Karat is a unit of measurement for the purity of gold alloys. It is often used to refer to the percentage of gold in a jewelry item. Pure gold is 24Karat, meaning that it contains 24 parts of gold and is 100% pure. Lower Karat numbers indicate a lower purity, with 18Karat gold containing 18 parts of gold and 6 parts of other metals. Karat is usually abbreviated as K or Kt.
