Carat (ct.) is a metric unit of mass for the weighing of precious metals, precious stone and gems (e.g. diamond, ruby, sapphire).
Carat (ct, Kt) corresponds to the mass fraction of gold in precious alloys used in jewellery.
1 ct = 0.4167 %
24 ct = 100 %
24 carat gold is pure gold, 18 carat is 75 % gold and 25 % of some other metal such as silver or copper.
Generalic, Eni. "Carat." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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