What does the marking 188 cn means On my earrings?

The marking "188 CN" on your earrings likely indicates the metal composition and origin of the jewelry. The "188" may refer to the purity of the metal, suggesting it is made from a type of metal alloy, while "CN" typically stands for "China," indicating the country of manufacture. This kind of marking is common in jewelry to denote both quality and origin. If you're looking for more specific information, consulting a jeweler could provide additional insights.