What does 925K on earring mean?

The "925K" marking on an earring indicates that the earring is made of sterling silver. The "925" part refers to the purity of the silver, which is 92.5% pure silver and 7.5% other metals, usually copper. The "K" stands for karat, which is a unit of measurement for the purity of gold. However, in this case, the "K" is used incorrectly since karat is not the correct unit of measurement for silver purity. The correct marking for sterling silver should be "925" or "Sterling."