Karat
Definition
Karat is a measure of gold purity on a 24-part scale, where 24 karat is pure gold. Lower numbers show how many parts out of 24 are gold, so 18-karat is 75 percent and 14-karat is 58.5 percent.
Karat is the traditional jewelry-and-coin scale for stating how much of an item is actually gold.
Why it matters
The karat stamp tells you the gold content, which drives both value and durability. Pure 24-karat gold is soft and dents easily, so jewelry is often 14- or 18-karat for strength. When you sell scrap or jewelry, the buyer pays for the gold fraction, so a 14-karat piece is worth far less per gram than a 24-karat one of the same weight.
In practice
To estimate melt value, multiply the item’s weight by its karat fraction, then by the gold price per unit. A 10-gram 14-karat ring contains about 5.85 grams of gold. A melt-value calculator handles this math once you enter weight and karat.
Common confusion
Karat (purity) is not carat (gem weight). They sound alike but measure different things. Karat is also just another way of stating fineness; 24-karat corresponds to roughly .999.