down, the share of gold falls and the share of other metals rises. For example, three quarters of 18 karat gold is gold; the remaining quarter is other metals, mostly copper or silver.1
Karats and gold content
| Karat | Gold parts out of 24 | Gold content | Fineness |
|---|---|---|---|
| 24 karat | 24 | Pure gold | 999 and above |
| 22 karat | 22 | 91.6% | 916 |
| 18 karat | 18 | 75% | 750 |
| 14 karat | 14 | 58.5% | 585 |
How do you convert karat to fineness?
Fineness writes the same ratio out of 1,000. Divide the karat by 24 and multiply by 1,000 to get the fineness: 18 ÷ 24 × 1,000 = 750. That is why an 18 karat piece is stamped 750 and a 14 karat piece is stamped 585.
Can you tell karat by eye?
No. Colour, shine or weight alone do not show the karat; karat is determined by measurement. Three methods are common at jewellers: the touchstone, the acid test and XRF analysis.
FAQ
Is 24 karat gold pure?
Yes. 24 karat shows that all 24 of the alloy's 24 parts are gold; as fineness it is written 999 and above.
What does 18 karat mean?
It means 18 of the 24 parts are gold, which is 75%. Its fineness is 750.
What is the fineness of 14 karat?
585. In other words, 585 of every thousand parts are gold.
Are karat and fineness the same thing?
They are two ways of writing the same ratio: karat is out of 24, fineness is out of 1,000.
Karat isn’t guessed. It’s measured.
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