What is the meaning of 14tk for stud earring?

The "14tk" marking on a stud earring means that it is made of 14-karat gold. Karat is a unit of measurement used to indicate the purity of gold, with 24-karat being pure gold. So, 14-karat gold means that the earring is made of gold that is 14/24, or approximately 58.3%, pure.