Carat of gems and karats of gold: not the same thing
In Spanish “quilate” is used for two different measures: the weight of a gem and the purity of gold. In English they are distinguished: carat and karat.
Carat of gems #
A unit of weight: 1 carat = 0.2 grams. It is divided into 100 points. A 0.5 carat diamond weighs 0.1 grams.
Karats of gold #
They indicate how many parts out of 24 are gold: 24K gold is almost pure; 18K has 18 parts gold (75%); 14K, 14 parts (58.5%); 9K, 9 parts (37.5%). See 14 or 18 karat.
Chart #
| Gold | Purity | Mark |
|---|---|---|
| 24K | 99.9% | 999 |
| 22K | 91.6% | 916 |
| 18K | 75% | 750 |
| 14K | 58.5% | 585 |
| 9K | 37.5% | 375 |
Fineness #
Hallmarks state fineness in parts per thousand (hallmarks and stamps); it is the same as karats, expressed differently.
See also #
This entry was drafted with the help of AI and is pending review by the author.
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